in an era where cubesats had about a 50% failure rate.
Phil Karn KA9Q felt that this was mostly because of a poor choice of data link. I think a lot of folks were using AX-25 packet radio, which wasn't intended for satellites. He wrote a modem called BPSK1000 which can tolerate 1-minute fades as a satellite tumbles and the antenna points away from Earth.
Thanks
Bruce
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