diff --git a/.gitignore b/.gitignore
index c5b83a3..be0fcd2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,8 @@
 __pycache__/
 /.vscode/
 /apps/hd_generated.cu8
+CMakeLists.txt.bak*
+.claude/
+.history/
+/examples/*
+!/examples/README
diff --git a/CMakeLists.txt b/CMakeLists.txt
index ff4b884..d598090 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -158,15 +158,16 @@ else()
     include (ExternalProject)
 
     set (FDK_AAC_PREFIX "${CMAKE_BINARY_DIR}/fdk-aac-prefix")
+
     ExternalProject_Add (
         fdk_aac_external
-        GIT_REPOSITORY "https://github.com/argilo/fdk-aac.git"
-        GIT_TAG 3b63dab59416a629f3de82463eb3875319a086d5
+        GIT_REPOSITORY "https://github.com/secludedhusky/fdk-aac.git"
+        GIT_TAG edits-parametric
         PREFIX ${FDK_AAC_PREFIX}
 
         BINARY_DIR ${FDK_AAC_PREFIX}/src/fdk_aac_external
         UPDATE_COMMAND ""
-        CONFIGURE_COMMAND ./autogen.sh && ./configure --prefix=${FDK_AAC_PREFIX} --disable-shared --enable-static CXXFLAGS=-fPIC
+        CONFIGURE_COMMAND chmod +x autogen.sh && ./autogen.sh && ./configure --prefix=${FDK_AAC_PREFIX} --disable-shared --enable-static CXXFLAGS=-fPIC
         BUILD_COMMAND make
     )
 
diff --git a/README.md b/README.md
index 5de69e5..da48377 100644
--- a/README.md
+++ b/README.md
@@ -30,17 +30,45 @@ This block encodes audio into High-Definition Coding (HDC) frames. The input sam
 
 ### PSD encoder
 
-This block encodes Program Service Data PDUs, as described in https://www.nrscstandards.org/standards-and-guidelines/documents/standards/nrsc-5-d/reference-docs/1028s.pdf. PSD conveys information (e.g. track title & artist) about the audio that is currently playing.
+This block encodes Program Service Data PDUs, as described in https://www.nrscstandards.org/standards-and-guidelines/documents/standards/nrsc-5-d/reference-docs/1028s.pdf. PSD conveys information (e.g. track title & artist) about the audio that is currently playing. The encoder supports all ID3 frames defined in NRSC-5 Table 5-1.
 
 To control latency, connect the "clock" output of the Layer 1 encoder to the "clock" input of the PSD encoder, and set "Bytes/frame limit" to 128 (if the L2 frame size is 24000 or larger) or 64 (if the L2 frame size is smaller than 24000).
 
-To dynamically update title, artist, and XHDR data, connect a Socket PDU (TCP Server) block to the "set_meta" input, and send any of the following commands via TCP, followed by a carriage return:
+To dynamically update metadata, connect a Socket PDU (TCP Server) block to the "set_meta" input, and send any of the following commands via TCP, followed by a carriage return:
 
-* `titleExample Title` — set title to `Example Title`
-* `artistExample Artist` — set artist to `Example Artist`
+**Basic Metadata (PSD Types 1-4):**
+* `titleExample Title` — set title to `Example Title` (TIT2)
+* `artistExample Artist` — set artist to `Example Artist` (TPE1)
+* `albumExample Album` — set album to `Example Album` (TALB)
+* `genreRock` — set genre to `Rock` (TCON)
+
+**Comment (PSD Type 5 - COMM):**
+* `commentRecorded live at Madison Square Garden` — set comment text
+* `comment_shortInfo` — set comment short description
+* `comment_languageeng` — set comment language (3-byte ISO 639-2 code, default: eng)
+
+**Commercial Frame (PSD Type 6 - COMR):**
+* `commercial_price$9.99` — set price string
+* `commercial_valid20261231` — set expiration date (YYYYMMDD format)
+* `commercial_urlhttps://example.com/buy` — set contact URL for purchase
+* `commercial_received0` — set received-as byte (how merchandise is received)
+* `commercial_sellerExample Store` — set seller name
+* `commercial_descBuy now and save 20%!` — set advertisement description
+
+**Reference Identifier (PSD Type 7 - UFID):**
+* `ufid_ownerhttp://musicbrainz.org` — set owner identifier URL
+* `ufid_idabc123def456` — set unique identifier (up to 64 bytes)
+
+**Album Art (XHDR):**
 * `lot1337` — display album art contained in LOT file 1337
 * `lot-1` — display station logo
 
+**Notes:**
+* All metadata fields are optional except Title and Artist (per NRSC-5 requirements)
+* Maximum PSD message size is 1,018 bytes (excluding 6-byte overhead)
+* Title, Artist, Album, and Genre frames should be limited to less than 128 characters
+* Binary pictures are not supported in PSD; use LOT protocol for album art transmission
+
 ### SIS & SIG encoder
 
 This block encodes Station Information Service PDUs, as described in https://www.nrscstandards.org/standards-and-guidelines/documents/standards/nrsc-5-d/reference-docs/1020s.pdf, and assembles them into the PIDS and SIDS logical channels. SIS provides information about the station.
@@ -89,23 +117,57 @@ The "clock" output of the Layer 1 encoder must be connected to the "clock" input
 
 This block sends files to the receiver (for instance, containing album art or a station logo) by encoding them as Advanced Application Services (AAS) PDUs, according to the Large Object Transfer (LOT) protocol. The "aas" output must be connected to the Layer 2 encoder's "aas" input, and the "ready" output of the Layer 2 encoder must be connected to the "ready" input of the LOT encoder to tell it when it should produce output.
 
+#### File Expiry
+
+Files transmitted via LOT include an expiry date/time. The expiry can be set in the GRC block's "Expiry" parameter (default: "45 minutes") or specified per-file via TCP commands. The expiry parameter supports two formats:
+
+**Relative Time Format** (recommended):
+* `15 milliseconds`, `15ms`, `15mil`
+* `120 seconds`, `120s`, `120sec`
+* `15 minutes`, `15m`, `15min`
+* `2 hours`, `2h`, `2hr`
+* `7 days`, `7d`
+* `2 weeks`, `2w`, `2wk`
+* `6 months`, `6mn`, `6month`
+* `1 year`, `1y`, `1yr`
+
+**ISO 8601 / TZ Format:**
+* `2026-12-31T23:59:59+00:00` (with timezone offset)
+* `2026-12-31T23:59:59Z` (UTC with 'Z' suffix)
+* `2026-12-31 23:59:59+00:00` (space separator also supported)
+
+#### TCP Commands
+
 To allow new files to be sent at runtime, connect a Socket PDU (TCP Server) block to the "file" input. To read a new file from disk, send the following command, followed by a carriage return:
 
 ```
-file|<lot_id>|<filename>
+file|<lot_id>|<filename>|<expiry>
+```
+
+Example:
+```
+file|1337|album_art.png|15 minutes
 ```
 
 To stream in a file over the network connection, send the following command, followed by a carriage return:
 
 ```
-streamfile|<lot_id>|<size>|<filename>
+streamfile|<lot_id>|<size>|<filename>|<expiry>
+```
+
+Example:
+```
+streamfile|1337|4096|album_art.png|2 hours
 ```
 
 Then send the file itself over the same network connection.
 
 The `apps/send_album_art.py` script demonstrates how to stream an album art file and request for it to be displayed by the receiver.
 
-Note: Station logo and album art files must use PNG or JPEG format, and be 200x200 pixels in size.
+**Notes:**
+* The expiry parameter is optional in TCP commands; if omitted, the default expiry from the GRC block is used
+* Station logo and album art files must use PNG or JPEG format, and be 200x200 pixels in size
+* Expiry dates are encoded in the LOT header and transmitted to the receiver
 
 ### Layer 2 encoder
 
diff --git a/apps/hd_tx_hackrf.py b/apps/hd_tx_hackrf.py
old mode 100755
new mode 100644
index c539bb7..82e445c
--- a/apps/hd_tx_hackrf.py
+++ b/apps/hd_tx_hackrf.py
@@ -81,11 +81,45 @@ def __init__(self):
         self.osmosdr_sink_0.set_bb_gain(20, 0)
         self.osmosdr_sink_0.set_antenna('', 0)
         self.osmosdr_sink_0.set_bandwidth(0, 0)
-        self.nrsc5_sis_encoder_0 = nrsc5.sis_encoder(mode=nrsc5.pids_mode.FM, short_name='ABCD-FM', slogan='This is ABCD-FM', message='Generated by GNU Radio', program_names=['HD1'], program_types=[nrsc5.program_type.NEWS], data_types=[], data_mime_types=[], latitude=40.6892, longitude=(-74.0445), altitude=93.0, country_code='US', fcc_facility_id=0)
+        # Data channels: port 0x1010 (LOT ID 1010, Text) and port 0x1011 (LOT ID 1011, Text)
+        # These are advertised in SIG so decoders reassemble LOT on these ports
+        self.nrsc5_sis_encoder_0 = nrsc5.sis_encoder(
+            mode=nrsc5.pids_mode.FM,
+            short_name='ABCD-FM',
+            slogan='This is ABCD-FM',
+            message='Generated by GNU Radio',
+            program_names=['HD1'],
+            program_types=[nrsc5.program_type.NEWS],
+            data_types=[],
+            data_mime_types=[],
+            latitude=40.6892,
+            longitude=(-74.0445),
+            altitude=93.0,
+            country_code='US',
+            fcc_facility_id=0,
+            data_channels=[
+                nrsc5.data_channel_config(0x1010, 1010, int(nrsc5.service_data_type.TEXT), int(nrsc5.mime_hash.TEXT)),
+                nrsc5.data_channel_config(0x1011, 1011, int(nrsc5.service_data_type.TEXT), int(nrsc5.mime_hash.TEXT)),
+            ],
+            exciter_manufacturer_id='CS',
+            importer_manufacturer_id='CS',
+            exciter_core_version=[1, 0, 0, 0],
+            exciter_mfr_version=[1, 0, 0, 0],
+            importer_core_version=[1, 0, 0, 0],
+            importer_mfr_version=[1, 0, 0, 0],
+            importer_configuration_number=0)
         self.nrsc5_psd_encoder_0 = nrsc5.psd_encoder(0, 'Title', 'Artist', 128)
         self.nrsc5_lot_encoder_0_0 = nrsc5.lot_encoder('album_art.jpg', 1337, 0x1000)
         self.nrsc5_lot_encoder_0 = nrsc5.lot_encoder('SLABCD$$010000.png', 42, 0x1001)
+<<<<<<< Updated upstream
         self.nrsc5_l2_encoder_0 = nrsc5.l2_encoder(1, 0, 146176, 2000, nrsc5.blend.ENABLE, ccc_width=24)
+=======
+        # Data-only LOT encoders on ports 0x1010 and 0x1011
+        # These match the data_channels configured above in the SIS encoder
+        self.nrsc5_lot_encoder_dc0 = nrsc5.lot_encoder('STRWRI_Richmond_20260203_034254.txt', 1010, 0x1010)
+        self.nrsc5_lot_encoder_dc1 = nrsc5.lot_encoder('STRWRI_Richmond_20260203_034254.txt', 1011, 0x1011)
+        self.nrsc5_l2_encoder_0 = nrsc5.l2_encoder(1, 0, 146176, 2000, nrsc5.blend.ENABLE)
+>>>>>>> Stashed changes
         self.nrsc5_l1_fm_encoder_mp1_0 = nrsc5.l1_fm_encoder(1)
         self.nrsc5_hdc_encoder_0 = nrsc5.hdc_encoder(2, 64000)
         self.network_socket_pdu_1 = network.socket_pdu('TCP_SERVER', '', '52002', 10000, False)
@@ -132,9 +166,13 @@ def __init__(self):
         self.msg_connect((self.nrsc5_l1_fm_encoder_mp1_0, 'clock'), (self.nrsc5_sis_encoder_0, 'clock'))
         self.msg_connect((self.nrsc5_l2_encoder_0, 'ready'), (self.nrsc5_lot_encoder_0, 'ready'))
         self.msg_connect((self.nrsc5_l2_encoder_0, 'ready'), (self.nrsc5_lot_encoder_0_0, 'ready'))
+        self.msg_connect((self.nrsc5_l2_encoder_0, 'ready'), (self.nrsc5_lot_encoder_dc0, 'ready'))
+        self.msg_connect((self.nrsc5_l2_encoder_0, 'ready'), (self.nrsc5_lot_encoder_dc1, 'ready'))
         self.msg_connect((self.nrsc5_l2_encoder_0, 'ready'), (self.nrsc5_sis_encoder_0, 'ready'))
         self.msg_connect((self.nrsc5_lot_encoder_0, 'aas'), (self.nrsc5_l2_encoder_0, 'aas'))
         self.msg_connect((self.nrsc5_lot_encoder_0_0, 'aas'), (self.nrsc5_l2_encoder_0, 'aas'))
+        self.msg_connect((self.nrsc5_lot_encoder_dc0, 'aas'), (self.nrsc5_l2_encoder_0, 'aas'))
+        self.msg_connect((self.nrsc5_lot_encoder_dc1, 'aas'), (self.nrsc5_l2_encoder_0, 'aas'))
         self.msg_connect((self.nrsc5_sis_encoder_0, 'aas'), (self.nrsc5_l2_encoder_0, 'aas'))
         self.connect((self.analog_wfm_tx_0, 0), (self.rational_resampler_xxx_0_0, 0))
         self.connect((self.blocks_add_xx_0, 0), (self.blocks_multiply_const_vxx_1, 0))
diff --git a/grc/nrsc5_hdc_encoder.block.yml b/grc/nrsc5_hdc_encoder.block.yml
index 520dcbe..79b4b39 100644
--- a/grc/nrsc5_hdc_encoder.block.yml
+++ b/grc/nrsc5_hdc_encoder.block.yml
@@ -13,6 +13,17 @@ parameters:
     label: Bitrate
     dtype: int
     default: 64000
+-   id: use_parametric_stereo
+    label: Stereo Mode
+    dtype: enum
+    default: 'False'
+    options: ['False', 'True']
+    option_labels: ['Regular Stereo (AOT 127)', 'Parametric Stereo (AOT 128)']
+    hide: ${ 'all' if channels == 1 else 'none' }
+-   id: tx_digital_gain
+    label: TX Digital Audio Gain (dB)
+    dtype: int
+    default: 0
 
 inputs:
 -   domain: stream
@@ -25,9 +36,10 @@ outputs:
 asserts:
 - ${ 1 <= channels <= 2 }
 - ${ 0 < bitrate }
+- ${ -8 <= tx_digital_gain <= 6 }
 
 templates:
     imports: import nrsc5
-    make: nrsc5.hdc_encoder(${channels}, ${bitrate})
+    make: nrsc5.hdc_encoder(${channels}, ${bitrate}, ${use_parametric_stereo}, ${tx_digital_gain})
 
 file_format: 1
diff --git a/grc/nrsc5_l2_encoder.block.yml b/grc/nrsc5_l2_encoder.block.yml
index 1ca283f..a6edfe5 100644
--- a/grc/nrsc5_l2_encoder.block.yml
+++ b/grc/nrsc5_l2_encoder.block.yml
@@ -36,6 +36,14 @@ parameters:
     option_labels: ["Disable", "Select", "Enable"]
     default: nrsc5.blend.ENABLE
     hide: ${ ('none' if num_progs > 0 and first_prog == 0 else 'all') }
+-   id: tx_digital_gain
+    label: TX Digital Audio Gain (dB)
+    dtype: int
+    default: 0
+-   id: debug_logs
+    label: Debug Logs
+    dtype: bool
+    default: 'False'
 
 inputs:
 -   label: hdc
@@ -63,9 +71,10 @@ asserts:
 - ${ 0 <= first_prog <= 7 }
 - ${ 0 <= num_progs <= 8 - first_prog }
 - ${ data_bytes <= (size - 22) // 8 - 1 - ccc_width }
+- ${ -8 <= tx_digital_gain <= 6 }
 
 templates:
     imports: import nrsc5
-    make: nrsc5.l2_encoder(${num_progs}, ${first_prog}, ${size}, ${data_bytes}, ${blend_control}, ccc_width=${ccc_width})
+    make: nrsc5.l2_encoder(${num_progs}, ${first_prog}, ${size}, ${data_bytes}, ${blend_control}, ${tx_digital_gain}, ${debug_logs}, ccc_width=${ccc_width})
 
 file_format: 1
diff --git a/grc/nrsc5_lot_encoder.block.yml b/grc/nrsc5_lot_encoder.block.yml
index 00f287e..560ae7a 100644
--- a/grc/nrsc5_lot_encoder.block.yml
+++ b/grc/nrsc5_lot_encoder.block.yml
@@ -4,7 +4,7 @@ category: '[NRSC-5]'
 
 templates:
   imports: import nrsc5
-  make: nrsc5.lot_encoder(${filename}, ${lot_id}, ${port})
+  make: nrsc5.lot_encoder(${filename}, ${lot_id}, ${port}, ${expiry})
 
 parameters:
 - id: filename
@@ -19,6 +19,10 @@ parameters:
   label: Port
   dtype: int
   default: '0x1001'
+- id: expiry
+  label: Expiry
+  dtype: string
+  default: '45 minutes'
 
 inputs:
 - label: file
@@ -33,4 +37,22 @@ outputs:
   domain: message
   optional: false
 
