[aprssig] Field Day ISS APRS Contacts? Doppler

[Bob Bruninga]

> I have made a few attempts and managed to copy one 
> weak beacon packet. I was at 437.550 +- doppler. 
> It is not easy like the vhf packet was.

And remember TX Doppler is in the opposite direction of RX Doppler.  So you
need 5 memories:

RX 437.560  TX 437.540  Approaching
RX 437.555  TX 437.545
RX 437.550  TX 437.550  Closest point
RX 437.545  TX 437.555
RX 437.540  TX 437.560  Receeding

Bob