Proskan mode
Proskan J120
Proskan J120 is a 120 s, 320 x 240 RGB row from the Proskan family.
Reference onlyMode 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 reference-only mode because no matching transmitter entry exists in the app code.
Mode spec
| Short name | J120 |
|---|---|
| Support status | Reference only |
| Spec status | Reference timing row from the OK2MNM SSTV mode-list PDF. |
| Duration | 120 s |
| Frame | 320 x 240 |
| Data lines | 240 |
| Public VIS | VIS 100 |
| Standard VIS code | 0x64 (100) |
| Extended/N-VIS | No |
| Color model | RGB |
| Component sequence | R-G-B |
| Line rate | 128.046 lpm |
| Public timing profile | Mode-list row gives 120 s total duration, 240 scan lines, 320 columns, and 128.046 lpm; line-level porch timing is not part of this catalog row. |
Strengths
- J120 has a concrete catalogue row: 120 s, 320 x 240, RGB, VIS 100.
- J120's R-G-B component order and 128.046 lpm line rate make it useful for comparing airtime, raster, and colour structure against related modes.
Tradeoffs
- J120 is not app-supported yet, so the 120 s / 320 x 240 row should be treated as reference data rather than a verified transmit preset.
- J120 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 SSTV Handbook chapter 5 lists J120 as RGB, VIS 100, 120 s, 240 lines, 320 columns, 128.046 lpm. Proskan J120 analog SSTV reference mode.
- 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.