+documentation: |-
+    Large Object Transfer (LOT) encoder. Transmits files as AAS PDUs.
+
+    Supported file types (auto-detected by magic bytes or extension):
+      - PNG (.png)
+      - JPEG (.jpg, .jpeg)
+      - GIF (.gif) -- both GIF87a and GIF89a
+      - Text (.txt)
+
+    For data-only channels (ports not tied to an audio subchannel's album art
+    or station logo), you must configure a matching data_channel entry in the
+    SIS & SIG encoder block with the same port and LOT ID. Without that SIG
+    advertisement the decoder will not know to reassemble the LOT object.
+
+    Expiry supports relative time strings (e.g. "45 minutes", "2 hours",
+    "1 week") or ISO 8601 datetime with timezone (e.g.
+    "2026-12-31T23:59:59+00:00").
+
 file_format: 1
diff --git a/grc/nrsc5_psd_encoder.block.yml b/grc/nrsc5_psd_encoder.block.yml
index 699ca2e..21ec3b3 100644
--- a/grc/nrsc5_psd_encoder.block.yml
+++ b/grc/nrsc5_psd_encoder.block.yml
@@ -12,11 +12,31 @@ parameters:
 -   id: title
     label: Title
     dtype: string
-    default: Title
+    default: ''
 -   id: artist
     label: Artist
     dtype: string
-    default: Artist
+    default: ''
+-   id: album
+    label: Album
+    dtype: string
+    default: ''
+-   id: genre
+    label: Genre
+    dtype: string
+    default: ''
+-   id: comment_language
+    label: Comment Language
+    dtype: string
+    default: 'eng'
+-   id: comment_short_desc
+    label: Comment Short Description
+    dtype: string
+    default: ''
+-   id: comment_text
+    label: Comment Text
+    dtype: string
+    default: ''
 -   id: bytes_per_frame
     label: Bytes/frame limit
     dtype: int
@@ -39,9 +59,14 @@ asserts:
 
 templates:
     imports: import nrsc5
-    make: nrsc5.psd_encoder(${prog_num}, ${title}, ${artist}, ${bytes_per_frame})
+    make: nrsc5.psd_encoder(${prog_num}, ${title}, ${artist}, ${album}, ${genre}, ${comment_language}, ${comment_short_desc}, ${comment_text}, ${bytes_per_frame})
 
 documentation: |-
-    Accepts messages starting with 'title', 'artist', or 'lot' to set the respective fields.
+    Accepts messages starting with the following to set the respective fields:
+    - Basic metadata: 'title', 'artist', 'album', 'genre'
+    - Comment: 'comment' (text), 'comment_short' (short description), 'comment_language' (ISO 639-2 code)
+    - Commercial: 'commercial_price', 'commercial_valid', 'commercial_url', 'commercial_received', 'commercial_seller', 'commercial_desc'
+    - Reference ID: 'ufid_owner', 'ufid_id'
+    - Album art: 'lot'
 
 file_format: 1
diff --git a/grc/nrsc5_sis_encoder.block.yml b/grc/nrsc5_sis_encoder.block.yml
index f340ae6..bc92fb8 100644
--- a/grc/nrsc5_sis_encoder.block.yml
+++ b/grc/nrsc5_sis_encoder.block.yml
@@ -130,6 +130,244 @@ parameters:
     options: ['False', 'True']
     option_labels: ['Off', 'On']
     hide: part
+-   id: num_data_channels
+    label: Data Channels
+    dtype: int
+    default: 0
+    options: [0, 1, 2, 3, 4, 5, 6, 7, 8]
+    hide: part
+-   id: dc0_port
+    label: Data Channel 0 Port
+    dtype: int
+    default: '0x1010'
+    hide: ${ ('part' if int(num_data_channels) >= 1 else 'all') }
+-   id: dc0_lot_id
+    label: Data Channel 0 LOT ID
+    dtype: int
+    default: 1010
+    hide: ${ ('part' if int(num_data_channels) >= 1 else 'all') }
+-   id: dc0_sdt
+    label: Data Channel 0 Service Data Type
+    dtype: enum
+    options: [nrsc5.service_data_type.NON_SPECIFIC, nrsc5.service_data_type.NEWS, nrsc5.service_data_type.SPORTS, nrsc5.service_data_type.WEATHER, nrsc5.service_data_type.EMERGENCY, nrsc5.service_data_type.TRAFFIC, nrsc5.service_data_type.IMAGE_MAPS, nrsc5.service_data_type.TEXT, nrsc5.service_data_type.ADVERTISING, nrsc5.service_data_type.FINANCIAL, nrsc5.service_data_type.STOCK_TICKER, nrsc5.service_data_type.NAVIGATION, nrsc5.service_data_type.ELECTRONIC_PROGRAM_GUIDE, nrsc5.service_data_type.AUDIO, nrsc5.service_data_type.PRIVATE_DATA_NETWORK, nrsc5.service_data_type.SERVICE_MAINTENANCE, nrsc5.service_data_type.HD_RADIO_SYSTEM_SERVICES, nrsc5.service_data_type.AUDIO_RELATED_DATA]
+    option_labels: ["Non-Specific", "News", "Sports", "Weather", "Emergency", "Traffic", "Image Maps", "Text", "Advertising", "Financial", "Stock Ticker", "Navigation", "EPG", "Audio", "Private Data", "Service Maintenance", "HD Radio System Services", "Audio Related Data"]
+    default: nrsc5.service_data_type.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 1 else 'all') }
+-   id: dc0_mime
+    label: Data Channel 0 MIME Type
+    dtype: enum
+    options: [nrsc5.mime_hash.TEXT, nrsc5.mime_hash.PNG, nrsc5.mime_hash.JPEG, nrsc5.mime_hash.GIF, nrsc5.mime_hash.PRIMARY_IMAGE, nrsc5.mime_hash.STATION_LOGO]
+    option_labels: ["Text (.txt)", "PNG Image", "JPEG Image", "GIF Image", "Primary Image", "Station Logo"]
+    default: nrsc5.mime_hash.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 1 else 'all') }
+-   id: dc0_name
+    label: Data Channel 0 Name
+    dtype: string
+    default: ""
+    hide: ${ ('part' if int(num_data_channels) >= 1 else 'all') }
+-   id: dc1_port
+    label: Data Channel 1 Port
+    dtype: int
+    default: '0x1011'
+    hide: ${ ('part' if int(num_data_channels) >= 2 else 'all') }
+-   id: dc1_lot_id
+    label: Data Channel 1 LOT ID
+    dtype: int
+    default: 1011
+    hide: ${ ('part' if int(num_data_channels) >= 2 else 'all') }
+-   id: dc1_sdt
+    label: Data Channel 1 Service Data Type
+    dtype: enum
+    options: [nrsc5.service_data_type.NON_SPECIFIC, nrsc5.service_data_type.NEWS, nrsc5.service_data_type.SPORTS, nrsc5.service_data_type.WEATHER, nrsc5.service_data_type.EMERGENCY, nrsc5.service_data_type.TRAFFIC, nrsc5.service_data_type.IMAGE_MAPS, nrsc5.service_data_type.TEXT, nrsc5.service_data_type.ADVERTISING, nrsc5.service_data_type.FINANCIAL, nrsc5.service_data_type.STOCK_TICKER, nrsc5.service_data_type.NAVIGATION, nrsc5.service_data_type.ELECTRONIC_PROGRAM_GUIDE, nrsc5.service_data_type.AUDIO, nrsc5.service_data_type.PRIVATE_DATA_NETWORK, nrsc5.service_data_type.SERVICE_MAINTENANCE, nrsc5.service_data_type.HD_RADIO_SYSTEM_SERVICES, nrsc5.service_data_type.AUDIO_RELATED_DATA]
+    option_labels: ["Non-Specific", "News", "Sports", "Weather", "Emergency", "Traffic", "Image Maps", "Text", "Advertising", "Financial", "Stock Ticker", "Navigation", "EPG", "Audio", "Private Data", "Service Maintenance", "HD Radio System Services", "Audio Related Data"]
+    default: nrsc5.service_data_type.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 2 else 'all') }
+-   id: dc1_mime
+    label: Data Channel 1 MIME Type
+    dtype: enum
+    options: [nrsc5.mime_hash.TEXT, nrsc5.mime_hash.PNG, nrsc5.mime_hash.JPEG, nrsc5.mime_hash.GIF, nrsc5.mime_hash.PRIMARY_IMAGE, nrsc5.mime_hash.STATION_LOGO]
+    option_labels: ["Text (.txt)", "PNG Image", "JPEG Image", "GIF Image", "Primary Image", "Station Logo"]
+    default: nrsc5.mime_hash.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 2 else 'all') }
+-   id: dc1_name
+    label: Data Channel 1 Name
+    dtype: string
+    default: ""
+    hide: ${ ('part' if int(num_data_channels) >= 2 else 'all') }
+-   id: dc2_port
+    label: Data Channel 2 Port
+    dtype: int
+    default: '0x1012'
+    hide: ${ ('part' if int(num_data_channels) >= 3 else 'all') }
+-   id: dc2_lot_id
+    label: Data Channel 2 LOT ID
+    dtype: int
+    default: 1012
+    hide: ${ ('part' if int(num_data_channels) >= 3 else 'all') }
+-   id: dc2_sdt
+    label: Data Channel 2 Service Data Type
+    dtype: enum
+    options: [nrsc5.service_data_type.NON_SPECIFIC, nrsc5.service_data_type.NEWS, nrsc5.service_data_type.SPORTS, nrsc5.service_data_type.WEATHER, nrsc5.service_data_type.EMERGENCY, nrsc5.service_data_type.TRAFFIC, nrsc5.service_data_type.IMAGE_MAPS, nrsc5.service_data_type.TEXT, nrsc5.service_data_type.ADVERTISING, nrsc5.service_data_type.FINANCIAL, nrsc5.service_data_type.STOCK_TICKER, nrsc5.service_data_type.NAVIGATION, nrsc5.service_data_type.ELECTRONIC_PROGRAM_GUIDE, nrsc5.service_data_type.AUDIO, nrsc5.service_data_type.PRIVATE_DATA_NETWORK, nrsc5.service_data_type.SERVICE_MAINTENANCE, nrsc5.service_data_type.HD_RADIO_SYSTEM_SERVICES, nrsc5.service_data_type.AUDIO_RELATED_DATA]
+    option_labels: ["Non-Specific", "News", "Sports", "Weather", "Emergency", "Traffic", "Image Maps", "Text", "Advertising", "Financial", "Stock Ticker", "Navigation", "EPG", "Audio", "Private Data", "Service Maintenance", "HD Radio System Services", "Audio Related Data"]
+    default: nrsc5.service_data_type.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 3 else 'all') }
+-   id: dc2_mime
+    label: Data Channel 2 MIME Type
+    dtype: enum
+    options: [nrsc5.mime_hash.TEXT, nrsc5.mime_hash.PNG, nrsc5.mime_hash.JPEG, nrsc5.mime_hash.GIF, nrsc5.mime_hash.PRIMARY_IMAGE, nrsc5.mime_hash.STATION_LOGO]
+    option_labels: ["Text (.txt)", "PNG Image", "JPEG Image", "GIF Image", "Primary Image", "Station Logo"]
+    default: nrsc5.mime_hash.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 3 else 'all') }
+-   id: dc2_name
+    label: Data Channel 2 Name
+    dtype: string
+    default: ""
+    hide: ${ ('part' if int(num_data_channels) >= 3 else 'all') }
+-   id: dc3_port
+    label: Data Channel 3 Port
+    dtype: int
+    default: '0x1013'
+    hide: ${ ('part' if int(num_data_channels) >= 4 else 'all') }
+-   id: dc3_lot_id
+    label: Data Channel 3 LOT ID
+    dtype: int
+    default: 1013
+    hide: ${ ('part' if int(num_data_channels) >= 4 else 'all') }
+-   id: dc3_sdt
+    label: Data Channel 3 Service Data Type
+    dtype: enum
+    options: [nrsc5.service_data_type.NON_SPECIFIC, nrsc5.service_data_type.NEWS, nrsc5.service_data_type.SPORTS, nrsc5.service_data_type.WEATHER, nrsc5.service_data_type.EMERGENCY, nrsc5.service_data_type.TRAFFIC, nrsc5.service_data_type.IMAGE_MAPS, nrsc5.service_data_type.TEXT, nrsc5.service_data_type.ADVERTISING, nrsc5.service_data_type.FINANCIAL, nrsc5.service_data_type.STOCK_TICKER, nrsc5.service_data_type.NAVIGATION, nrsc5.service_data_type.ELECTRONIC_PROGRAM_GUIDE, nrsc5.service_data_type.AUDIO, nrsc5.service_data_type.PRIVATE_DATA_NETWORK, nrsc5.service_data_type.SERVICE_MAINTENANCE, nrsc5.service_data_type.HD_RADIO_SYSTEM_SERVICES, nrsc5.service_data_type.AUDIO_RELATED_DATA]
+    option_labels: ["Non-Specific", "News", "Sports", "Weather", "Emergency", "Traffic", "Image Maps", "Text", "Advertising", "Financial", "Stock Ticker", "Navigation", "EPG", "Audio", "Private Data", "Service Maintenance", "HD Radio System Services", "Audio Related Data"]
+    default: nrsc5.service_data_type.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 4 else 'all') }
+-   id: dc3_mime
+    label: Data Channel 3 MIME Type
+    dtype: enum
+    options: [nrsc5.mime_hash.TEXT, nrsc5.mime_hash.PNG, nrsc5.mime_hash.JPEG, nrsc5.mime_hash.GIF, nrsc5.mime_hash.PRIMARY_IMAGE, nrsc5.mime_hash.STATION_LOGO]
+    option_labels: ["Text (.txt)", "PNG Image", "JPEG Image", "GIF Image", "Primary Image", "Station Logo"]
+    default: nrsc5.mime_hash.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 4 else 'all') }
+-   id: dc3_name
+    label: Data Channel 3 Name
+    dtype: string
+    default: ""
+    hide: ${ ('part' if int(num_data_channels) >= 4 else 'all') }
+-   id: dc4_port
+    label: Data Channel 4 Port
+    dtype: int
+    default: '0x1014'
+    hide: ${ ('part' if int(num_data_channels) >= 5 else 'all') }
+-   id: dc4_lot_id
+    label: Data Channel 4 LOT ID
+    dtype: int
+    default: 1014
+    hide: ${ ('part' if int(num_data_channels) >= 5 else 'all') }
+-   id: dc4_sdt
+    label: Data Channel 4 Service Data Type
+    dtype: enum
+    options: [nrsc5.service_data_type.NON_SPECIFIC, nrsc5.service_data_type.NEWS, nrsc5.service_data_type.SPORTS, nrsc5.service_data_type.WEATHER, nrsc5.service_data_type.EMERGENCY, nrsc5.service_data_type.TRAFFIC, nrsc5.service_data_type.IMAGE_MAPS, nrsc5.service_data_type.TEXT, nrsc5.service_data_type.ADVERTISING, nrsc5.service_data_type.FINANCIAL, nrsc5.service_data_type.STOCK_TICKER, nrsc5.service_data_type.NAVIGATION, nrsc5.service_data_type.ELECTRONIC_PROGRAM_GUIDE, nrsc5.service_data_type.AUDIO, nrsc5.service_data_type.PRIVATE_DATA_NETWORK, nrsc5.service_data_type.SERVICE_MAINTENANCE, nrsc5.service_data_type.HD_RADIO_SYSTEM_SERVICES, nrsc5.service_data_type.AUDIO_RELATED_DATA]
+    option_labels: ["Non-Specific", "News", "Sports", "Weather", "Emergency", "Traffic", "Image Maps", "Text", "Advertising", "Financial", "Stock Ticker", "Navigation", "EPG", "Audio", "Private Data", "Service Maintenance", "HD Radio System Services", "Audio Related Data"]
+    default: nrsc5.service_data_type.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 5 else 'all') }
+-   id: dc4_mime
+    label: Data Channel 4 MIME Type
+    dtype: enum
+    options: [nrsc5.mime_hash.TEXT, nrsc5.mime_hash.PNG, nrsc5.mime_hash.JPEG, nrsc5.mime_hash.GIF, nrsc5.mime_hash.PRIMARY_IMAGE, nrsc5.mime_hash.STATION_LOGO]
+    option_labels: ["Text (.txt)", "PNG Image", "JPEG Image", "GIF Image", "Primary Image", "Station Logo"]
+    default: nrsc5.mime_hash.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 5 else 'all') }
+-   id: dc4_name
+    label: Data Channel 4 Name
+    dtype: string
+    default: ""
+    hide: ${ ('part' if int(num_data_channels) >= 5 else 'all') }
+-   id: dc5_port
+    label: Data Channel 5 Port
+    dtype: int
+    default: '0x1015'
+    hide: ${ ('part' if int(num_data_channels) >= 6 else 'all') }
+-   id: dc5_lot_id
+    label: Data Channel 5 LOT ID
+    dtype: int
+    default: 1015
+    hide: ${ ('part' if int(num_data_channels) >= 6 else 'all') }
+-   id: dc5_sdt
+    label: Data Channel 5 Service Data Type
+    dtype: enum
+    options: [nrsc5.service_data_type.NON_SPECIFIC, nrsc5.service_data_type.NEWS, nrsc5.service_data_type.SPORTS, nrsc5.service_data_type.WEATHER, nrsc5.service_data_type.EMERGENCY, nrsc5.service_data_type.TRAFFIC, nrsc5.service_data_type.IMAGE_MAPS, nrsc5.service_data_type.TEXT, nrsc5.service_data_type.ADVERTISING, nrsc5.service_data_type.FINANCIAL, nrsc5.service_data_type.STOCK_TICKER, nrsc5.service_data_type.NAVIGATION, nrsc5.service_data_type.ELECTRONIC_PROGRAM_GUIDE, nrsc5.service_data_type.AUDIO, nrsc5.service_data_type.PRIVATE_DATA_NETWORK, nrsc5.service_data_type.SERVICE_MAINTENANCE, nrsc5.service_data_type.HD_RADIO_SYSTEM_SERVICES, nrsc5.service_data_type.AUDIO_RELATED_DATA]
+    option_labels: ["Non-Specific", "News", "Sports", "Weather", "Emergency", "Traffic", "Image Maps", "Text", "Advertising", "Financial", "Stock Ticker", "Navigation", "EPG", "Audio", "Private Data", "Service Maintenance", "HD Radio System Services", "Audio Related Data"]
+    default: nrsc5.service_data_type.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 6 else 'all') }
+-   id: dc5_mime
+    label: Data Channel 5 MIME Type
+    dtype: enum
+    options: [nrsc5.mime_hash.TEXT, nrsc5.mime_hash.PNG, nrsc5.mime_hash.JPEG, nrsc5.mime_hash.GIF, nrsc5.mime_hash.PRIMARY_IMAGE, nrsc5.mime_hash.STATION_LOGO]
+    option_labels: ["Text (.txt)", "PNG Image", "JPEG Image", "GIF Image", "Primary Image", "Station Logo"]
+    default: nrsc5.mime_hash.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 6 else 'all') }
+-   id: dc5_name
+    label: Data Channel 5 Name
+    dtype: string
+    default: ""
+    hide: ${ ('part' if int(num_data_channels) >= 6 else 'all') }
+-   id: dc6_port
+    label: Data Channel 6 Port
+    dtype: int
+    default: '0x1016'
+    hide: ${ ('part' if int(num_data_channels) >= 7 else 'all') }
+-   id: dc6_lot_id
+    label: Data Channel 6 LOT ID
+    dtype: int
+    default: 1016
+    hide: ${ ('part' if int(num_data_channels) >= 7 else 'all') }
+-   id: dc6_sdt
+    label: Data Channel 6 Service Data Type
+    dtype: enum
+    options: [nrsc5.service_data_type.NON_SPECIFIC, nrsc5.service_data_type.NEWS, nrsc5.service_data_type.SPORTS, nrsc5.service_data_type.WEATHER, nrsc5.service_data_type.EMERGENCY, nrsc5.service_data_type.TRAFFIC, nrsc5.service_data_type.IMAGE_MAPS, nrsc5.service_data_type.TEXT, nrsc5.service_data_type.ADVERTISING, nrsc5.service_data_type.FINANCIAL, nrsc5.service_data_type.STOCK_TICKER, nrsc5.service_data_type.NAVIGATION, nrsc5.service_data_type.ELECTRONIC_PROGRAM_GUIDE, nrsc5.service_data_type.AUDIO, nrsc5.service_data_type.PRIVATE_DATA_NETWORK, nrsc5.service_data_type.SERVICE_MAINTENANCE, nrsc5.service_data_type.HD_RADIO_SYSTEM_SERVICES, nrsc5.service_data_type.AUDIO_RELATED_DATA]
+    option_labels: ["Non-Specific", "News", "Sports", "Weather", "Emergency", "Traffic", "Image Maps", "Text", "Advertising", "Financial", "Stock Ticker", "Navigation", "EPG", "Audio", "Private Data", "Service Maintenance", "HD Radio System Services", "Audio Related Data"]
+    default: nrsc5.service_data_type.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 7 else 'all') }
+-   id: dc6_mime
+    label: Data Channel 6 MIME Type
+    dtype: enum
+    options: [nrsc5.mime_hash.TEXT, nrsc5.mime_hash.PNG, nrsc5.mime_hash.JPEG, nrsc5.mime_hash.GIF, nrsc5.mime_hash.PRIMARY_IMAGE, nrsc5.mime_hash.STATION_LOGO]
+    option_labels: ["Text (.txt)", "PNG Image", "JPEG Image", "GIF Image", "Primary Image", "Station Logo"]
+    default: nrsc5.mime_hash.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 7 else 'all') }
+-   id: dc6_name
+    label: Data Channel 6 Name
+    dtype: string
+    default: ""
+    hide: ${ ('part' if int(num_data_channels) >= 7 else 'all') }
+-   id: dc7_port
+    label: Data Channel 7 Port
+    dtype: int
+    default: '0x1017'
+    hide: ${ ('part' if int(num_data_channels) >= 8 else 'all') }
+-   id: dc7_lot_id
+    label: Data Channel 7 LOT ID
+    dtype: int
+    default: 1017
+    hide: ${ ('part' if int(num_data_channels) >= 8 else 'all') }
+-   id: dc7_sdt
+    label: Data Channel 7 Service Data Type
+    dtype: enum
+    options: [nrsc5.service_data_type.NON_SPECIFIC, nrsc5.service_data_type.NEWS, nrsc5.service_data_type.SPORTS, nrsc5.service_data_type.WEATHER, nrsc5.service_data_type.EMERGENCY, nrsc5.service_data_type.TRAFFIC, nrsc5.service_data_type.IMAGE_MAPS, nrsc5.service_data_type.TEXT, nrsc5.service_data_type.ADVERTISING, nrsc5.service_data_type.FINANCIAL, nrsc5.service_data_type.STOCK_TICKER, nrsc5.service_data_type.NAVIGATION, nrsc5.service_data_type.ELECTRONIC_PROGRAM_GUIDE, nrsc5.service_data_type.AUDIO, nrsc5.service_data_type.PRIVATE_DATA_NETWORK, nrsc5.service_data_type.SERVICE_MAINTENANCE, nrsc5.service_data_type.HD_RADIO_SYSTEM_SERVICES, nrsc5.service_data_type.AUDIO_RELATED_DATA]
+    option_labels: ["Non-Specific", "News", "Sports", "Weather", "Emergency", "Traffic", "Image Maps", "Text", "Advertising", "Financial", "Stock Ticker", "Navigation", "EPG", "Audio", "Private Data", "Service Maintenance", "HD Radio System Services", "Audio Related Data"]
+    default: nrsc5.service_data_type.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 8 else 'all') }
+-   id: dc7_mime
+    label: Data Channel 7 MIME Type
+    dtype: enum
+    options: [nrsc5.mime_hash.TEXT, nrsc5.mime_hash.PNG, nrsc5.mime_hash.JPEG, nrsc5.mime_hash.GIF, nrsc5.mime_hash.PRIMARY_IMAGE, nrsc5.mime_hash.STATION_LOGO]
+    option_labels: ["Text (.txt)", "PNG Image", "JPEG Image", "GIF Image", "Primary Image", "Station Logo"]
+    default: nrsc5.mime_hash.TEXT
+    hide: ${ ('part' if int(num_data_channels) >= 8 else 'all') }
+-   id: dc7_name
+    label: Data Channel 7 Name
+    dtype: string
+    default: ""
+    hide: ${ ('part' if int(num_data_channels) >= 8 else 'all') }
 -   id: latitude
     label: Latitude
     dtype: real
@@ -155,6 +393,41 @@ parameters:
     dtype: int
     default: 0
     hide: part
+-   id: exciter_manufacturer_id
+    label: Exciter Manufacturer ID
+    dtype: string
+    default: CS
+    hide: part
+-   id: importer_manufacturer_id
+    label: Importer Manufacturer ID
+    dtype: string
+    default: CS
+    hide: part
+-   id: exciter_core_ver
+    label: Exciter Core Version (L1.L2.L3.L4)
+    dtype: string
+    default: "1.0.0.0"
+    hide: part
+-   id: exciter_mfr_ver
+    label: Exciter Mfr Version (L1.L2.L3.L4)
+    dtype: string
+    default: "1.0.0.0"
+    hide: part
+-   id: importer_core_ver
+    label: Importer Core Version (L1.L2.L3.L4)
+    dtype: string
+    default: "1.0.0.0"
+    hide: part
+-   id: importer_mfr_ver
+    label: Importer Mfr Version (L1.L2.L3.L4)
+    dtype: string
+    default: "1.0.0.0"
+    hide: part
+-   id: importer_config_number
+    label: Importer Configuration Number
+    dtype: int
+    default: 0
+    hide: part
 
