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Pasokon mode

Pasokon P3

Pasokon family analog SSTV operation and compatibility reference.

Supported in app

Mode 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.

FLAC, 48 kHz, 16-bit mono, 205.375 s.

P3 SSTV BBC-style colour test card
P3 test card, 640 x 496

Mode spec

Short nameP3
Support statusSupported in app
Spec statusSupported in app; public VIS and timing summary are separated from the app raw timing fields.
Duration203.064 s
Frame640 x 496
Data lines496
Public VISVIS 113 (0x71)
Standard VIS code0x71 (113)
Extended/N-VISNo
Color modelRGB
Component sequenceR-G-B
Line rate146.555 lpm
Public timing profilePublic Pasokon P3 timing: VIS 113; 496 lines; 5.208 ms sync, 1.042 ms porch, then Red, Green, and Blue scans with 133.333 ms color scan time.
App duration203.064 s
App frame640 x 496
App raw VIS0x71 (113)
App timing profileApp RX line fields: sync 5.2 ms; front porch 2.1 ms; back porch 0.8 ms; separator/blank 2.5 ms; video tones 1500-2300 Hz around 1900 Hz.
App RX sync5.2 ms
App RX front porch2.1 ms
App RX back porch0.8 ms
App RX separator/blank2.5 ms
App subcarrier1900 Hz
App deviation400 Hz
App tone range1500-2300 Hz

Strengths

  • P3 is a long-form high-detail Pasokon mode: 203.064 s, 640 x 496, RGB.
  • P3 uses R-G-B RGB component order and VIS 113 (0x71), giving receivers enough mode identity to separate it from neighbouring Pasokon rows.
  • P3 has explicit app timing fields: 5.2 ms sync, 2.1 ms front porch, 0.8 ms back porch, 2.5 ms separator/blank, and 1500-2300 Hz around 1900 Hz video tones.
  • P3 has a checked public timing summary plus app timing fields, so the public spec and implementation timing can be compared line by line.

Tradeoffs

  • P3's 203.064 s transfer can carry more picture detail, but it occupies the channel longer and is less forgiving of fades across the 640 x 496 frame.
  • P3 sends colour sequentially in RGB; sync drift can appear as colour fringing before the whole frame becomes unreadable.

Source notes

Public VIS/timing labels are normalized from checked SSTV references where available. App raw VIS 0x71 and app timing fields are generated from sstv/sstv/sstv/sstvparam.swift during the website build.