AVT mode
Amiga Video Transceiver AVT188
AVT188 is a reference-only analog SSTV row with 196 s duration, 320 x 400 raster, RGB color model, and VIS 76, 77, 78, 79.
Needs verificationMode sample
BBC-style colour test card and app-generated audio
The image is generated locally for this mode's raster. For supported modes, the audio sample is encoded from that image with the SSTV Signal Desk transmitter code, then published as lossless FLAC for static playback.
No app-generated audio sample is published for this needs-verification mode because no matching transmitter entry exists in the app code.
Mode spec
| Short name | AVT188 |
|---|---|
| Support status | Needs verification |
| Spec status | OK2MNM table row with a published VIS collision note. |
| Duration | 196 s listed for AVT188 |
| Frame | 320 x 400 |
| Data lines | 400 |
| Public VIS | VIS 76, 77, 78, 79 |
| Standard VIS code | 0x4C, 0x4D, 0x4E, 0x4F (76, 77, 78, 79) |
| Extended/N-VIS | No |
| Color model | RGB |
| Component sequence | R-G-B |
| Line rate | 384 lpm |
| Public timing profile | Mode-list row gives 196 s total duration, 400 scan lines, 320 columns, and 384 lpm; line-level porch timing is not part of this catalog row. |
Strengths
- AVT188 has a concrete catalogue row: 196 s listed for AVT188, 320 x 400, RGB, VIS 76, 77, 78, 79.
- AVT188's R-G-B component order and 384 lpm line rate make it useful for comparing airtime, raster, and colour structure against related modes.
Tradeoffs
- AVT188 is not app-supported yet, so the 196 s listed for AVT188 / 320 x 400 row should be treated as reference data rather than a verified transmit preset.
- AVT188 still needs implementation-grade porch, sync, and pixel timing before an app-generated WAV/FLAC sample can be published with the same confidence as supported modes.
Source notes
OK2MNM lists AVT188 as RGB, VIS 76/77/78/79, 196 s, 400 lines, 320 columns, 384.000 lpm, and notes that AVT188 and Scottie DX accidentally share VIS 76. Known reference-table caveat: AVT188 and Scottie DX can collide in VIS listings.
- SSTV Handbook Chapter 5: List of SSTV modesSSTV Handbook - accessed 2026-08-24Reference for analog SSTV mode names, VIS codes, durations, line counts, column counts, and line rates.
- A Technical Description of SSTV ModesN7CXI Dayton paper - accessed 2026-08-24Classic technical timing reference for Robot, Martin, Scottie, Wraase, Pasokon, PD, and FAX480 families.