 inputs:
 -   domain: message
@@ -182,9 +455,57 @@ asserts:
 -   ${ -90 <= latitude <= 90 }
 -   ${ -180 <= longitude <= 180 }
 -   ${ len(country_code) == 2 }
+-   ${ len(exciter_manufacturer_id) == 2 }
+-   ${ len(importer_manufacturer_id) == 2 }
 
 templates:
     imports: import nrsc5
-    make: nrsc5.sis_encoder(mode=${mode}, short_name=${short_name}, slogan=${slogan}, message=${message}, program_names=[${program_name0}${ ', '+program_name1 if int(num_programs) >= 2 else '' }${ ', '+program_name2 if int(num_programs) >= 3 else '' }${ ', '+program_name3 if int(num_programs) >= 4 else '' }${ ', '+program_name4 if int(num_programs) >= 5 else '' }${ ', '+program_name5 if int(num_programs) >= 6 else '' }${ ', '+program_name6 if int(num_programs) >= 7 else '' }${ ', '+program_name7 if int(num_programs) >= 8 else '' }], program_types=[${program_type0}${ ', '+program_type1 if int(num_programs) >= 2 else '' }${ ', '+program_type2 if int(num_programs) >= 3 else '' }${ ', '+program_type3 if int(num_programs) >= 4 else '' }${ ', '+program_type4 if int(num_programs) >= 5 else '' }${ ', '+program_type5 if int(num_programs) >= 6 else '' }${ ', '+program_type6 if int(num_programs) >= 7 else '' }${ ', '+program_type7 if int(num_programs) >= 8 else '' }], data_types=[${'nrsc5.service_data_type.EMERGENCY, ' if emergency_alerts == 'True' else ''}], data_mime_types=[${'0x444, ' if emergency_alerts == 'True' else ''}], latitude=${latitude}, longitude=${longitude}, altitude=${altitude}, country_code=${country_code}, fcc_facility_id=${fcc_facility_id})
+    make: |
+        nrsc5.sis_encoder(
+            mode=${mode},
+            short_name=${short_name},
+            slogan=${slogan},
+            message=${message},
+            program_names=[${program_name0}${ ', '+program_name1 if int(num_programs) >= 2 else '' }${ ', '+program_name2 if int(num_programs) >= 3 else '' }${ ', '+program_name3 if int(num_programs) >= 4 else '' }${ ', '+program_name4 if int(num_programs) >= 5 else '' }${ ', '+program_name5 if int(num_programs) >= 6 else '' }${ ', '+program_name6 if int(num_programs) >= 7 else '' }${ ', '+program_name7 if int(num_programs) >= 8 else '' }],
+            program_types=[${program_type0}${ ', '+program_type1 if int(num_programs) >= 2 else '' }${ ', '+program_type2 if int(num_programs) >= 3 else '' }${ ', '+program_type3 if int(num_programs) >= 4 else '' }${ ', '+program_type4 if int(num_programs) >= 5 else '' }${ ', '+program_type5 if int(num_programs) >= 6 else '' }${ ', '+program_type6 if int(num_programs) >= 7 else '' }${ ', '+program_type7 if int(num_programs) >= 8 else '' }],
+            data_types=[${'nrsc5.service_data_type.EMERGENCY, ' if emergency_alerts == 'True' else ''}],
+            data_mime_types=[${'0x444, ' if emergency_alerts == 'True' else ''}],
+            latitude=${latitude},
+            longitude=${longitude},
+            altitude=${altitude},
+            country_code=${country_code},
+            fcc_facility_id=${fcc_facility_id},
+            data_channels=[${ 'nrsc5.data_channel_config('+dc0_port+', '+dc0_lot_id+', int('+dc0_sdt+'), int('+dc0_mime+'), '+dc0_name+'), ' if int(num_data_channels) >= 1 else '' }${ 'nrsc5.data_channel_config('+dc1_port+', '+dc1_lot_id+', int('+dc1_sdt+'), int('+dc1_mime+'), '+dc1_name+'), ' if int(num_data_channels) >= 2 else '' }${ 'nrsc5.data_channel_config('+dc2_port+', '+dc2_lot_id+', int('+dc2_sdt+'), int('+dc2_mime+'), '+dc2_name+'), ' if int(num_data_channels) >= 3 else '' }${ 'nrsc5.data_channel_config('+dc3_port+', '+dc3_lot_id+', int('+dc3_sdt+'), int('+dc3_mime+'), '+dc3_name+'), ' if int(num_data_channels) >= 4 else '' }${ 'nrsc5.data_channel_config('+dc4_port+', '+dc4_lot_id+', int('+dc4_sdt+'), int('+dc4_mime+'), '+dc4_name+'), ' if int(num_data_channels) >= 5 else '' }${ 'nrsc5.data_channel_config('+dc5_port+', '+dc5_lot_id+', int('+dc5_sdt+'), int('+dc5_mime+'), '+dc5_name+'), ' if int(num_data_channels) >= 6 else '' }${ 'nrsc5.data_channel_config('+dc6_port+', '+dc6_lot_id+', int('+dc6_sdt+'), int('+dc6_mime+'), '+dc6_name+'), ' if int(num_data_channels) >= 7 else '' }${ 'nrsc5.data_channel_config('+dc7_port+', '+dc7_lot_id+', int('+dc7_sdt+'), int('+dc7_mime+'), '+dc7_name+'), ' if int(num_data_channels) >= 8 else '' }],
+            exciter_manufacturer_id=${exciter_manufacturer_id},
+            importer_manufacturer_id=${importer_manufacturer_id},
+            exciter_core_version=[int(x) for x in ${exciter_core_ver}.split('.')],
+            exciter_mfr_version=[int(x) for x in ${exciter_mfr_ver}.split('.')],
+            importer_core_version=[int(x) for x in ${importer_core_ver}.split('.')],
+            importer_mfr_version=[int(x) for x in ${importer_mfr_ver}.split('.')],
+            importer_configuration_number=${importer_config_number})
+
+documentation: |-
+    SIS (Station Information Service) and SIG (Station Information Guide) encoder.
+
+    Data Channels: Configure data-only channels for transmitting LOT files
+    independent of audio subchannels. Each data channel is advertised in SIG
+    with its port, LOT ID, Service Data Type, and MIME Type Hash so decoders
+    can properly reassemble the LOT objects.
+
+    SIS Parameters (runtime via TCP command port):
+      set_param|<index>|<value>
+        Index 0:  Leap Second Offset (pending|current or 0xPPCC)
+        Index 1:  Leap Second ALFN LSB
+        Index 2:  Leap Second ALFN MSB
+        Index 3:  Local Time (utc_offset_minutes[|dst_sched|dst_local|dst_regional])
+        Index 4:  Exciter Manufacturer ID (2 chars)
+        Index 5:  Exciter Core Version (L1.L2.L3)
+        Index 6:  Exciter Mfr Version (L1.L2.L3)
+        Index 7:  Exciter V4+Status (core4.mfr4.core_status.mfr_status)
+        Index 8:  Importer Manufacturer ID (2 chars)
+        Index 9:  Importer Core Version (L1.L2.L3)
+        Index 10: Importer Mfr Version (L1.L2.L3)
+        Index 11: Importer V4+Status (core4.mfr4.core_status.mfr_status)
+        Index 12: Importer Configuration Number (0-65535)
 
 file_format: 1
diff --git a/include/nrsc5/api.h b/include/nrsc5/api.h
index 67d3422..90cff34 100644
--- a/include/nrsc5/api.h
+++ b/include/nrsc5/api.h
@@ -13,6 +13,7 @@
 
 #include <gnuradio/attributes.h>
 #include <cstdint>
+#include <string>
 
 #ifdef gnuradio_nrsc5_EXPORTS
 #define NRSC5_API __GR_ATTR_EXPORT
@@ -34,6 +35,7 @@ enum class mime_hash : uint32_t {
     TEXT = 0xBB492AAC,
     JPEG = 0x1E653E9C,
     PNG = 0x4F328CA0,
+    GIF = 0x87A4FD95,
     TTN_TPEG_1 = 0xB39EBEB2,
     TTN_TPEG_2 = 0x4EB03469,
     TTN_TPEG_3 = 0x52103469,
@@ -41,6 +43,27 @@ enum class mime_hash : uint32_t {
     TTN_STM_WEATHER = 0xEF042E96
 };
 
+/* Configuration for a data-only channel advertised via SIG/SIM.
+ * Each entry causes:
+ *   - A DATA service descriptor in the Service Information Message (SIM)
+ *   - A DATA_COMPONENT entry in the SIG with the correct port, SDT, and MIME hash
+ *   - A DATA_INFO entry so decoders can reassemble LOT objects on that port
+ *
+ * port          AAS port number the LOT encoder is transmitting on
+ * lot_id        LOT object ID used by the LOT encoder on this port
+ * sdt           Service Data Type (from service_data_type enum)
+ * mime          MIME type hash (from mime_hash enum) -- set to 0 to auto-select
+ *              from the file extension at runtime
+ * name          Service name shown in decoder (e.g., "Traffic", "Weather")
+ */
+struct data_channel_config {
+    uint16_t port;
+    uint16_t lot_id;
+    unsigned int sdt;    // service_data_type value
+    uint32_t mime;       // mime_hash value; 0 = auto
+    std::string name;
+};
+
 } /* namespace nrsc5 */
 } /* namespace gr */
 
diff --git a/include/nrsc5/hdc_encoder.h b/include/nrsc5/hdc_encoder.h
index edcc43b..ca23181 100644
--- a/include/nrsc5/hdc_encoder.h
+++ b/include/nrsc5/hdc_encoder.h
@@ -31,8 +31,13 @@ class NRSC5_API hdc_encoder : virtual public gr::block
      * constructor is in a private implementation
      * class. nrsc5::hdc_encoder::make is the public interface for
      * creating new instances.
+     *
+     * \param channels Number of audio channels (1 or 2)
+     * \param bitrate Bitrate in bits per second
+     * \param use_parametric_stereo Use Parametric Stereo (AOT 128) instead of Regular Stereo (AOT 127)
+     * \param tx_digital_gain TX Digital Audio Gain in dB (-8 to +6)
      */
-    static sptr make(int channels = 2, int bitrate = 64000);
+    static sptr make(int channels = 2, int bitrate = 64000, bool use_parametric_stereo = false, int tx_digital_gain = 0);
 };
 
 } // namespace nrsc5
diff --git a/include/nrsc5/l2_encoder.h b/include/nrsc5/l2_encoder.h
index dd3599a..eae7deb 100644
--- a/include/nrsc5/l2_encoder.h
+++ b/include/nrsc5/l2_encoder.h
@@ -33,12 +33,23 @@ class NRSC5_API l2_encoder : virtual public gr::block
      * constructor is in a private implementation
      * class. nrsc5::l2_encoder::make is the public interface for
      * creating new instances.
+     *
+     * \param num_progs Number of programs
+     * \param first_prog First program number
+     * \param size PDU size in bits
+     * \param data_bytes Number of data bytes
+     * \param blend_control Blend control mode
+     * \param tx_digital_gain TX Digital Audio Gain in dB (range: -8 to +6 dB)
+     * \param debug_logs Enable debug logging for L2 Lot ID port operations
+     * \param ccc_width Configuration control channel width (1-30 bytes)
      */
     static sptr make(const int num_progs,
                      const int first_prog,
                      const int size,
                      const int data_bytes = 0,
                      const blend blend_control = blend::ENABLE,
+                     const int tx_digital_gain = 0,
+                     const bool debug_logs = false,
                      const int ccc_width = 24);
 };
 
diff --git a/include/nrsc5/psd_encoder.h b/include/nrsc5/psd_encoder.h
index d14f311..b89e205 100644
--- a/include/nrsc5/psd_encoder.h
+++ b/include/nrsc5/psd_encoder.h
@@ -33,8 +33,13 @@ class NRSC5_API psd_encoder : virtual public gr::sync_block
      * creating new instances.
      */
     static sptr make(const int prog_num,
-                     const std::string& title,
-                     const std::string& artist,
+                     const std::string& title = "",
+                     const std::string& artist = "",
+                     const std::string& album = "",
+                     const std::string& genre = "",
+                     const std::string& comment_language = "",
+                     const std::string& comment_short_desc = "",
+                     const std::string& comment_text = "",
                      const int bytes_per_frame = 0);
 };
 
diff --git a/include/nrsc5/sis_encoder.h b/include/nrsc5/sis_encoder.h
index 9f376bb..70c24ac 100644
--- a/include/nrsc5/sis_encoder.h
+++ b/include/nrsc5/sis_encoder.h
@@ -103,7 +103,15 @@ class NRSC5_API sis_encoder : virtual public gr::sync_block
          const float longitude = -74.0445,
          const float altitude = 93.0,
          const std::string& country_code = "US",
-         const unsigned int fcc_facility_id = 0);
+         const unsigned int fcc_facility_id = 0,
+         const std::vector<data_channel_config> data_channels = {},
+         const std::string& exciter_manufacturer_id = "CS",
+         const std::string& importer_manufacturer_id = "CS",
+         const std::vector<unsigned int> exciter_core_version = { 1, 0, 0, 0 },
+         const std::vector<unsigned int> exciter_mfr_version = { 1, 0, 0, 0 },
+         const std::vector<unsigned int> importer_core_version = { 1, 0, 0, 0 },
+         const std::vector<unsigned int> importer_mfr_version = { 1, 0, 0, 0 },
+         const unsigned int importer_configuration_number = 0);
 };
 
