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Re: NO-44 Link Question

Matt, doppler on 2M is only +/- 3 kHz in the worst case, so it really isn't 
necessary to adjust for it all that much.  In fact, if you look at the link 
frequency of 145.827, it's right between the normal "channelized" 
frequencies of 145.825 and 145.830, undoubtedly to accomodate 5-kHz tuning 
rigs.  So if you use 145.825 up/145.830 down for the first half of the pass, 
and 145.830 up and 145.825 down for the last half, you should be fine. 
Don't put the 847 in SAT mode:  just program up a group of memories with 
corresponding up- and downlink frequencies, and switch thru them manually 
during a pass, or leave it on 145.827 for the whole pass:  it probably will 
do just fine.

George, KA3HSW

----- Original Message ----- 
From: "Matt Bennett" <kaisermuche@yahoo.com>
To: "Charles R Reiche" <charlieray@optonline.net>
Cc: <amsat-bb@amsat.org>
Sent: Saturday, July 16, 2005 11:10 AM
Subject: Re: [amsat-bb] NO-44 Link Question

> Charles,
> 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
> something?
> Thanks for the help all,
> Matt
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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