AO-51 Mode-S

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I hooked up my Mode-S down converter and quad patch antenna as I saw that AO-51 was running in Mode-S for the next few days.

Here you can see the Doppler shift as AO-51 approaches my QTH. Running at 4 frames per second for the display update so the waterfall represents 50 seconds. I need to add an interface (CAT?) to allow another program to control the frequency. On a subsequent pass I used the sub-rx to track the doppler manually, leaving the main rx on centre frequency of 2401.200.

The antenna was simply sitting on the window ledge of the shack close to a wireless router, hence the strong qrm.