 } // namespace nrsc5
diff --git a/lib/hdc_encoder_impl.cc b/lib/hdc_encoder_impl.cc
index 85f27a5..37649e0 100644
--- a/lib/hdc_encoder_impl.cc
+++ b/lib/hdc_encoder_impl.cc
@@ -15,16 +15,16 @@
 namespace gr {
 namespace nrsc5 {
 
-hdc_encoder::sptr hdc_encoder::make(int channels, int bitrate)
+hdc_encoder::sptr hdc_encoder::make(int channels, int bitrate, bool use_parametric_stereo, int tx_digital_gain)
 {
-    return gnuradio::get_initial_sptr(new hdc_encoder_impl(channels, bitrate));
+    return gnuradio::get_initial_sptr(new hdc_encoder_impl(channels, bitrate, use_parametric_stereo, tx_digital_gain));
 }
 
 
 /*
  * The private constructor
  */
-hdc_encoder_impl::hdc_encoder_impl(int channels, int bitrate)
+hdc_encoder_impl::hdc_encoder_impl(int channels, int bitrate, bool use_parametric_stereo, int tx_digital_gain)
     : gr::block("hdc_encoder",
                 gr::io_signature::make(1, 2, sizeof(float)),
                 gr::io_signature::make(1, 1, sizeof(unsigned char)))
@@ -33,10 +33,36 @@ hdc_encoder_impl::hdc_encoder_impl(int channels, int bitrate)
     bytes_per_frame = bitrate * SAMPLES_PER_FRAME / HDC_SAMPLE_RATE / 8;
     set_relative_rate((double)bytes_per_frame / SAMPLES_PER_FRAME);
 
+    // Validate and clamp TX Digital Audio Gain to valid range (-8 to +6 dB)
+    if (tx_digital_gain < -8) {
+        this->tx_digital_gain = -8;
+        fprintf(stderr, "Warning: TX Digital Audio Gain clamped to minimum -8 dB\n");
+    } else if (tx_digital_gain > 6) {
+        this->tx_digital_gain = 6;
+        fprintf(stderr, "Warning: TX Digital Audio Gain clamped to maximum +6 dB\n");
+    } else {
+        this->tx_digital_gain = tx_digital_gain;
+    }
+
+    // Convert dB to linear multiplier: multiplier = 10^(dB/20)
+    gain_multiplier = pow(10.0, this->tx_digital_gain / 20.0);
+
     int vbr = 0;
     int afterburner = 1;
     CHANNEL_MODE mode;
     AACENC_InfoStruct info = { 0 };
+
+    // Determine AOT based on parametric stereo setting
+    // AOT 127 = HE-AAC v1 (Regular Stereo)
+    // AOT 128 = HE-AAC v2 with Parametric Stereo (PS)
+    int aot = use_parametric_stereo ? 128 : 127;
+
+    // Note: Parametric Stereo (AOT 128) is only applicable for stereo
+    if (use_parametric_stereo && channels != 2) {
+        fprintf(stderr, "Warning: Parametric Stereo requires 2 channels, using Regular Stereo (AOT 127) instead\n");
+        aot = 127;
+    }
+
     switch (channels) {
     case 1:
         mode = MODE_1;
@@ -50,7 +76,7 @@ hdc_encoder_impl::hdc_encoder_impl(int channels, int bitrate)
     if (aacEncOpen(&handle, 0, channels) != AACENC_OK) {
         throw std::runtime_error("hdc_encoder: Unable to open decoder");
     }
-    if (aacEncoder_SetParam(handle, AACENC_AOT, AOT_HDC) != AACENC_OK) {
+    if (aacEncoder_SetParam(handle, AACENC_AOT, aot) != AACENC_OK) {
         throw std::runtime_error("hdc_encoder: Unable to set the AOT");
     }
     if (aacEncoder_SetParam(handle, AACENC_SAMPLERATE, HDC_SAMPLE_RATE) != AACENC_OK) {
@@ -164,7 +190,12 @@ int hdc_encoder_impl::general_work(int noutput_items,
         int convert_off = 0;
         for (int i = 0; i < frame_length; i++) {
             for (int channel = 0; channel < channels; channel++) {
-                convert_buf[convert_off++] = (short)(in[channel][in_off] * 32768);
+                // Apply TX Digital Audio Gain
+                double sample = in[channel][in_off] * gain_multiplier;
+                // Clamp to prevent overflow
+                if (sample > 1.0) sample = 1.0;
+                if (sample < -1.0) sample = -1.0;
+                convert_buf[convert_off++] = (short)(sample * 32768);
             }
             in_off++;
         }
diff --git a/lib/hdc_encoder_impl.h b/lib/hdc_encoder_impl.h
index 335479b..9f69747 100644
--- a/lib/hdc_encoder_impl.h
+++ b/lib/hdc_encoder_impl.h
@@ -32,9 +32,11 @@ class hdc_encoder_impl : public hdc_encoder
     unsigned char* outbuf;
     int outbuf_off;
     int outbuf_len;
+    int tx_digital_gain;
+    double gain_multiplier;
 
 public:
-    hdc_encoder_impl(int channels, int bitrate);
+    hdc_encoder_impl(int channels, int bitrate, bool use_parametric_stereo, int tx_digital_gain);
     ~hdc_encoder_impl();
 
     // Where all the action really happens
diff --git a/lib/l1_am_encoder_impl.cc b/lib/l1_am_encoder_impl.cc
index 200140e..4b8a0fa 100644
--- a/lib/l1_am_encoder_impl.cc
+++ b/lib/l1_am_encoder_impl.cc
@@ -173,15 +173,13 @@ int l1_am_encoder_impl::general_work(int noutput_items,
                         -std::conj(qam64[pl_matrix[col][symbol]]);
                     out[out_off + 128 + 57 + col] = qam64[pu_matrix[col][symbol]];
 
-                    if (!rdb) {
-                        /* 1012s.pdf table 12-6 */
-                        out[out_off + 128 + 2 + col] = qpsk_am[t_matrix[col][symbol]];
-                        out[out_off + 128 + 28 + col] = qam16[s_matrix[col][symbol]];
-                        out[out_off + 128 - 2 - col] =
-                            -std::conj(qpsk_am[t_matrix[col][symbol]]);
-                        out[out_off + 128 - 28 - col] =
-                            -std::conj(qam16[s_matrix[col][symbol]]);
-                    }
+                    /* 1012s.pdf table 12-6 */
+                    out[out_off + 128 + 2 + col] = qpsk_am[t_matrix[col][symbol]];
+                    out[out_off + 128 + 28 + col] = qam16[s_matrix[col][symbol]];
+                    out[out_off + 128 - 2 - col] =
+                        -std::conj(qpsk_am[t_matrix[col][symbol]]);
+                    out[out_off + 128 - 28 - col] =
+                        -std::conj(qam16[s_matrix[col][symbol]]);
                     break;
                 case 3:
                     /* 1012s.pdf table 12-3 */
@@ -189,12 +187,10 @@ int l1_am_encoder_impl::general_work(int noutput_items,
                         -std::conj(qam64[pl_matrix[col][symbol]]);
                     out[out_off + 128 + 2 + col] = qam64[pu_matrix[col][symbol]];
 
-                    if (!rdb) {
-                        /* 1012s.pdf table 12-8 */
-                        out[out_off + 128 - 28 - col] =
-                            -std::conj(qam64[t_matrix[col][symbol]]);
-                        out[out_off + 128 + 28 + col] = qam64[s_matrix[col][symbol]];
-                    }
+                    /* 1012s.pdf table 12-8 */
+                    out[out_off + 128 - 28 - col] =
+                        -std::conj(qam64[t_matrix[col][symbol]]);
+                    out[out_off + 128 + 28 + col] = qam64[s_matrix[col][symbol]];
                     break;
                 }
             }
@@ -204,11 +200,9 @@ int l1_am_encoder_impl::general_work(int noutput_items,
             switch (sm) {
             case 1:
                 /* 1012s.pdf table 12-7 */
-                if (!rdb) {
-                    out[out_off + 128 - 27] = -std::conj(pids_point_0);
-                    out[out_off + 128 + 27] = pids_point_0;
-                }
+                out[out_off + 128 - 27] = -std::conj(pids_point_0);
                 out[out_off + 128 - 53] = -std::conj(pids_point_1);
+                out[out_off + 128 + 27] = pids_point_0;
                 out[out_off + 128 + 53] = pids_point_1;
                 break;
             case 3:
@@ -336,10 +330,8 @@ void l1_am_encoder_impl::interleaver_ma1()
 {
     memset(pu_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
     memset(pl_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
-    if (!rdb) {
-        memset(s_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
-        memset(t_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
-    }
+    memset(s_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
+    memset(t_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
 
     for (int i = 0; i < 6000; i++) {
         for (int j = 0; j < 3; j++) {
@@ -348,13 +340,11 @@ void l1_am_encoder_impl::interleaver_ma1()
             bu[DIVERSITY_DELAY + i * 3 + j] = p1_g[i * 12 + bu_delay[j]];
             mu[i * 3 + j] = p1_g[i * 12 + mu_delay[j]];
         }
-        if (!rdb) {
-            for (int j = 0; j < 2; j++) {
-                el[i * 2 + j] = p3_g[i * 6 + el_delay[j]];
-            }
-            for (int j = 0; j < 4; j++) {
-                eu[i * 4 + j] = p3_g[i * 6 + eu_delay[j]];
-            }
+        for (int j = 0; j < 2; j++) {
+            el[i * 2 + j] = p3_g[i * 6 + el_delay[j]];
+        }
+        for (int j = 0; j < 4; j++) {
+            eu[i * 4 + j] = p3_g[i * 6 + eu_delay[j]];
         }
     }
 
@@ -380,19 +370,17 @@ void l1_am_encoder_impl::interleaver_ma1()
         p = 3 + (n % 3);
         bit_map(pu_matrix, b, k, mu[n] << p);
     }
-    if (!rdb) {
-        for (int n = 0; n < 12000; n++) {
-            b = (3 * n + n / 3000) % 8;
-            k = (n + (n / 6000)) % 750;
-            p = n % 2;
-            bit_map(t_matrix, b, k, el[n] << p);
-        }
-        for (int n = 0; n < 24000; n++) {
-            b = (3 * n + n / 3000 + 2 * (n / 12000)) % 8;
-            k = (n + (n / 6000)) % 750;
-            p = n % 4;
-            bit_map(s_matrix, b, k, eu[n] << p);
-        }
+    for (int n = 0; n < 12000; n++) {
+        b = (3 * n + n / 3000) % 8;
+        k = (n + (n / 6000)) % 750;
+        p = n % 2;
+        bit_map(t_matrix, b, k, el[n] << p);
+    }
+    for (int n = 0; n < 24000; n++) {
+        b = (3 * n + n / 3000 + 2 * (n / 12000)) % 8;
+        k = (n + (n / 6000)) % 750;
+        p = n % 4;
+        bit_map(s_matrix, b, k, eu[n] << p);
     }
 
     /* training symbols */
@@ -400,10 +388,8 @@ void l1_am_encoder_impl::interleaver_ma1()
         for (int k = 750; k < 800; k++) {
             bit_map(pu_matrix, block, k, 0b100101);
             bit_map(pl_matrix, block, k, 0b100101);
-            if (!rdb) {
-                bit_map(s_matrix, block, k, 0b1001);
-                bit_map(t_matrix, block, k, 0b10);
-            }
+            bit_map(s_matrix, block, k, 0b1001);
+            bit_map(t_matrix, block, k, 0b10);
         }
     }
 
@@ -415,10 +401,8 @@ void l1_am_encoder_impl::interleaver_ma3()
 {
     memset(pu_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
     memset(pl_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
-    if (!rdb) {
-        memset(s_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
-        memset(t_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
-    }
+    memset(s_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
+    memset(t_matrix, 0, 25 * AM_SYMBOLS_PER_FRAME);
 
     for (int i = 0; i < 6000; i++) {
         for (int j = 0; j < 3; j++) {
@@ -427,12 +411,10 @@ void l1_am_encoder_impl::interleaver_ma3()
             bu[DIVERSITY_DELAY + i * 3 + j] = p1_g[i * 12 + bu_delay[j]];
             mu[i * 3 + j] = p1_g[i * 12 + mu_delay[j]];
 
-            if (!rdb) {
-                ebl[DIVERSITY_DELAY + i * 3 + j] = p3_g[i * 12 + bl_delay[j]];
-                eml[i * 3 + j] = p3_g[i * 12 + ml_delay[j]];
-                ebu[DIVERSITY_DELAY + i * 3 + j] = p3_g[i * 12 + bu_delay[j]];
-                emu[i * 3 + j] = p3_g[i * 12 + mu_delay[j]];
-            }
+            ebl[DIVERSITY_DELAY + i * 3 + j] = p3_g[i * 12 + bl_delay[j]];
+            eml[i * 3 + j] = p3_g[i * 12 + ml_delay[j]];
+            ebu[DIVERSITY_DELAY + i * 3 + j] = p3_g[i * 12 + bu_delay[j]];
+            emu[i * 3 + j] = p3_g[i * 12 + mu_delay[j]];
         }
     }
 
@@ -458,27 +440,25 @@ void l1_am_encoder_impl::interleaver_ma3()
         p = 3 + (n % 3);
         bit_map(pu_matrix, b, k, mu[n] << p);
 
-        if (!rdb) {
-            b = (3 * n + 3) % 8;
-            k = (n + n / 3000 + 3) % 750;
-            p = n % 3;
-            bit_map(t_matrix, b, k, ebl[n] << p);
-
-            b = (3 * n + 3) % 8;
-            k = (n + n / 3000 + 3) % 750;
-            p = 3 + (n % 3);
-            bit_map(t_matrix, b, k, eml[n] << p);
-
-            b = (3 * n) % 8;
-            k = (n + n / 3000 + 2) % 750;
-            p = n % 3;
-            bit_map(s_matrix, b, k, ebu[n] << p);
-
-            b = (3 * n) % 8;
-            k = (n + n / 3000 + 2) % 750;
-            p = 3 + (n % 3);
-            bit_map(s_matrix, b, k, emu[n] << p);
-        }
+        b = (3 * n + 3) % 8;
+        k = (n + n / 3000 + 3) % 750;
+        p = n % 3;
+        bit_map(t_matrix, b, k, ebl[n] << p);
+
+        b = (3 * n + 3) % 8;
+        k = (n + n / 3000 + 3) % 750;
+        p = 3 + (n % 3);
+        bit_map(t_matrix, b, k, eml[n] << p);
+
+        b = (3 * n) % 8;
+        k = (n + n / 3000 + 2) % 750;
+        p = n % 3;
+        bit_map(s_matrix, b, k, ebu[n] << p);
+
+        b = (3 * n) % 8;
+        k = (n + n / 3000 + 2) % 750;
+        p = 3 + (n % 3);
+        bit_map(s_matrix, b, k, emu[n] << p);
     }
 
     /* training symbols */
@@ -486,19 +466,15 @@ void l1_am_encoder_impl::interleaver_ma3()
         for (int k = 750; k < 800; k++) {
             bit_map(pu_matrix, block, k, 0b100101);
             bit_map(pl_matrix, block, k, 0b100101);
-            if (!rdb) {
-                bit_map(s_matrix, block, k, 0b100101);
-                bit_map(t_matrix, block, k, 0b100101);
-            }
+            bit_map(s_matrix, block, k, 0b100101);
+            bit_map(t_matrix, block, k, 0b100101);
         }
     }
 
     memmove(bl, bl + 18000, DIVERSITY_DELAY);
     memmove(bu, bu + 18000, DIVERSITY_DELAY);
-    if (!rdb) {
-        memmove(ebl, ebl + 18000, DIVERSITY_DELAY);
-        memmove(ebu, ebu + 18000, DIVERSITY_DELAY);
-    }
+    memmove(ebl, ebl + 18000, DIVERSITY_DELAY);
+    memmove(ebu, ebu + 18000, DIVERSITY_DELAY);
 }
 
 void l1_am_encoder_impl::interleaver_pids(unsigned char* in,
@@ -540,7 +516,7 @@ void l1_am_encoder_impl::interleaver_pids(unsigned char* in,
 
 /* 1012s.pdf table 11-1 */
 void l1_am_encoder_impl::sc_data_seq(
-    unsigned char* out, int pli, int hppi, int aabi, int rdbi, int bc, int smi)
+    unsigned char* out, int pli, int hppi, int abbi, int rdbi, int bc, int smi)
 {
     out[0] = 0; // sync
     out[1] = 1; // sync
@@ -557,7 +533,7 @@ void l1_am_encoder_impl::sc_data_seq(
 
     out[10] = 0;                           // reserved
     out[11] = hppi;                        // high power pids indicator
-    out[12] = aabi;                        // analog audio bandwidth indicator
+    out[12] = abbi;                        // analog audio bandwidth indicator
     out[13] = out[10] ^ out[11] ^ out[12]; // parity
 
     out[14] = 0; // sync
@@ -592,77 +568,42 @@ void l1_am_encoder_impl::set_channel_power()
 
     // Table 4-6 from 1082s.pdf
     switch (sm) {
-    case 1: {
-        float db_pu = -30;
-        float db_pl = -30;
-        float db_s = (pl ? -37 : -43);
-        float db_t[25];
-        float db_ref = -26;
-        float db_pids1 = (pl ? -37 : -43);
-        float db_pids2_diff;
-
-        for (int col = 0; col < 25; col++) {
-            if (pl) {
-                db_t[col] = -44;
-            } else {
-                if (col < 12) {
-                    db_t[col] = -44 - (0.5 * col);
-                } else {
-                    db_t[col] = -50;
-                }
-            }
-        }
-
-        if (rdb || hpp) {
-            db_pids2_diff = 0;
-        } else if (pl) {
-            db_pids2_diff = -7;
-        } else {
-            db_pids2_diff = -13;
-        }
-
+    case 1:
         for (int col = 0; col < 25; col++) {
-            channel_power[128 + 57 + col] = db_pu - qam64_power;
-            channel_power[128 - 57 - col] = db_pl - qam64_power;
+            channel_power[128 + 57 + col] = -30 - qam64_power;
+            channel_power[128 - 57 - col] = -30 - qam64_power;
 
