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Doppler adjusters



About 8 of us experimented with downlink vs uplink frequency adjust using 
O8 and
O7 many years ago.  The Japanese initially recommended that the uplink  on FO12
be adjusted, and recanted later on.

I'm referring to LOW orbit birds only!!

Our experiments determined that with two people on frequency, it didn't make a
bit of difference.  With three or more, and we did this many times, it was 
BETTER
to adjust the frequency on receive.  Remember, everyone's doppler is 
different, unless
two of the stations happen to be in a position for the same rate of change.

We finally convinced our then president, Vern Riportella, after months of 
discussions,
ON THE AIR, remember we had no computers, that the receive adjust was best.

Also remember we had no (or rarely) radios that would accomplish automatic 
tuning.

Vern did a great deal of research, (as stubborn as he was), and I'll dig 
out the article
he wrote in an AMATEUR SATELLITE REPORT ~1987...and I'll put it on my website..

This doppler thing has been kicked around now for about 20 years, ad 
nauseam, and I
will not get into banter...Just my vote.

I have a "one go up, the other go down" radio, but that feature will be 
disabled
for AO7...



            73, Dave wb6llo@amsat.org
                    Disagree: I learn....

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