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Re: NO-44 Link Question

Hi Matt,

I have an FT-736R, but I expect the same technique can be used with nearly 
any rig.  The fact that you are working a satellite doesn't necessarily mean 
that you need to use the satellite mode in the radio.  For same-band 
operation, such as with ISS or PCSat, the satelilte software can use 
traditional (Earth-bound) FM repeater mode.  It programs the repeater offset 
for -2 times the amount of doppler, and sets the receive frequency for the 
downlink plus doppler.  Then when you transmit, the rig instantly and 
automatically shifts the right amount to land on the uplink frequency.

FODTrack can handle this, and I expect there are others.


Greg KO6TH


Thanks for the reply. I understand that PCSat is a
digipeater, but I'm wondering how to get around
Doppler, not how to listen to the downlink while
transmitting. At any given moment, the transceiver
will be tuned to receive the downlink signal, but must
be prepared to transmit at a different frequency as
soon as the TNC keys the PTT. Example: With PCSat
approaching, the downlink will be 145.827 +Doppler,
and uplink will be 145.827 -Doppler. The transceiver
must instantaneously switch to the uplink frequency
when keyed up by the TNC, or else the transceiver will
transmit the signal on a frequency too high for that
sat to hear. The 847 won't allow same-band ops or
split frequency offset in sat mode, so how does one
accomplish this with this rig? Am I still missing

Thanks for the help all,

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