[amsat-bb] Listening on USB when operating CW

Clayton Coleman kayakfishtx at gmail.com
Fri Feb 7 08:42:36 PST 2014

I assume many home station satellite operators utilize some kind of
full-duplex radio or combination of two radios for CW on the current

Lately, as I have been listening a lot more with my FUNcube Dongle
Pro+, I have observed many CW stations drifting across the satellites'
passband.  I realize this is not a new phenomenon.  I would assume
these drifting stations are NOT using any type of computer Doppler
correction.  If they were using computer control, I would assume their
CW would stay on the same place in the transponder's passband.  It is
visually apparent when the stations manually make larger frequency
movements because of the curve displayed on my SDR application's
waterfall display.

Many times I have been engaged in a QSO only to have someone CQ'ing on
CW drift across my existing QSO.  Anyone who operates satellites has
probably had this happen to them many times.  Sometimes myself or
others in QSO may try to tell the CW operator "Hello - QSO in
progress" but it is apparent they are not hearing us.

My question is, does it make sense for people using CW on the
satellites to have their receiver set to USB?  Do some operators do
this?  If listening on a VFO with USB and had your transmit VFO set to
CW, would this help make it easier for CW ops to know when they have
drifted into an existing voice QSO?


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