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RE: RE: Eagle



> If the bird is FM, then it is much easier to have the higher band be
> the downlink.  It is easy to tune for doppler by ear on the downlink
> (tune for best quieting) and let the satellite receive 
> capture effect handle
> the uplink doppler.  I found it was much more difficult to 

I disagree here.  If the satellite has a decent AFC, you can get away with
only one or two Doppker corrections on the uplink.  Also, 70cm Rx is quite
critical, and a lot of newbie satellite stations get poor results (the
leading cause of alligators).  Not to mention the increasing 2m QRM
problems.

Just about everyone down here found SO-35 in Mode B was by far the easier
mode to work.  Uplink Doppler wasn't that much of a hassle, and those trying
it with "marginal" antennas could use higher power to compensate (something
the satellite can't economically do).  Also a lot less alligators...  One
frustration here with UO-14 is the number of people who call CQ, but can't
hear the downlink.  Mode B largely solves this problem.

> get into Mir's
> 70cm repeater, for example, because of the need to doppler-match the
> uplink for the station's receiver.  Computer control is pretty much
> required if the upilnk is on 70cm.  (yeah, I know lots of 
> folks do it by
> hand, but let's not push the walk-and-chew-gum-and-tune envelope)

With a decent AFC (e.g. SO-35, which was very good), one can work the first
half of the pass at - 5 kHz, and the second half at + 5 kHz, no dramas.

> But, there is a price to pay for ease.  The pollution we get on UO-14
> from the unlicensed 2 meter stuff down south makes operating nearly
> impossible at times.  I'd rather fiddle with the knobs more, 
> and fight RF
> pollution less, if I had to make that tradeoff.

As I said, I don't find it that much fiddling, and I used to _routinely_
work SO-35 from trains and streetcars (ref:  http://vkradio.com/sat.html).
Heck, I've even worked it while driving and using an Icom T81A (eeeek!).
Certainly not what I'd call excessive knob twiddling.

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