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AO-92 camera mode

Rob Ramsey
 

A little more info please on the camera mode of AO-92 , Is this just a real time transmission as the satellite is overhead or close by? is it stored and sent continuously for a predetermined time? I had my station on remote all day got nothing here in New Zealand ZL3TCM

Clint Bradford
 

It is “near live” - and you’ll probably just receive portions of a photo ...

 

The data is sent as a series of packets using FSK modulation over the FM downlink. There is normally always something being sent as long as the repeater is being kept active, but it is usually sent as slow-speed 200 bps Data-Under-Voice (DUV) in the sub-200 Hz audio range and will be filtered out by most FM receivers as it is in the same range as PL tones. You generally won't hear it in this case. The recent camera experiment is using the High-Speed mode sending at 9600 bps and can clearly be heard over the voice channel even with a regular FM receiver (though some of the important content may still be filtered out). If you are using an SDR receiver to capture the signal, make sure any audio filtering and squelch is turned off during the pass. The audio from either mode can be fed into Foxtelem to decode the satellite telemetry and, if you enable it, can be uploaded to AMSAT servers and attributed to your callsign as helping the greater good.

- Loren
K7IW


On Tue, Apr 28, 2020 at 10:04 PM Rob Ramsey <ramsey4@...> wrote:

A little more info please on the camera mode of AO-92 , Is this just a real time transmission as the satellite is overhead or close by? is it stored and sent continuously for a predetermined time? I had my station on remote all day got nothing here in New Zealand ZL3TCM