-            channel_power[128 + 28 + col] = db_s - qam16_power;
-            channel_power[128 - 28 - col] = db_s - qam16_power;
+            channel_power[128 + 28 + col] = -43 - qam16_power;
+            channel_power[128 - 28 - col] = -43 - qam16_power;
 
-            channel_power[128 + 2 + col] = db_t[col] - qpsk_power;
-            channel_power[128 - 2 - col] = db_t[col] - qpsk_power;
+            channel_power[128 + 2 + col] = (col < 12 ? (-44 - 0.5 * col) : -50) - qpsk_power;
+            channel_power[128 - 2 - col] = (col < 12 ? (-44 - 0.5 * col) : -50) - qpsk_power;
         }
 
-        channel_power[128 + 1] = db_ref - bpsk_power;
-        channel_power[128 - 1] = db_ref - bpsk_power;
+        channel_power[128 + 1] = -26 - bpsk_power;
+        channel_power[128 - 1] = -26 - bpsk_power;
 
-        channel_power[128 + 27] = db_pids1 - qam16_power;
-        channel_power[128 - 27] = db_pids1 - qam16_power;
-        channel_power[128 + 53] = db_pu + db_pids2_diff - qam16_power;
-        channel_power[128 - 53] = db_pl + db_pids2_diff - qam16_power;
+        channel_power[128 + 27] = -43 - qam16_power;
+        channel_power[128 - 27] = -43 - qam16_power;
+        channel_power[128 + 53] = -43 - qam16_power;
+        channel_power[128 - 53] = -43 - qam16_power;
         break;
-    }
-    case 3: {
-        float db_p = -15;
-        float db_e = -30;
-        float db_ref = -15;
-        float db_pids_diff = ((rdb || hpp) ? 0 : -15);
-
+    case 3:
         for (int col = 0; col < 25; col++) {
-            channel_power[128 + 2 + col] = db_p - qam64_power;
-            channel_power[128 - 2 - col] = db_p - qam64_power;
+            channel_power[128 + 2 + col] = -15 - qam64_power;
+            channel_power[128 - 2 - col] = -15 - qam64_power;
 
-            channel_power[128 + 28 + col] = db_e - qam64_power;
-            channel_power[128 - 28 - col] = db_e - qam64_power;
+            channel_power[128 + 28 + col] = -30 - qam64_power;
+            channel_power[128 - 28 - col] = -30 - qam64_power;
         }
 
-        channel_power[128 + 1] = db_ref - bpsk_power;
-        channel_power[128 - 1] = db_ref - bpsk_power;
+        channel_power[128 + 1] = -15 - bpsk_power;
+        channel_power[128 - 1] = -15 - bpsk_power;
 
-        channel_power[128 + 27] = db_p + db_pids_diff - qam16_power;
-        channel_power[128 - 27] = db_p + db_pids_diff - qam16_power;
+        channel_power[128 + 27] = -30 - qam16_power;
+        channel_power[128 - 27] = -30 - qam16_power;
         break;
     }
-    }
 
     for (int i = 0; i < AM_FFT_SIZE; i++) {
         channel_power[i] = pow(10, channel_power[i] / 20);
diff --git a/lib/l1_fm_encoder_impl.cc b/lib/l1_fm_encoder_impl.cc
index 6544530..f11035a 100644
--- a/lib/l1_fm_encoder_impl.cc
+++ b/lib/l1_fm_encoder_impl.cc
@@ -15,7 +15,7 @@
 namespace gr {
 namespace nrsc5 {
 
-std::vector<int> get_in_sizeofs_fm(const int psm, const int ssm)
+std::vector<int> get_in_sizeofs(const int psm, const int ssm)
 {
     std::vector<int> in_sizeofs;
 
@@ -67,7 +67,7 @@ l1_fm_encoder::sptr l1_fm_encoder::make(const int psm, const int ssm)
  */
 l1_fm_encoder_impl::l1_fm_encoder_impl(const int psm, const int ssm)
     : gr::block("l1_fm_encoder",
-                gr::io_signature::makev(2, 9, get_in_sizeofs_fm(psm, ssm)),
+                gr::io_signature::makev(2, 9, get_in_sizeofs(psm, ssm)),
                 gr::io_signature::make(1, 1, sizeof(gr_complex) * FM_FFT_SIZE))
 {
     set_output_multiple(FM_SYMBOLS_PER_FRAME);
@@ -336,6 +336,11 @@ int l1_fm_encoder_impl::general_work(int noutput_items,
                     px2_matrix + (symbol * 8 * 36), out + out_off, px2_channels, 8);
             }
 
+            // Explicitly suppress DC bin (bin 0) to eliminate carrier spike
+            // Also suppress Nyquist bin (1024) for proper conjugate symmetry
+            out[out_off + 0] = gr_complex(0, 0);
+            out[out_off + 1024] = gr_complex(0, 0);
+
             out_off += FM_FFT_SIZE;
         }
         message_port_pub(pmt::intern("clock"), pmt::from_long(1));
@@ -550,7 +555,7 @@ void l1_fm_encoder_impl::primary_sc_data_seq(
 
     out[10] = (scid & 0x2) >> 1;
     out[11] = (scid & 0x1);
-    out[12] = 0;                           // ASM1
+    out[12] = 0; // ASM1
     out[13] = out[10] ^ out[11] ^ out[12]; // parity
 
     out[14] = 0; // sync
diff --git a/lib/l2_encoder_impl.cc b/lib/l2_encoder_impl.cc
index b8d84f2..3602dce 100644
--- a/lib/l2_encoder_impl.cc
+++ b/lib/l2_encoder_impl.cc
@@ -27,10 +27,12 @@ l2_encoder::sptr l2_encoder::make(const int num_progs,
                                   const int size,
                                   const int data_bytes,
                                   const blend blend_control,
+                                  const int tx_digital_gain,
+                                  const bool debug_logs,
                                   const int ccc_width)
 {
     return gnuradio::get_initial_sptr(
-        new l2_encoder_impl(num_progs, first_prog, size, data_bytes, blend_control, ccc_width));
+        new l2_encoder_impl(num_progs, first_prog, size, data_bytes, blend_control, tx_digital_gain, debug_logs, ccc_width));
 }
 
 
@@ -42,6 +44,8 @@ l2_encoder_impl::l2_encoder_impl(const int num_progs,
                                  const int size,
                                  const int data_bytes,
                                  const blend blend_control,
+                                 const int tx_digital_gain,
+                                 const bool debug_logs,
                                  const int ccc_width)
     : gr::block("l2_encoder",
                 gr::io_signature::make(0, 16, sizeof(unsigned char)),
@@ -59,6 +63,18 @@ l2_encoder_impl::l2_encoder_impl(const int num_progs,
     this->size = size;
     this->data_bytes = data_bytes;
     this->blend_control = blend_control;
+    this->debug_logs = debug_logs;
+
+    // Validate and clamp TX Digital Audio Gain to valid range (-8 to +6 dB)
+    if (tx_digital_gain < -8) {
+        this->tx_digital_gain = -8;
+        fprintf(stderr, "Warning: TX Digital Audio Gain clamped to minimum -8 dB\n");
+    } else if (tx_digital_gain > 6) {
+        this->tx_digital_gain = 6;
+        fprintf(stderr, "Warning: TX Digital Audio Gain clamped to maximum +6 dB\n");
+    } else {
+        this->tx_digital_gain = tx_digital_gain;
+    }
     payload_bytes = (size - 22) / 8;
     out_buf = (unsigned char*)malloc(payload_bytes);
     rs_enc = init_rs_char(8, 0x11d, 1, 1, 8);
@@ -142,6 +158,7 @@ int l2_encoder_impl::general_work(int noutput_items,
         for (int p = 0; p < num_progs; p++) {
             int program_number = first_prog + p;
             int bytes_left = (out_buf + payload_bytes - total_data_width) - out_program;
+            int bytes_left_at_start = bytes_left;  // Save for error reporting
             int nop = 0;
             int off = hdc_off[p];
             int audio_length = 0;
@@ -189,7 +206,7 @@ int l2_encoder_impl::general_work(int noutput_items,
                                /*stream_id*/ 0,
                                pdu_seq_no,
                                program_number == 0 ? static_cast<int>(blend_control) : 0,
-                               /*digital_gain_or_per_stream_delay*/ 0,
+                               /*digital_gain_or_per_stream_delay*/ tx_gain_db_to_value(tx_digital_gain),
                                /*common_delay*/ program_number == 0 ? 24 : 0,
                                /*latency*/ 4,
                                partial_bytes[p] ? 1 : 0,
@@ -247,7 +264,119 @@ int l2_encoder_impl::general_work(int noutput_items,
             out_program += (end + 1);
 
             if (target_seq_no - start_seq_no[p] > 8) {
-                fprintf(stderr, "Audio bitrate it too high\n");
+                // Calculate approximate bitrate based on ADTS frame sizes
+                int frames_behind = target_seq_no - start_seq_no[p];
+
+                // Use the space that was available at the START of processing this program
+                int bytes_available_for_program = bytes_left_at_start;
+
+                // Determine service mode based on size parameter
+                const char* service_mode;
+                int max_bitrate_kbps;
+                switch (size) {
+                    case 146176:
+                        service_mode = "MP1 (Primary)";
+                        max_bitrate_kbps = 96;
+                        break;
+                    case 109312:
+                        service_mode = "MP5 (Hybrid)";
+                        max_bitrate_kbps = 72;
+                        break;
+                    case 72448:
+                        service_mode = "MP6 (Hybrid)";
+                        max_bitrate_kbps = 48;
+                        break;
+                    case 30000:
+                    case 24000:
+                        service_mode = "MP1 (Low bitrate)";
+                        max_bitrate_kbps = 32;
+                        break;
+                    case 9216:
+                        service_mode = "MP6 (Data)";
+                        max_bitrate_kbps = 24;
+                        break;
+                    case 4608:
+                        service_mode = "MP3 (Data)";
+                        max_bitrate_kbps = 12;
+                        break;
+                    case 3750:
+                        service_mode = "MP5 (Data)";
+                        max_bitrate_kbps = 10;
+                        break;
+                    case 2304:
+                        service_mode = "MP2 (Data)";
+                        max_bitrate_kbps = 6;
+                        break;
+                    default:
+                        service_mode = "Unknown";
+                        max_bitrate_kbps = 0;
+                }
+
+                fprintf(stderr,
+                    "\n"
+                    "================================================================================\n"
+                    "ERROR: Audio bitrate is too high\n"
+                    "================================================================================\n"
+                    "Location:     l2_encoder_impl.cc:general_work() - Program %d (index %d/%d)\n"
+                    "Service Mode: %s (PDU size: %d bits)\n"
+                    "Problem:      Encoder is %d frames behind (threshold: 8)\n"
+                    "              The audio encoder is producing more data than the HD Radio\n"
+                    "              channel can transmit.\n"
+                    "\n"
+                    "PDU Space Analysis:\n"
+                    "  Total payload:           %d bytes\n"
+                    "  Data subchannel:         %d bytes (fixed data + config control)\n"
+                    "  PSD bytes per program:   %d bytes\n"
+                    "  Space for all programs:  %d bytes\n"
+                    "  Available for Program %d: %d bytes (before processing)\n"
+                    "  Programs in this PDU:    %d (numbered %d-%d)\n"
+                    "\n"
+                    "Maximum recommended audio bitrate: %d kbps\n"
+                    "\n"
+                    "How to fix in GRC file:\n"
+                    "  OPTION 1 - Reduce Audio Bitrate:\n"
+                    "    1. Locate the 'HDC Encoder' block for Program %d\n"
+                    "    2. Reduce the 'Bitrate' parameter to %d kbps or lower\n"
+                    "    3. Common safe values: 32, 48, 64, or 96 kbps (depending on mode)\n"
+                    "\n",
+                    program_number, p + 1, num_progs, service_mode, size, frames_behind,
+                    payload_bytes, total_data_width, psd_bytes,
+                    payload_bytes - total_data_width, program_number,
+                    bytes_available_for_program, num_progs, first_prog,
+                    first_prog + num_progs - 1, max_bitrate_kbps,
+                    program_number, max_bitrate_kbps);
+
+                if (data_bytes > 0) {
+                    fprintf(stderr,
+                        "  OPTION 2 - Reduce Fixed Data Bandwidth:\n"
+                        "    1. Locate the 'L2 Encoder' block\n"
+                        "    2. Current 'Data Bytes' parameter: %d bytes/frame\n"
+                        "    3. Reduce 'Data Bytes' to free up space for audio\n"
+                        "    4. Each byte freed = ~%d bps more audio capacity\n"
+                        "\n",
+                        data_bytes, (int)(data_bytes * 8.0 * 1000 / (size / 8.0)));
+                }
+
+                if (psd_bytes > 8) {
+                    fprintf(stderr,
+                        "  OPTION 3 - Reduce PSD Size (if excessive):\n"
+                        "    1. Current PSD: %d bytes/frame per program\n"
+                        "    2. Check if you're sending excessive metadata\n"
+                        "    3. Standard PSD for data modes: 8 bytes is typical\n"
+                        "\n",
+                        psd_bytes);
+                }
+
+                fprintf(stderr,
+                    "  OPTION 4 - Use Fewer Programs:\n"
+                    "    Current: %d program(s) sharing %d bytes\n"
+                    "    Reducing program count increases space per program\n"
+                    "\n"
+                    "Note: Lower bitrates may reduce audio quality but are necessary for\n"
+                    "      reliable transmission. Balance audio quality, data services, and\n"
+                    "      number of programs based on your service mode's capacity.\n"
+                    "================================================================================\n",
+                    num_progs, payload_bytes - total_data_width);
             }
         }
 
@@ -290,6 +419,7 @@ int l2_encoder_impl::general_work(int noutput_items,
                 }
             }
 
+            int data_bytes_this_frame = 0;
             for (int i = payload_bytes - 1 - ccc_width - data_bytes;
                  i < payload_bytes - 1 - ccc_width;
                  i++) {
@@ -299,6 +429,7 @@ int l2_encoder_impl::general_work(int noutput_items,
                     if (aas_queue_bytes == 0) { // all queues are empty
                         out_buf[i] = 0x7e;
                     } else { // at least one queue still has data
+                        data_bytes_this_frame++;
                         // advance to the next non-empty queue if necessary
                         while (aas_queues[aas_current_port].empty()) {
                             aas_current_port_index =
@@ -315,18 +446,37 @@ int l2_encoder_impl::general_work(int noutput_items,
                         if (out_buf[i] == 0x7e) {
                             // if we emptied the queue, ask for more
                             if (aas_queues[aas_current_port].empty()) {
+                                if (debug_logs) {
+                                    fprintf(stderr, "L2: Port %d queue empty, sending ready signal and switching ports\n", aas_current_port);
+                                }
                                 message_port_pub(pmt::intern("ready"),
                                                  pmt::from_long(aas_current_port));
-                            }
 
-                            aas_current_port_index =
-                                (aas_current_port_index + 1) % aas_ports.size();
-                            aas_current_port = aas_ports[aas_current_port_index];
+                                // Switch to next port immediately if queue is empty
+                                aas_current_port_index =
+                                    (aas_current_port_index + 1) % aas_ports.size();
+                                aas_current_port = aas_ports[aas_current_port_index];
+                            } else {
+                                // Keep sending from the same port if queue still has data
+                                // This allows bursts of multiple PDUs from same port for faster transmission
+                                if (debug_logs) {
+                                    fprintf(stderr, "L2: Port %d still has data (%zu bytes), continuing burst\n",
+                                            aas_current_port, aas_queues[aas_current_port].size());
+                                }
+                            }
                         }
                     }
                 }
                 aas_block_offset = (aas_block_offset + 1) % (255 + 4);
             }
+
+            if (debug_logs) {
+                static int frame_counter = 0;
+                if (++frame_counter % 100 == 0) {
+                    fprintf(stderr, "L2: Transmitted %d data bytes this frame (data_bytes param=%d, overhead=%d)\n",
+                            data_bytes_this_frame, data_bytes, data_bytes - data_bytes_this_frame);
+                }
+            }
         }
 
         const unsigned char *pci;
@@ -466,6 +616,27 @@ int l2_encoder_impl::adts_length(const unsigned char* header)
 
 int l2_encoder_impl::len_locators(int nop) { return ((lc_bits * nop) + 4) / 8; }
 
+/* Convert TX Digital Audio Gain from dB to 5-bit value per NRSC-5 spec Table 5-5 */
+int l2_encoder_impl::tx_gain_db_to_value(int gain_db)
+{
+    // Table 5-5: TX Digital Audio Gain Control
+    // Value range: 0b11000 (-8 dB) to 0b00110 (+6 dB)
+    // 0b00000 = 0 dB (center value)
+    // Negative gains: 0b11000 to 0b11111 (-8 to -1 dB)
+    // Positive gains: 0b00001 to 0b00110 (+1 to +6 dB)
+
+    if (gain_db >= -8 && gain_db < 0) {
+        // Negative gain: map -8..-1 dB to 0b11000..0b11111 (24..31)
+        return 24 + (gain_db + 8);
+    } else if (gain_db >= 0 && gain_db <= 6) {
+        // Zero or positive gain: map 0..+6 dB to 0b00000..0b00110 (0..6)
+        return gain_db;
+    } else {
+        // Invalid value (should not happen due to validation in constructor)
+        return 0; // Default to 0 dB
+    }
+}
+
 void l2_encoder_impl::handle_aas_pdu(pmt::pmt_t msg)
 {
     std::vector<unsigned char> pdu_bytes = pmt::u8vector_elements(pmt::cdr(msg));
diff --git a/lib/l2_encoder_impl.h b/lib/l2_encoder_impl.h
index a014946..e6cae7b 100644
--- a/lib/l2_encoder_impl.h
+++ b/lib/l2_encoder_impl.h
@@ -67,6 +67,8 @@ class l2_encoder_impl : public l2_encoder
     int size;
     int data_bytes;
     blend blend_control;
+    int tx_digital_gain;
+    bool debug_logs;
     int payload_bytes;
     unsigned char rs_buf[255];
     void* rs_enc;
@@ -110,6 +112,7 @@ class l2_encoder_impl : public l2_encoder
     header_spread(const unsigned char* in, unsigned char* out, const unsigned char* pci);
     int adts_length(const unsigned char* header);
     int len_locators(int nop);
+    int tx_gain_db_to_value(int gain_db);
     void handle_aas_pdu(pmt::pmt_t msg);
     void decode_sig(std::vector<unsigned char>& pdu_bytes);
 
