[amsat-bb] Making the transponder sats as easy as the fm birds

[Burns Fisher]

On Sat, Apr 14, 2018 at 12:43 PM, Vince Fiscus, KB7ADL <vlfiscus at mcn.net>
wrote:

> At 12:29 PM 4/14/2018 +0000, Paul Stoetzer <n8hm at arrl.net>wrote:
>
>> The general guidance in the early years of operating linear transponders
>> was to adjust your transmitter to maintain a constant receive frequency.
>> Experience with the Mode J transponder on FO-12 caused the gudiance to be
>> updated to tuning the higher of the two frequencies. See the Sept 14, 1987
>> Amateur Satellite Report for more details (
>> http://www.ka9q.net/asr-1987.pdf).
>>
>
>
> I've always tended to adjust the uplink to the satellite, even
> on mode J.  Never been chewed out for doing it that way though.
>
> My question,  for OM's doing computer control of their rigs. Is the
> software following the rule, or is it adjusting both uplink and
> downlink simultaneously?
>

You say "Is it following the rule?".  As Paul said, the original "one true
rule" of adjusting only Rx changed to adjusting the highest frequency
frequency, but now (see Gould Smith's book, Appendix A) adjusting both is
common if you have computer aided tuning.  Both MacDoppler and SatPC32 can
adjust both in this way (although MacDoppler can certainly be set to only
change one frequency).  I don't think that is in opposition to any rule.
It is just an update of "The One True Rule".



>
> I've always been curious about that.
>
> Still using InstantTrack here.  :-)
>
> KB7ADL
>
>
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