AVT mode
Amiga Video Transceiver AVT48 High
AVT48h is a reference-only analog SSTV row with 48 s duration, 128 x 256 raster, RGB color model, and VIS not confirmed in checked sources.
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 | AVT48h |
|---|---|
| Support status | Needs verification |
| Spec status | Secondary AVT table row. Dayton N7CXI excludes AVT timing tables because it did not have solid author data. |
| Duration | 48 s |
| Frame | 128 x 256 |
| Data lines | 256 |
| Public VIS | VIS not confirmed in checked sources |
| Standard VIS code | Not applicable or not published in checked sources |
| Extended/N-VIS | No |
| Color model | RGB |
| Component sequence | R-G-B |
| Line rate | 320 lpm |
| Public timing profile | Secondary AVT table gives 48 s and 128 x 256. The checked Dayton timing paper explicitly excludes AVT modes, so line-level AVT synchronization is not asserted here. |
Strengths
- AVT48h documents a legacy AVT row with 48 s duration and 128 x 256 raster.
- AVT48h's R-G-B / RGB listing helps separate the AVT family variants before implementation-level timing is available.
Tradeoffs
- AVT48h has no confirmed VIS in the checked sources, so automatic receiver selection cannot be specified from this row alone.
- AVT48h line-level porch timing remains secondary-source context; treat the 48 s entry as historical, not as an app-supported preset.
Source notes
AVT48h is included from a secondary AVT mode table as 48 s and 128 x 256. Dayton N7CXI is cited only for the caveat that AVT timings were excluded from its proposed specifications due lack of solid source data. High AVT 48-second variant; verify exact sync behavior before implementing.
- Slow-scan televisionWikipedia - accessed 2026-08-24Secondary reference used only for legacy AVT 8/16/32/48/104 durations and rasters that are not present in the OK2MNM mode-list PDF.
- 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.