@@ -119,6 +122,8 @@ class l2_encoder_impl : public l2_encoder
                     const int size,
                     const int data_bytes = 0,
                     const blend blend_control = blend::ENABLE,
+                    const int tx_digital_gain = 0,
+                    const bool debug_logs = false,
                     const int ccc_width = 24);
     ~l2_encoder_impl();
 
diff --git a/lib/psd_encoder_impl.cc b/lib/psd_encoder_impl.cc
index 677259c..1bf9999 100644
--- a/lib/psd_encoder_impl.cc
+++ b/lib/psd_encoder_impl.cc
@@ -20,10 +20,16 @@ namespace nrsc5 {
 psd_encoder::sptr psd_encoder::make(const int prog_num,
                                     const std::string& title,
                                     const std::string& artist,
+                                    const std::string& album,
+                                    const std::string& genre,
+                                    const std::string& comment_language,
+                                    const std::string& comment_short_desc,
+                                    const std::string& comment_text,
                                     const int bytes_per_frame)
 {
     return gnuradio::get_initial_sptr(
-        new psd_encoder_impl(prog_num, title, artist, bytes_per_frame));
+        new psd_encoder_impl(prog_num, title, artist, album, genre,
+                           comment_language, comment_short_desc, comment_text, bytes_per_frame));
 }
 
 
@@ -33,6 +39,11 @@ psd_encoder::sptr psd_encoder::make(const int prog_num,
 psd_encoder_impl::psd_encoder_impl(const int prog_num,
                                    const std::string& title,
                                    const std::string& artist,
+                                   const std::string& album,
+                                   const std::string& genre,
+                                   const std::string& comment_language,
+                                   const std::string& comment_short_desc,
+                                   const std::string& comment_text,
                                    const int bytes_per_frame)
     : gr::sync_block("psd_encoder",
                      gr::io_signature::make(0, 0, 0),
@@ -41,6 +52,19 @@ psd_encoder_impl::psd_encoder_impl(const int prog_num,
     this->prog_num = prog_num;
     this->title = title;
     this->artist = artist;
+    this->album = album;
+    this->genre = genre;
+    this->comment_language = comment_language;
+    this->comment_short_desc = comment_short_desc;
+    this->comment_text = comment_text;
+    this->commercial_price = "";
+    this->commercial_valid_until = "";
+    this->commercial_contact_url = "";
+    this->commercial_received_as = "";
+    this->commercial_seller = "";
+    this->commercial_description = "";
+    this->ufid_owner = "";
+    this->ufid_identifier = "";
     this->bytes_per_frame = bytes_per_frame;
     lot = -1;
     seq_num = 0;
@@ -111,8 +135,48 @@ std::string psd_encoder_impl::encode_id3()
 {
     std::stringstream out;
 
-    std::string payload = encode_text_frame("TIT2", title) +
-                          encode_text_frame("TPE1", artist) + encode_xhdr_frame();
+    std::string payload = "";
+
+    // PSD Type 1: Title (TIT2) - Required
+    if (!title.empty()) {
+        payload += encode_text_frame("TIT2", title);
+    }
+
+    // PSD Type 2: Artist (TPE1) - Required
+    if (!artist.empty()) {
+        payload += encode_text_frame("TPE1", artist);
+    }
+
+    // PSD Type 3: Album (TALB)
+    if (!album.empty()) {
+        payload += encode_text_frame("TALB", album);
+    }
+
+    // PSD Type 4: Genre (TCON)
+    if (!genre.empty()) {
+        payload += encode_text_frame("TCON", genre);
+    }
+
+    // PSD Type 5: Comment (COMM)
+    if (!comment_text.empty() || !comment_short_desc.empty()) {
+        payload += encode_comment_frame(comment_language, comment_short_desc, comment_text);
+    }
+
+    // PSD Type 6: Commercial (COMR)
+    if (!commercial_description.empty() || !commercial_contact_url.empty()) {
+        payload += encode_commercial_frame(commercial_price, commercial_valid_until,
+                                          commercial_contact_url, commercial_received_as,
+                                          commercial_seller, commercial_description);
+    }
+
+    // PSD Type 7: Reference Identifier (UFID)
+    if (!ufid_owner.empty() && !ufid_identifier.empty()) {
+        payload += encode_ufid_frame(ufid_owner, ufid_identifier);
+    }
+
+    // XHDR frame for album art
+    payload += encode_xhdr_frame();
+
     int len = payload.length();
 
     out << "ID3";
@@ -148,6 +212,129 @@ std::string psd_encoder_impl::encode_text_frame(const std::string& id,
     return out.str();
 }
 
+std::string psd_encoder_impl::encode_comment_frame(const std::string& language,
+                                                    const std::string& short_desc,
+                                                    const std::string& text)
+{
+    std::stringstream out;
+
+    // COMM frame structure:
+    // Text encoding: 1 byte (0x00 for ISO-8859-1, 0x01 for Unicode)
+    // Language: 3 bytes (ISO 639-2)
+    // Short description: null-terminated string
+    // Content: text string (not null-terminated)
+
+    std::string lang = language.empty() ? "eng" : language;
+    if (lang.length() > 3) {
+        lang = lang.substr(0, 3);
+    }
+    while (lang.length() < 3) {
+        lang += " ";
+    }
+
+    int len = 1 + 3 + short_desc.length() + 1 + text.length();
+
+    out << "COMM";
+    out << (char)((len >> 24) & 0xff);
+    out << (char)((len >> 16) & 0xff);
+    out << (char)((len >> 8) & 0xff);
+    out << (char)(len & 0xff);
+    out << (char)0;  // Flags byte 1
+    out << (char)0;  // Flags byte 2
+    out << (char)0;  // Text encoding (ISO-8859-1)
+    out << lang;     // 3-byte language code
+    out << short_desc;
+    out << (char)0;  // Null terminator for short description
+    out << text;
+
+    return out.str();
+}
+
+std::string psd_encoder_impl::encode_commercial_frame(const std::string& price,
+                                                       const std::string& valid_until,
+                                                       const std::string& contact_url,
+                                                       const std::string& received_as,
+                                                       const std::string& seller,
+                                                       const std::string& description)
+{
+    std::stringstream out;
+
+    // COMR frame structure:
+    // Text encoding: 1 byte (0x00 for ISO-8859-1)
+    // Price: null-terminated string
+    // Valid until: 8 bytes (YYYYMMDD format as string)
+    // Contact URL: null-terminated string
+    // Received as: 1 byte
+    // Seller name: null-terminated string
+    // Description: null-terminated string
+    // Picture MIME type: null-terminated string (empty for PSD - binary pictures not supported)
+    // Seller logo: null-terminated string (empty for PSD - binary pictures not supported)
+
+    int len = 1 + price.length() + 1 + 8 + contact_url.length() + 1 + 1 +
+              seller.length() + 1 + description.length() + 1 + 1 + 1;
+
+    out << "COMR";
+    out << (char)((len >> 24) & 0xff);
+    out << (char)((len >> 16) & 0xff);
+    out << (char)((len >> 8) & 0xff);
+    out << (char)(len & 0xff);
+    out << (char)0;  // Flags byte 1
+    out << (char)0;  // Flags byte 2
+    out << (char)0;  // Text encoding (ISO-8859-1)
+    out << price;
+    out << (char)0;  // Null terminator for price
+
+    // Valid until date (8 bytes, pad with spaces if needed)
+    std::string valid = valid_until;
+    if (valid.length() > 8) {
+        valid = valid.substr(0, 8);
+    }
+    while (valid.length() < 8) {
+        valid += " ";
+    }
+    out << valid;
+
+    out << contact_url;
+    out << (char)0;  // Null terminator for contact URL
+
+    // Received as (1 byte - typically 0x00)
+    out << (char)(received_as.empty() ? 0 : received_as[0]);
+
+    out << seller;
+    out << (char)0;  // Null terminator for seller name
+    out << description;
+    out << (char)0;  // Null terminator for description
+    out << (char)0;  // Empty picture MIME type (not supported)
+    out << (char)0;  // Empty seller logo (not supported)
+
+    return out.str();
+}
+
+std::string psd_encoder_impl::encode_ufid_frame(const std::string& owner,
+                                                 const std::string& identifier)
+{
+    std::stringstream out;
+
+    // UFID frame structure:
+    // Owner identifier: null-terminated string (typically a URL)
+    // Identifier: binary or text data (up to 64 bytes)
+
+    int len = owner.length() + 1 + identifier.length();
+
+    out << "UFID";
+    out << (char)((len >> 24) & 0xff);
+    out << (char)((len >> 16) & 0xff);
+    out << (char)((len >> 8) & 0xff);
+    out << (char)(len & 0xff);
+    out << (char)0;  // Flags byte 1
+    out << (char)0;  // Flags byte 2
+    out << owner;
+    out << (char)0;  // Null terminator for owner
+    out << identifier;
+
+    return out.str();
+}
+
 std::string psd_encoder_impl::encode_xhdr_frame()
 {
     std::stringstream out;
@@ -196,13 +383,70 @@ void psd_encoder_impl::set_meta(const pmt::pmt_t& msg)
             std::string line = meta_buffer.str();
             meta_buffer.str("");
 
+            // PSD Type 1: Title (TIT2)
             if (line.rfind("title", 0) == 0) {
-                title = line.substr(5, msg_len - 5);
-            } else if (line.rfind("artist", 0) == 0) {
-                artist = line.substr(6, msg_len - 6);
-            } else if (line.rfind("lot", 0) == 0) {
+                title = line.substr(5);
+            }
+            // PSD Type 2: Artist (TPE1)
+            else if (line.rfind("artist", 0) == 0) {
+                artist = line.substr(6);
+            }
+            // PSD Type 3: Album (TALB)
+            else if (line.rfind("album", 0) == 0) {
+                album = line.substr(5);
+            }
+            // PSD Type 4: Genre (TCON)
+            else if (line.rfind("genre", 0) == 0) {
+                genre = line.substr(5);
+            }
+            // PSD Type 5: Comment (COMM) - Language
+            else if (line.rfind("comment_language", 0) == 0) {
+                comment_language = line.substr(16);
+            }
+            // PSD Type 5: Comment (COMM) - Short description
+            else if (line.rfind("comment_short", 0) == 0) {
+                comment_short_desc = line.substr(13);
+            }
+            // PSD Type 5: Comment (COMM) - Content/text
+            else if (line.rfind("comment", 0) == 0) {
+                comment_text = line.substr(7);
+            }
+            // PSD Type 6: Commercial (COMR) - Price
+            else if (line.rfind("commercial_price", 0) == 0) {
+                commercial_price = line.substr(16);
+            }
+            // PSD Type 6: Commercial (COMR) - Valid until
+            else if (line.rfind("commercial_valid", 0) == 0) {
+                commercial_valid_until = line.substr(16);
+            }
+            // PSD Type 6: Commercial (COMR) - Contact URL
+            else if (line.rfind("commercial_url", 0) == 0) {
+                commercial_contact_url = line.substr(14);
+            }
+            // PSD Type 6: Commercial (COMR) - Received as
+            else if (line.rfind("commercial_received", 0) == 0) {
+                commercial_received_as = line.substr(19);
+            }
+            // PSD Type 6: Commercial (COMR) - Seller
+            else if (line.rfind("commercial_seller", 0) == 0) {
+                commercial_seller = line.substr(17);
+            }
+            // PSD Type 6: Commercial (COMR) - Description
+            else if (line.rfind("commercial_desc", 0) == 0) {
+                commercial_description = line.substr(15);
+            }
+            // PSD Type 7: Reference Identifier (UFID) - Owner
+            else if (line.rfind("ufid_owner", 0) == 0) {
+                ufid_owner = line.substr(10);
+            }
+            // PSD Type 7: Reference Identifier (UFID) - Identifier
+            else if (line.rfind("ufid_id", 0) == 0) {
+                ufid_identifier = line.substr(7);
+            }
+            // Album art LOT
+            else if (line.rfind("lot", 0) == 0) {
                 try {
-                    lot = std::stoi(line.substr(3, msg_len - 3));
+                    lot = std::stoi(line.substr(3));
                 } catch (std::invalid_argument& err) {
                     // ignore
                 }
diff --git a/lib/psd_encoder_impl.h b/lib/psd_encoder_impl.h
index eaaf957..e3e12f1 100644
--- a/lib/psd_encoder_impl.h
+++ b/lib/psd_encoder_impl.h
@@ -24,6 +24,19 @@ class psd_encoder_impl : public psd_encoder
     int prog_num;
     std::string title;
     std::string artist;
+    std::string album;
+    std::string genre;
+    std::string comment_language;
+    std::string comment_short_desc;
+    std::string comment_text;
+    std::string commercial_price;
+    std::string commercial_valid_until;
+    std::string commercial_contact_url;
+    std::string commercial_received_as;
+    std::string commercial_seller;
+    std::string commercial_description;
+    std::string ufid_owner;
+    std::string ufid_identifier;
     int lot;
     int bytes_per_frame;
     uint16_t seq_num;
@@ -35,6 +48,9 @@ class psd_encoder_impl : public psd_encoder
     std::string encode_psd_packet(uint8_t dtpf, uint16_t port, uint16_t seq);
     std::string encode_id3();
     std::string encode_text_frame(const std::string& id, const std::string& data);
+    std::string encode_comment_frame(const std::string& language, const std::string& short_desc, const std::string& text);
+    std::string encode_commercial_frame(const std::string& price, const std::string& valid_until, const std::string& contact_url, const std::string& received_as, const std::string& seller, const std::string& description);
+    std::string encode_ufid_frame(const std::string& owner, const std::string& identifier);
     std::string encode_xhdr_frame();
 
     void handle_clock(pmt::pmt_t msg);
@@ -44,6 +60,11 @@ class psd_encoder_impl : public psd_encoder
     psd_encoder_impl(const int prog_num,
                      const std::string& title,
                      const std::string& artist,
+                     const std::string& album,
+                     const std::string& genre,
+                     const std::string& comment_language,
+                     const std::string& comment_short_desc,
+                     const std::string& comment_text,
                      const int bytes_per_frame = 0);
     ~psd_encoder_impl();
 
diff --git a/lib/sis_encoder_impl.cc b/lib/sis_encoder_impl.cc
index 36c907c..79d2183 100644
--- a/lib/sis_encoder_impl.cc
+++ b/lib/sis_encoder_impl.cc
@@ -32,7 +32,15 @@ sis_encoder::sptr sis_encoder::make(const pids_mode mode,
                                     float longitude,
                                     float altitude,
                                     const std::string& country_code,
-                                    const unsigned int fcc_facility_id)
+                                    const unsigned int fcc_facility_id,
+                                    const std::vector<data_channel_config> data_channels,
+                                    const std::string& exciter_manufacturer_id,
+                                    const std::string& importer_manufacturer_id,
+                                    const std::vector<unsigned int> exciter_core_version,
+                                    const std::vector<unsigned int> exciter_mfr_version,
+                                    const std::vector<unsigned int> importer_core_version,
+                                    const std::vector<unsigned int> importer_mfr_version,
+                                    const unsigned int importer_configuration_number)
 {
     return gnuradio::get_initial_sptr(new sis_encoder_impl(mode,
                                                            short_name,
@@ -46,7 +54,15 @@ sis_encoder::sptr sis_encoder::make(const pids_mode mode,
                                                            longitude,
                                                            altitude,
                                                            country_code,
-                                                           fcc_facility_id));
+                                                           fcc_facility_id,
+                                                           data_channels,
+                                                           exciter_manufacturer_id,
+                                                           importer_manufacturer_id,
+                                                           exciter_core_version,
+                                                           exciter_mfr_version,
+                                                           importer_core_version,
+                                                           importer_mfr_version,
+                                                           importer_configuration_number));
 }
 
 
@@ -65,7 +81,15 @@ sis_encoder_impl::sis_encoder_impl(const pids_mode mode,
                                    const float longitude,
                                    const float altitude,
                                    const std::string& country_code,
-                                   const unsigned int fcc_facility_id)
+                                   const unsigned int fcc_facility_id,
+                                   const std::vector<data_channel_config> data_channels,
+                                   const std::string& exciter_manufacturer_id,
+                                   const std::string& importer_manufacturer_id,
+                                   const std::vector<unsigned int> exciter_core_version,
+                                   const std::vector<unsigned int> exciter_mfr_version,
+                                   const std::vector<unsigned int> importer_core_version,
+                                   const std::vector<unsigned int> importer_mfr_version,
+                                   const unsigned int importer_configuration_number)
     : gr::sync_block("sis_encoder",
                      gr::io_signature::make(0, 0, 0),
                      gr::io_signature::make(1, 1, sizeof(unsigned char) * SIS_BITS))
@@ -116,6 +140,7 @@ sis_encoder_impl::sis_encoder_impl(const pids_mode mode,
     this->program_types = program_types;
     this->data_types = data_types;
     this->data_mime_types = data_mime_types;
+    this->data_channels = data_channels;
     this->slogan = slogan;
     this->message = message;
     this->emergency_alert = "";
@@ -130,17 +155,21 @@ sis_encoder_impl::sis_encoder_impl(const pids_mode mode,
     dst_sched = dst_schedule::US_CANADA;
     dst_local = true;
     dst_regional = true;
-    exciter_manufacturer_id = "CS";
-    exciter_core_version = { 1, 0, 0, 0 };
+    this->exciter_manufacturer_id = exciter_manufacturer_id;
+    this->exciter_core_version = exciter_core_version;
+    while (this->exciter_core_version.size() < 4) this->exciter_core_version.push_back(0);
     exciter_core_status = 0;
-    exciter_manufacturer_version = { 1, 0, 0, 0 };
+    this->exciter_manufacturer_version = exciter_mfr_version;
+    while (this->exciter_manufacturer_version.size() < 4) this->exciter_manufacturer_version.push_back(0);
     exciter_manufacturer_status = 0;
-    importer_manufacturer_id = "CS";
-    importer_core_version = { 1, 0, 0, 0 };
+    this->importer_manufacturer_id = importer_manufacturer_id;
+    this->importer_core_version = importer_core_version;
+    while (this->importer_core_version.size() < 4) this->importer_core_version.push_back(0);
     importer_core_status = 0;
-    importer_manufacturer_version = { 1, 0, 0, 0 };
+    this->importer_manufacturer_version = importer_mfr_version;
+    while (this->importer_manufacturer_version.size() < 4) this->importer_manufacturer_version.push_back(0);
     importer_manufacturer_status = 0;
-    importer_configuration_number = 0;
+    this->importer_configuration_number = importer_configuration_number;
 
     long_name_current_frame = 0;
     long_name_seq = 0;
@@ -482,10 +511,13 @@ void sis_encoder_impl::write_station_location()
     write_int(static_cast<int>(msg_id::STATION_LOCATION), 4);
     write_bit(location_high);
     if (location_high) {
-        write_int(std::round(latitude * 8192), 22);
-        write_int(altitude_int >> 4, 4);
+        write_int(static_cast<int>(std::round(latitude * 8192)), 22);
+        // Decoder expects bits to reconstruct altitude << 4
+        // High message gets upper 4 bits of the 8-bit value (bits 7-4)
+        write_int((altitude_int >> 4) & 0xf, 4);
     } else {
-        write_int(std::round(longitude * 8192), 22);
+        write_int(static_cast<int>(std::round(longitude * 8192)), 22);
+        // Low message gets lower 4 bits of the 8-bit value (bits 3-0)
         write_int(altitude_int & 0xf, 4);
     }
 
