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Page: SW.FBR - Last Modified : Thu, 03 Sep 09

Fleet Broadcast is a 16 channel 75Bd multiplex transmitted from SATCOM satellites on 250.450/550/650 MHz. Modulation is DBPSK 1200Bd, to receive it you need receiver with 2KHz filter and SSB mode. Channel #0 is used for synchronization, other channels are usually filled with pseudo-random crypted data. Sometimes KG84 messages are transmitted. So far no plaintext was ever seen on Fleet Broadcast...

• On top there is status line like [S-r-Ki-i-i--iKii]
  This represents state or detected content of channels as:
  • S = SYNC
  • r = reversals (1010101010 pattern)
  • K = KG84
  • i = idle/constant 1 or 0
  • - = unknown
• Also sync quality (should be 100% all the time with good signal) and increasing frame counter (resets on resync)
• At bottom there is status log with info about KG84 and program status messages
• Hotkeys:
  • Q = exits application
  • S = toggles saving of raw bit stream to files
  • +/- = Tune demodulator frequency, demodulator have AFC and will adjust once tuned -/+100Hz or so

Download: fbr.zip (41kb)