17:40 UTC CW, FM
wg9xfc - 1 do
wg9xfc - 1 eo
wg9xfc - 1 a7 - 11
ARDUSAT-1 1 39412U 98067DA 13356.75946265 .00081267 00000-0 11559-2 0 1035 2 39412 051.6508 253.3310 0006443 155.4610 310.8721 15.55634598 5156
What kind of modulation is the signal behind the FM CW signal?
Dear Mike,
My hypothesis for the funny spectrogram for ArduSat FM CW is the following:
These guys are synthesizing the CW audio wave fed to the FM modulator.
The audio wave is sine – DC – sine – DC …
So, whatever phase there is at the end of the CW tone, that will produce a DC value until the next tone carries on.
What I don’t yet understand is why all those DC values are positive (resulting in an FM carrier above Fc). Need to check the software for this last one.
Best regards,
Juan (from Uruguay’s ANTELSAT team)