@@ -538,14 +570,18 @@ void sis_encoder_impl::write_service_information_message()
 {
     write_int(static_cast<int>(msg_id::SERVICE_INFORMATION_MESSAGE), 4);
 
+    unsigned int total_services = program_types.size() + data_types.size() + data_channels.size();
+
     if (current_service < program_types.size()) {
+        // Audio service descriptor
         write_int(static_cast<int>(service_category::AUDIO), 2);
         write_bit(static_cast<int>(access::PUBLIC));
         write_int(current_service, 6);
         write_int(static_cast<int>(program_types[current_service]), 8);
         write_int(0, 5); // reserved
         write_int(static_cast<int>(sound_experience::NONE), 5);
-    } else {
+    } else if (current_service < program_types.size() + data_types.size()) {
+        // Legacy data service descriptor (e.g. emergency alerts)
         unsigned int data_index = current_service - program_types.size();
 
         write_int(static_cast<int>(service_category::DATA), 2);
@@ -553,9 +589,19 @@ void sis_encoder_impl::write_service_information_message()
         write_int(static_cast<int>(data_types[data_index]), 9);
         write_int(0, 3); // reserved
         write_int(data_mime_types[data_index], 12);
+    } else {
+        // Data-only channel service descriptor (from data_channels config)
+        unsigned int dc_index = current_service - program_types.size() - data_types.size();
+        const auto& dc = data_channels[dc_index];
+
+        write_int(static_cast<int>(service_category::DATA), 2);
+        write_bit(static_cast<int>(access::PUBLIC));
+        write_int(dc.sdt, 9);
+        write_int(0, 3); // reserved
+        write_int(dc.mime & 0xFFF, 12); // 12 LSBs of MIME hash
     }
 
-    current_service = (current_service + 1) % (program_types.size() + data_types.size());
+    current_service = (current_service + 1) % total_services;
 }
 
 void sis_encoder_impl::write_sis_parameter_message()
@@ -735,9 +781,9 @@ void sis_encoder_impl::write_emergency_alert()
 std::string sis_encoder_impl::generate_sig()
 {
     std::stringstream out;
-    unsigned int program_id = 0;
     unsigned int port = 0x1000;
 
+    // Emit AUDIO services for each program (album art + station logo per program)
     for (unsigned int program_id = 0; program_id < program_names.size(); program_id++) {
         unsigned int component_id = 0;
 
@@ -762,6 +808,33 @@ std::string sis_encoder_impl::generate_sig()
                                            0x32 + program_id);
     }
 
+    // Emit DATA services for each configured data-only channel.
+    // Each data channel gets its own DATA service with one LOT data component.
+    // This is the critical piece that tells the decoder to reassemble LOT
+    // objects arriving on these ports.
+    unsigned int data_service_number = program_names.size() + 1;
+    for (unsigned int i = 0; i < data_channels.size(); i++) {
+        const auto& dc = data_channels[i];
+        unsigned int component_id = 0;
+
+        // Use the custom name if provided, otherwise generate a default name
+        std::string svc_name = dc.name.empty() ? ("Data" + std::to_string(i + 1)) : dc.name;
+
+        out << generate_sig_service(
+            sig_service_type::DATA, data_service_number++, svc_name);
+
+        // Determine the MIME hash to use in the SIG component.
+        // If mime is 0, default to TEXT; otherwise use what was configured.
+        mime_hash mh = static_cast<mime_hash>(dc.mime ? dc.mime : static_cast<uint32_t>(mime_hash::TEXT));
+
+        out << generate_sig_data_component(component_id++,
+                                           dc.port,
+                                           static_cast<service_data_type>(dc.sdt),
+                                           data_type::LOT,
+                                           mh,
+                                           dc.lot_id);
+    }
+
     return out.str();
 }
 
@@ -886,7 +959,217 @@ void sis_encoder_impl::handle_command(pmt::pmt_t msg)
 
             auto command = command_line.substr(0, command_line.find('|'));
 
-            if (command == "clear_alert") {
+            if (command == "set_param") {
+                // set_param|<index>|<value>
+                // Sets SIS Parameter Message index directly.
+                // Index 0-12 per Table 4-14 of SY_IDD_1020s.
+                // Value is interpreted per index:
+                //   0: Leap Second Offset -- value = pending<<8|current (hex or dec)
+                //   1: Leap Second ALFN LSB -- value = 16-bit LSB
+                //   2: Leap Second ALFN MSB -- value = 16-bit MSB
+                //   3: Local Time Data -- value = utc_offset (signed minutes from UTC)
+                //   4: Exciter Manufacturer ID -- value = two ISO 8859-1 chars (e.g. "CS")
+                //   5: Exciter Core Version 1.2.3 -- value = "L1.L2.L3"
+                //   6: Exciter Mfr Version 1.2.3 -- value = "L1.L2.L3"
+                //   7: Exciter Version 4 & Status -- value = "core4.mfr4.core_status.mfr_status"
+                //   8: Importer Manufacturer ID -- value = two ISO 8859-1 chars
+                //   9: Importer Core Version 1.2.3 -- value = "L1.L2.L3"
+                //  10: Importer Mfr Version 1.2.3 -- value = "L1.L2.L3"
+                //  11: Importer Version 4 & Status -- value = "core4.mfr4.core_status.mfr_status"
+                //  12: Importer Configuration Number -- value = 0-65535
+                auto rest = command_line.substr(10); // after "set_param|"
+                auto sep1 = rest.find('|');
+                if (sep1 != std::string::npos) {
+                    int idx = std::stoi(rest.substr(0, sep1));
+                    std::string val = rest.substr(sep1 + 1);
+                    // Remove trailing newline if present
+                    if (!val.empty() && val.back() == '\n') val.pop_back();
+
+                    switch (idx) {
+                    case 0: {
+                        // Leap Second Offset: pending|current or single hex value
+                        auto pipe = val.find('|');
+                        if (pipe != std::string::npos) {
+                            pending_leap_second_offset = std::stoi(val.substr(0, pipe));
+                            current_leap_second_offset = std::stoi(val.substr(pipe + 1));
+                        } else {
+                            unsigned int v = std::stoul(val, nullptr, 0);
+                            pending_leap_second_offset = (v >> 8) & 0xFF;
+                            current_leap_second_offset = v & 0xFF;
+                        }
+                        d_logger->info("set leap second offset: pending=" +
+                                      std::to_string(pending_leap_second_offset) +
+                                      " current=" + std::to_string(current_leap_second_offset));
+                        break;
+                    }
+                    case 1: {
+                        // Leap Second ALFN LSB
+                        unsigned int lsb = std::stoul(val, nullptr, 0);
+                        leap_second_alfn = (leap_second_alfn & 0xFFFF0000) | (lsb & 0xFFFF);
+                        d_logger->info("set leap second ALFN LSB: " + std::to_string(lsb));
+                        break;
+                    }
+                    case 2: {
+                        // Leap Second ALFN MSB
+                        unsigned int msb = std::stoul(val, nullptr, 0);
+                        leap_second_alfn = (leap_second_alfn & 0x0000FFFF) | ((msb & 0xFFFF) << 16);
+                        d_logger->info("set leap second ALFN MSB: " + std::to_string(msb));
+                        break;
+                    }
+                    case 3: {
+                        // Local Time Data: utc_offset in minutes (signed)
+                        // Optionally: utc_offset|dst_sched|dst_local|dst_regional
+                        auto parts_str = val;
+                        std::vector<std::string> parts_vec;
+                        size_t pos2 = 0;
+                        while ((pos2 = parts_str.find('|')) != std::string::npos) {
+                            parts_vec.push_back(parts_str.substr(0, pos2));
+                            parts_str.erase(0, pos2 + 1);
+                        }
+                        parts_vec.push_back(parts_str);
+
+                        utc_offset = std::stoi(parts_vec[0]);
+                        if (parts_vec.size() > 1) {
+                            int ds = std::stoi(parts_vec[1]);
+                            dst_sched = static_cast<dst_schedule>(ds);
+                        }
+                        if (parts_vec.size() > 2) dst_local = (parts_vec[2] == "1");
+                        if (parts_vec.size() > 3) dst_regional = (parts_vec[3] == "1");
+                        d_logger->info("set local time: utc_offset=" + std::to_string(utc_offset));
+                        break;
+                    }
+                    case 4: {
+                        // Exciter Manufacturer ID (2 chars)
+                        if (val.length() >= 2) {
+                            exciter_manufacturer_id = val.substr(0, 2);
+                            d_logger->info("set exciter manufacturer ID: " + exciter_manufacturer_id);
+                        } else {
+                            d_logger->error("exciter manufacturer ID must be 2 characters");
+                        }
+                        break;
+                    }
+                    case 5: {
+                        // Exciter Core Version L1.L2.L3
+                        std::vector<std::string> levels;
+                        size_t pos2 = 0;
+                        std::string tmp = val;
+                        while ((pos2 = tmp.find('.')) != std::string::npos) {
+                            levels.push_back(tmp.substr(0, pos2));
+                            tmp.erase(0, pos2 + 1);
+                        }
+                        levels.push_back(tmp);
+                        for (int lv = 0; lv < 3 && lv < (int)levels.size(); lv++) {
+                            exciter_core_version[lv] = std::stoi(levels[lv]);
+                        }
+                        d_logger->info("set exciter core version");
+                        break;
+                    }
+                    case 6: {
+                        // Exciter Mfr Version L1.L2.L3
+                        std::vector<std::string> levels;
+                        size_t pos2 = 0;
+                        std::string tmp = val;
+                        while ((pos2 = tmp.find('.')) != std::string::npos) {
+                            levels.push_back(tmp.substr(0, pos2));
+                            tmp.erase(0, pos2 + 1);
+                        }
+                        levels.push_back(tmp);
+                        for (int lv = 0; lv < 3 && lv < (int)levels.size(); lv++) {
+                            exciter_manufacturer_version[lv] = std::stoi(levels[lv]);
+                        }
+                        d_logger->info("set exciter manufacturer version");
+                        break;
+                    }
+                    case 7: {
+                        // Exciter Version 4 & Status: core4.mfr4.core_status.mfr_status
+                        std::vector<std::string> parts_v;
+                        size_t pos2 = 0;
+                        std::string tmp = val;
+                        while ((pos2 = tmp.find('.')) != std::string::npos) {
+                            parts_v.push_back(tmp.substr(0, pos2));
+                            tmp.erase(0, pos2 + 1);
+                        }
+                        parts_v.push_back(tmp);
+                        if (parts_v.size() > 0) exciter_core_version[3] = std::stoi(parts_v[0]);
+                        if (parts_v.size() > 1) exciter_manufacturer_version[3] = std::stoi(parts_v[1]);
+                        if (parts_v.size() > 2) exciter_core_status = std::stoi(parts_v[2]);
+                        if (parts_v.size() > 3) exciter_manufacturer_status = std::stoi(parts_v[3]);
+                        d_logger->info("set exciter version 4 and status");
+                        break;
+                    }
+                    case 8: {
+                        // Importer Manufacturer ID (2 chars)
+                        if (val.length() >= 2) {
+                            importer_manufacturer_id = val.substr(0, 2);
+                            d_logger->info("set importer manufacturer ID: " + importer_manufacturer_id);
+                        } else {
+                            d_logger->error("importer manufacturer ID must be 2 characters");
+                        }
+                        break;
+                    }
+                    case 9: {
+                        // Importer Core Version L1.L2.L3
+                        std::vector<std::string> levels;
+                        size_t pos2 = 0;
+                        std::string tmp = val;
+                        while ((pos2 = tmp.find('.')) != std::string::npos) {
+                            levels.push_back(tmp.substr(0, pos2));
+                            tmp.erase(0, pos2 + 1);
+                        }
+                        levels.push_back(tmp);
+                        for (int lv = 0; lv < 3 && lv < (int)levels.size(); lv++) {
+                            importer_core_version[lv] = std::stoi(levels[lv]);
+                        }
+                        d_logger->info("set importer core version");
+                        break;
+                    }
+                    case 10: {
+                        // Importer Mfr Version L1.L2.L3
+                        std::vector<std::string> levels;
+                        size_t pos2 = 0;
+                        std::string tmp = val;
+                        while ((pos2 = tmp.find('.')) != std::string::npos) {
+                            levels.push_back(tmp.substr(0, pos2));
+                            tmp.erase(0, pos2 + 1);
+                        }
+                        levels.push_back(tmp);
+                        for (int lv = 0; lv < 3 && lv < (int)levels.size(); lv++) {
+                            importer_manufacturer_version[lv] = std::stoi(levels[lv]);
+                        }
+                        d_logger->info("set importer manufacturer version");
+                        break;
+                    }
+                    case 11: {
+                        // Importer Version 4 & Status: core4.mfr4.core_status.mfr_status
+                        std::vector<std::string> parts_v;
+                        size_t pos2 = 0;
+                        std::string tmp = val;
+                        while ((pos2 = tmp.find('.')) != std::string::npos) {
+                            parts_v.push_back(tmp.substr(0, pos2));
+                            tmp.erase(0, pos2 + 1);
+                        }
+                        parts_v.push_back(tmp);
+                        if (parts_v.size() > 0) importer_core_version[3] = std::stoi(parts_v[0]);
+                        if (parts_v.size() > 1) importer_manufacturer_version[3] = std::stoi(parts_v[1]);
+                        if (parts_v.size() > 2) importer_core_status = std::stoi(parts_v[2]);
+                        if (parts_v.size() > 3) importer_manufacturer_status = std::stoi(parts_v[3]);
+                        d_logger->info("set importer version 4 and status");
+                        break;
+                    }
+                    case 12: {
+                        // Importer Configuration Number
+                        importer_configuration_number = std::stoul(val, nullptr, 0);
+                        d_logger->info("set importer config number: " + std::to_string(importer_configuration_number));
+                        break;
+                    }
+                    default:
+                        d_logger->error("set_param: invalid index " + std::to_string(idx) + " (valid: 0-12)");
+                        break;
+                    }
+                } else {
+                    d_logger->error("set_param: missing index or value");
+                }
+            } else if (command == "clear_alert") {
                 this->emergency_alert = "";
                 this->emergency_alert_cnt_len = 0;
                 d_logger->info("clearing emergency alert");
diff --git a/lib/sis_encoder_impl.h b/lib/sis_encoder_impl.h
index c96c292..80bc7e8 100644
--- a/lib/sis_encoder_impl.h
+++ b/lib/sis_encoder_impl.h
@@ -287,6 +287,7 @@ class sis_encoder_impl : public sis_encoder
     std::vector<program_type> program_types;
     std::vector<service_data_type> data_types;
     std::vector<unsigned int> data_mime_types;
+    std::vector<data_channel_config> data_channels;
     unsigned int current_service;
 
     unsigned int current_parameter;
@@ -346,7 +347,15 @@ class sis_encoder_impl : public sis_encoder
         const float longitude = -74.0445,
         const float altitude = 93.0,
         const std::string& country_code = "US",
-        const unsigned int fcc_facility_id = 0);
+        const unsigned int fcc_facility_id = 0,
+        const std::vector<data_channel_config> data_channels = {},
+        const std::string& exciter_manufacturer_id = "CS",
+        const std::string& importer_manufacturer_id = "CS",
+        const std::vector<unsigned int> exciter_core_version = { 1, 0, 0, 0 },
+        const std::vector<unsigned int> exciter_mfr_version = { 1, 0, 0, 0 },
+        const std::vector<unsigned int> importer_core_version = { 1, 0, 0, 0 },
+        const std::vector<unsigned int> importer_mfr_version = { 1, 0, 0, 0 },
+        const unsigned int importer_configuration_number = 0);
     ~sis_encoder_impl();
 
     // Where all the action really happens
diff --git a/python/bindings/am_pulse_shaper_python.cc b/python/bindings/am_pulse_shaper_python.cc
index 855faee..c914643 100644
--- a/python/bindings/am_pulse_shaper_python.cc
+++ b/python/bindings/am_pulse_shaper_python.cc
@@ -14,7 +14,7 @@
 /* BINDTOOL_GEN_AUTOMATIC(1)                                                       */
 /* BINDTOOL_USE_PYGCCXML(0)                                                        */
 /* BINDTOOL_HEADER_FILE(am_pulse_shaper.h)                                        */
-/* BINDTOOL_HEADER_FILE_HASH(63976a7ef63bf73db3b965a0f491ce28)                     */
+/* BINDTOOL_HEADER_FILE_HASH(0)                     */
 /***********************************************************************************/
 
 #include <pybind11/complex.h>
diff --git a/python/bindings/hdc_encoder_python.cc b/python/bindings/hdc_encoder_python.cc
index 9a3625a..8bcd1b4 100644
--- a/python/bindings/hdc_encoder_python.cc
+++ b/python/bindings/hdc_encoder_python.cc
@@ -14,7 +14,7 @@
 /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
 /* BINDTOOL_USE_PYGCCXML(0)                                                        */
 /* BINDTOOL_HEADER_FILE(hdc_encoder.h)                                        */
-/* BINDTOOL_HEADER_FILE_HASH(189e984318a00d48a752b2e0010ef257)                     */
+/* BINDTOOL_HEADER_FILE_HASH(0)                                                    */
 /***********************************************************************************/
 
 #include <pybind11/complex.h>
@@ -39,6 +39,8 @@ void bind_hdc_encoder(py::module& m)
         .def(py::init(&hdc_encoder::make),
            py::arg("channels") = 2,
            py::arg("bitrate") = 64000,
+           py::arg("use_parametric_stereo") = false,
+           py::arg("tx_digital_gain") = 0,
            D(hdc_encoder,make)
         )
 
diff --git a/python/bindings/l1_am_encoder_python.cc b/python/bindings/l1_am_encoder_python.cc
index e025af7..519ccc6 100644
--- a/python/bindings/l1_am_encoder_python.cc
+++ b/python/bindings/l1_am_encoder_python.cc
@@ -14,7 +14,7 @@
 /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
 /* BINDTOOL_USE_PYGCCXML(0)                                                        */
 /* BINDTOOL_HEADER_FILE(l1_am_encoder.h)                                        */
-/* BINDTOOL_HEADER_FILE_HASH(96b80cbeab3f9da9b4a52abeeb3986fb)                     */
+/* BINDTOOL_HEADER_FILE_HASH(0)                     */
 /***********************************************************************************/
 
