[amsat-bb] Question about PL/CTCSS on uplink

Philip Jenkins n4hf.philip at gmail.com
Sat Feb 3 15:45:15 UTC 2018

I understand why FM satellites need an PL tone on uplink (to keep out
land-mobile services, like taxi-cabs, etc), but why is a PL not required
for the linear sats utilizing the same frequencies? A linear transponder is
certainly capable of receiving/transmitting an FM signal (albeit not
successfully demodulating that signal).

This question came up at a satellite presentation I did, and I had never
thought about it. ( Moreover, will radios even transmit a PL on SSB/CW

Philip N4HF

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