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Re: AO-27 Freq, and my first AO-27 QSO



    436.805 - 145.845
    436.800 - 145.850
    436.795 - 145.850  middle of pass
    436.790 - 145.850
    436.785 - 145.855

Please do NOT attempt to correct for doppler on AO-27 uplink.  The satellite
has a wideband receiver and takes care of that for you.  When one does so,
it increases (doubles??) the amount of bandwidth that AO-27 consumes on the
uplink in the 20 KHz wide 2m space sub-band. It is required for UHF uplinks,
such as the MIR/SAFEX repeater [SK??], but not for AO-27.

AO-27 downlink was originally 436.800 but the crystal has drifted enough that
this could no longer be maintained and i believe 436.973 is now nominal.  I
also only occasionlly use 436.785, mostly because so few people are on that
late in the pass that i don't notice that it's time to switch the receive
frequency down 5 KHz.  I'll have to try that next time and see if it helps.

>>  Upink doppler correction on AO-27 is unnecessary and wasteful.  <<

Hopefully, that will also be true of the new birds scheduled for launched 
this in a couple of months.

It is *much* better, if you had dual-receive capability, to be listening 
on UHF while transmitting on VHF.  Even if one doesn't hear one's own
downlink, one may be able to hear that someone else who has a stronger 
signal and back off until that station finish transmission.  That's why
an FT-51 is a better rig to get than an FT-50 if you're starting out (and
can afford the difference).

I hear Wendy (KC2BZJ) fairly often out here in California and hope to hear
both you on the weekdays at least.

                                -- KD6PAG
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