 #include <pybind11/complex.h>
diff --git a/python/bindings/l1_fm_encoder_python.cc b/python/bindings/l1_fm_encoder_python.cc
index e436299..8975f7e 100644
--- a/python/bindings/l1_fm_encoder_python.cc
+++ b/python/bindings/l1_fm_encoder_python.cc
@@ -14,7 +14,7 @@
 /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
 /* BINDTOOL_USE_PYGCCXML(0)                                                        */
 /* BINDTOOL_HEADER_FILE(l1_fm_encoder.h)                                        */
-/* BINDTOOL_HEADER_FILE_HASH(28b4c2c78049aedef3c35cd91abd7142)                     */
+/* BINDTOOL_HEADER_FILE_HASH(0)                     */
 /***********************************************************************************/
 
 #include <pybind11/complex.h>
diff --git a/python/bindings/l2_encoder_python.cc b/python/bindings/l2_encoder_python.cc
index 29c978e..76a5d80 100644
--- a/python/bindings/l2_encoder_python.cc
+++ b/python/bindings/l2_encoder_python.cc
@@ -14,7 +14,7 @@
 /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
 /* BINDTOOL_USE_PYGCCXML(0)                                                        */
 /* BINDTOOL_HEADER_FILE(l2_encoder.h)                                        */
-/* BINDTOOL_HEADER_FILE_HASH(e09b3f444566cbfeb2a2798367382fa7)                     */
+/* BINDTOOL_HEADER_FILE_HASH(0)                                                    */
 /***********************************************************************************/
 
 #include <pybind11/complex.h>
@@ -47,6 +47,8 @@ void bind_l2_encoder(py::module& m)
            py::arg("size"),
            py::arg("data_bytes") = 0,
            py::arg("blend_control") = ::gr::nrsc5::blend::ENABLE,
+           py::arg("tx_digital_gain") = 0,
+           py::arg("debug_logs") = false,
            py::arg("ccc_width") = 24,
            D(l2_encoder,make)
         )
diff --git a/python/bindings/psd_encoder_python.cc b/python/bindings/psd_encoder_python.cc
index bef2b96..f7bf08d 100644
--- a/python/bindings/psd_encoder_python.cc
+++ b/python/bindings/psd_encoder_python.cc
@@ -14,7 +14,7 @@
 /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
 /* BINDTOOL_USE_PYGCCXML(0)                                                        */
 /* BINDTOOL_HEADER_FILE(psd_encoder.h)                                        */
-/* BINDTOOL_HEADER_FILE_HASH(aa3c914cdda9eeb1f25aa5201cb775bd)                     */
+/* BINDTOOL_HEADER_FILE_HASH(0)                                                    */
 /***********************************************************************************/
 
 #include <pybind11/complex.h>
@@ -38,8 +38,13 @@ void bind_psd_encoder(py::module& m)
 
         .def(py::init(&psd_encoder::make),
            py::arg("prog_num"),
-           py::arg("title"),
-           py::arg("artist"),
+           py::arg("title") = "",
+           py::arg("artist") = "",
+           py::arg("album") = "",
+           py::arg("genre") = "",
+           py::arg("comment_language") = "",
+           py::arg("comment_short_desc") = "",
+           py::arg("comment_text") = "",
            py::arg("bytes_per_frame") = 0,
            D(psd_encoder,make)
         )
diff --git a/python/bindings/sis_encoder_python.cc b/python/bindings/sis_encoder_python.cc
index a1cb91a..3522f09 100644
--- a/python/bindings/sis_encoder_python.cc
+++ b/python/bindings/sis_encoder_python.cc
@@ -7,15 +7,15 @@
  *
  */
 
-/***********************************************************************************/
+/***/
 /* This file is automatically generated using bindtool and can be manually edited  */
 /* The following lines can be configured to regenerate this file during cmake      */
 /* If manual edits are made, the following tags should be modified accordingly.    */
 /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
 /* BINDTOOL_USE_PYGCCXML(0)                                                        */
 /* BINDTOOL_HEADER_FILE(sis_encoder.h)                                        */
-/* BINDTOOL_HEADER_FILE_HASH(38686eef3cff9a3dab3147ef3ec3001d)                     */
-/***********************************************************************************/
+/* BINDTOOL_HEADER_FILE_HASH(0)                     */
+/***/
 
 #include <pybind11/complex.h>
 #include <pybind11/pybind11.h>
@@ -93,6 +93,26 @@ void bind_sis_encoder(py::module& m)
         .value("AUDIO_RELATED_DATA", ::gr::nrsc5::service_data_type::AUDIO_RELATED_DATA)
         .export_values();
 
+    py::enum_<::gr::nrsc5::mime_hash>(m, "mime_hash")
+        .value("PRIMARY_IMAGE", ::gr::nrsc5::mime_hash::PRIMARY_IMAGE)
+        .value("STATION_LOGO", ::gr::nrsc5::mime_hash::STATION_LOGO)
+        .value("HDC", ::gr::nrsc5::mime_hash::HDC)
+        .value("TEXT", ::gr::nrsc5::mime_hash::TEXT)
+        .value("JPEG", ::gr::nrsc5::mime_hash::JPEG)
+        .value("PNG", ::gr::nrsc5::mime_hash::PNG)
+        .value("GIF", ::gr::nrsc5::mime_hash::GIF)
+        .export_values();
+
+    py::class_<::gr::nrsc5::data_channel_config>(m, "data_channel_config")
+        .def(py::init<>())
+        .def(py::init<uint16_t, uint16_t, unsigned int, uint32_t, const std::string&>(),
+             py::arg("port"), py::arg("lot_id"), py::arg("sdt"), py::arg("mime"), py::arg("name") = "")
+        .def_readwrite("port", &::gr::nrsc5::data_channel_config::port)
+        .def_readwrite("lot_id", &::gr::nrsc5::data_channel_config::lot_id)
+        .def_readwrite("sdt", &::gr::nrsc5::data_channel_config::sdt)
+        .def_readwrite("mime", &::gr::nrsc5::data_channel_config::mime)
+        .def_readwrite("name", &::gr::nrsc5::data_channel_config::name);
+
     py::class_<sis_encoder, gr::sync_block, gr::block, gr::basic_block,
         std::shared_ptr<sis_encoder>>(m, "sis_encoder", D(sis_encoder))
 
@@ -110,9 +130,17 @@ void bind_sis_encoder(py::module& m)
            py::arg("altitude") = 93.0,
            py::arg("country_code") = "US",
            py::arg("fcc_facility_id") = 0,
+           py::arg("data_channels") = std::vector<::gr::nrsc5::data_channel_config>({}),
+           py::arg("exciter_manufacturer_id") = "CS",
+           py::arg("importer_manufacturer_id") = "CS",
+           py::arg("exciter_core_version") = std::vector<unsigned int>({ 1, 0, 0, 0 }),
+           py::arg("exciter_mfr_version") = std::vector<unsigned int>({ 1, 0, 0, 0 }),
+           py::arg("importer_core_version") = std::vector<unsigned int>({ 1, 0, 0, 0 }),
+           py::arg("importer_mfr_version") = std::vector<unsigned int>({ 1, 0, 0, 0 }),
+           py::arg("importer_configuration_number") = 0,
            D(sis_encoder,make)
         )
-        
+
 
 
 
@@ -126,7 +154,3 @@ void bind_sis_encoder(py::module& m)
 
 
 
-
-
-
-
diff --git a/python/lot_encoder.py b/python/lot_encoder.py
index dd05f82..c01d3ad 100644
--- a/python/lot_encoder.py
+++ b/python/lot_encoder.py
@@ -9,6 +9,7 @@
 import os
 import pmt
 import struct
+import re
 from datetime import datetime, timedelta, timezone
 from gnuradio import gr
 
@@ -18,12 +19,15 @@ class lot_encoder(gr.basic_block):
     PNG_START = bytes.fromhex("89504E470D0A1A0A")
     JPEG_START = bytes.fromhex("FFD8")
     JPEG_END = bytes.fromhex("FFD9")
+    GIF87A_START = bytes.fromhex("474946383761")  # "GIF87a"
+    GIF89A_START = bytes.fromhex("474946383961")  # "GIF89a"
 
     MIMEHASH_PNG = 0x4F328CA0
     MIMEHASH_JPEG = 0x1E653E9C
     MIMEHASH_TEXT = 0xBB492AAC
+    MIMEHASH_GIF = 0x87A4FD95
 
-    def __init__(self, filename="", lot_id=0, port=0x1001):
+    def __init__(self, filename="", lot_id=0, port=0x1001, expiry="45 minutes"):
         gr.sync_block.__init__(
             self,
             name='LOT encoder',
@@ -39,13 +43,93 @@ def __init__(self, filename="", lot_id=0, port=0x1001):
         self.set_msg_handler(pmt.intern("ready"), self.handle_notify)
 
         self.port = port
-        with open(filename, "rb") as f:
-            self.prepare_file(os.path.basename(filename), f.read(), lot_id)
-
+        self.default_expiry = expiry
+        self.current_part_index = 0
         self.command_buffer = bytes()
 
+        # Initialize logger first before using it
         self.my_log = gr.logger(self.alias())
 
+        # Now prepare the file (which may use the logger)
+        with open(filename, "rb") as f:
+            self.prepare_file(os.path.basename(filename), f.read(), lot_id, expiry)
+
+    def parse_relative_time(self, time_str):
+        """
+        Parse relative time strings like '15 minutes', '2 weeks', '1 year', etc.
+        Returns a timedelta object.
+        """
+        time_str = time_str.strip().lower()
+
+        # Pattern: number + optional space + unit
+        pattern = r'^(\d+(?:\.\d+)?)\s*(ms|mil|milliseconds?|s|sec|seconds?|m|min|minutes?|h|hr|hours?|d|days?|w|wk|weeks?|mn|month|months?|y|yr|year|years?)$'
+        match = re.match(pattern, time_str)
+
+        if not match:
+            raise ValueError(f"Invalid relative time format: {time_str}")
+
+        value = float(match.group(1))
+        unit = match.group(2)
+
+        # Convert to timedelta
+        if unit in ('ms', 'mil', 'millisecond', 'milliseconds'):
+            return timedelta(milliseconds=value)
+        elif unit in ('s', 'sec', 'second', 'seconds'):
+            return timedelta(seconds=value)
+        elif unit in ('m', 'min', 'minute', 'minutes'):
+            return timedelta(minutes=value)
+        elif unit in ('h', 'hr', 'hour', 'hours'):
+            return timedelta(hours=value)
+        elif unit in ('d', 'day', 'days'):
+            return timedelta(days=value)
+        elif unit in ('w', 'wk', 'week', 'weeks'):
+            return timedelta(weeks=value)
+        elif unit in ('mn', 'month', 'months'):
+            return timedelta(days=value * 30.44)  # Average month length
+        elif unit in ('y', 'yr', 'year', 'years'):
+            return timedelta(days=value * 365.25)  # Account for leap years
+        else:
+            raise ValueError(f"Unknown time unit: {unit}")
+
+    def parse_expiry(self, expiry_str):
+        """
+        Parse expiry date/time. Supports:
+        - TZ format: ISO 8601 datetime with timezone (e.g., '2026-12-31T23:59:59+00:00')
+        - Relative time: '15 minutes', '2 weeks', '1 year', etc.
+        Returns a datetime object in UTC.
+        """
+        if not expiry_str or expiry_str.strip() == "":
+            # Default to 45 minutes
+            return datetime.now(timezone.utc) + timedelta(minutes=45)
+
+        expiry_str = expiry_str.strip()
+
+        # Try parsing as ISO 8601 / TZ format first
+        try:
+            # Try various ISO 8601 formats
+            for fmt in ['%Y-%m-%dT%H:%M:%S%z', '%Y-%m-%dT%H:%M:%S.%f%z',
+                       '%Y-%m-%d %H:%M:%S%z', '%Y-%m-%dT%H:%M:%SZ']:
+                try:
+                    if fmt.endswith('Z'):
+                        # Handle 'Z' suffix for UTC
+                        dt = datetime.strptime(expiry_str, fmt).replace(tzinfo=timezone.utc)
+                    else:
+                        dt = datetime.strptime(expiry_str, fmt)
+                    return dt.astimezone(timezone.utc)
+                except ValueError:
+                    continue
+        except Exception:
+            pass
+
+        # Try parsing as relative time
+        try:
+            delta = self.parse_relative_time(expiry_str)
+            return datetime.now(timezone.utc) + delta
+        except ValueError as e:
+            self.my_log.error(f"Failed to parse expiry time '{expiry_str}': {e}")
+            # Default to 45 minutes
+            return datetime.now(timezone.utc) + timedelta(minutes=45)
+
     def handle_new_file(self, msg):
         data = bytes(pmt.to_python(msg)[1])
         self.command_buffer += data
@@ -55,19 +139,21 @@ def handle_new_file(self, msg):
             command = self.command_buffer[:command_end]
             parts = command.split(b"|")
 
-            if (parts[0] == b"streamfile") and (len(parts) == 4):
+            if (parts[0] == b"streamfile") and (len(parts) >= 4):
                 lot_id = int(parts[1])
                 size = int(parts[2])
                 filename = parts[3]
+                expiry = parts[4].decode('utf-8') if len(parts) >= 5 else self.default_expiry
                 if len(self.command_buffer) >= command_end + 1 + size:
                     filedata = self.command_buffer[command_end + 1:command_end + 1 + size]
-                    self.prepare_file(filename, filedata, lot_id)
+                    self.prepare_file(filename, filedata, lot_id, expiry)
                     self.command_buffer = self.command_buffer[command_end + 1 + size:]
-            elif (parts[0] == b"file") and (len(parts) == 3):
+            elif (parts[0] == b"file") and (len(parts) >= 3):
                 lot_id = int(parts[1])
                 filename = parts[2]
+                expiry = parts[3].decode('utf-8') if len(parts) >= 4 else self.default_expiry
                 with open(filename, "rb") as f:
-                    self.prepare_file(os.path.basename(filename), f.read(), lot_id)
+                    self.prepare_file(os.path.basename(filename), f.read(), lot_id, expiry)
                 self.command_buffer = self.command_buffer[command_end + 1:]
             else:
                 self.my_log.warn(f"Invalid command: {command}")
@@ -78,10 +164,23 @@ def handle_notify(self, msg):
         if port == self.port:
             self.send()
 
-    def prepare_file(self, filename, data, lot_id):
+    def prepare_file(self, filename, data, lot_id, expiry_str=None):
         if isinstance(filename, str):
             filename = filename.encode()
 
+        # Parse expiry time
+        if expiry_str is None:
+            expiry_str = self.default_expiry
+
+        dt = self.parse_expiry(expiry_str)
+
+        # Encode expiry in HD Radio format: YYYYMMMMDDDDDHHHHHHMMMMMM (26 bits)
+        # Year: 12 bits (0-4095), Month: 4 bits (1-12), Day: 5 bits (1-31),
+        # Hour: 5 bits (0-23), Minute: 6 bits (0-59), Second: not included
+        expiry_encoded = (dt.year << 20) | (dt.month << 16) | (dt.day << 11) | (dt.hour << 6) | dt.minute
+
+        self.my_log.info(f"LOT {lot_id}: Expiry set to {dt.isoformat()} (encoded: 0x{expiry_encoded:08x})")
+
         parts = []
 
         for offset in range(0, len(data), 256):
@@ -99,40 +198,58 @@ def prepare_file(self, filename, data, lot_id):
             if seq == 0:
                 version = 1
 
-                dt = datetime.now(timezone.utc) + timedelta(days=365)
-                expiry = (dt.year << 20) | (dt.month << 16) | (dt.day << 11) | (dt.hour << 6) | dt.minute
-
                 size = len(data)
 
                 if data.startswith(self.PNG_START):
                     mime = self.MIMEHASH_PNG
                 elif data.startswith(self.JPEG_START) and data.endswith(self.JPEG_END):
                     mime = self.MIMEHASH_JPEG
+                elif data.startswith(self.GIF87A_START) or data.startswith(self.GIF89A_START):
+                    mime = self.MIMEHASH_GIF
                 elif filename.lower().endswith(b".png"):
                     mime = self.MIMEHASH_PNG
                 elif filename.lower().endswith(b".jpg") or filename.lower().endswith(b".jpeg"):
                     mime = self.MIMEHASH_JPEG
+                elif filename.lower().endswith(b".gif"):
+                    mime = self.MIMEHASH_GIF
                 elif filename.lower().endswith(b".txt"):
                     mime = self.MIMEHASH_TEXT
                 else:
-                    raise ValueError("Unsupported file type. Supported types: PNG, JPG, TXT.")
+                    raise ValueError("Unsupported file type. Supported types: PNG, JPG, GIF, TXT.")
 
-                header += struct.pack("<IIII", version, expiry, size, mime) + filename
+                header += struct.pack("<IIII", version, expiry_encoded, size, mime) + filename
 
             parts.append(header + chunk)
 
         self.filename = filename
         self.lot_id = lot_id
         self.parts = parts
+        self.current_part_index = 0
 
     def start(self):
         self.aas_seq = 0
         self.send()
 
     def send(self):
-        self.my_log.info(f"Sending LOT file {self.lot_id}: {self.filename}")
-        for part in self.parts:
+        # Send the entire file to the queue immediately
+        # The L2 encoder will manage the transmission rate
+        # This eliminates the terrible round-trip delay bottleneck
+
+        packets_sent = 0
+        if self.current_part_index == 0:
+            self.my_log.info(f"Sending LOT file {self.lot_id}: {self.filename} ({len(self.parts)} packets)")
+
+        # Send all remaining packets
+        while self.current_part_index < len(self.parts):
+            part = self.parts[self.current_part_index]
             aas_pdu = struct.pack("<BHH", 0x21, self.port, self.aas_seq) + part
             msg = pmt.cons(pmt.make_dict(), pmt.init_u8vector(len(aas_pdu), list(aas_pdu)))
             self.message_port_pub(pmt.intern("aas"), msg)
             self.aas_seq = (self.aas_seq + 1) & 0xffff
+            self.current_part_index += 1
+            packets_sent += 1
+
+        # When we finish the file, loop back to the beginning for continuous transmission
+        if self.current_part_index >= len(self.parts):
+            self.my_log.info(f"Completed sending LOT {self.lot_id}: sent {packets_sent} packets in this burst")
+            self.current_part_index = 0