[amsat-bb] Re: doppler.
k1uxbma at comcast.net
Sun Sep 2 12:14:46 PDT 2007
My husband Nick (K1UXB) passed away last February 3, 2007. He had been a Ham operator since age 15. He was 71 when he passed.
Do you know anyone in Massachusetts (I am in Medford) that needs equipment ? I can send you Model #'s etc. He also has lots of huge antennas here at the house.
Please call if you or anyone you know is interested. He would appreciate the equipment being put to good use.
Please forward this e-mail to contact anyone who would be interested. Thanks.
-------------- Original message --------------
From: "John Hackett" <archie.hackett at hotmail.com>
> Hi All,
> Re: doppler. I've attached K4GMJ's article from the August 1992
> issue of Oscar News. It may be of interest to those, like me, who still use
> old equipment.
> In addition to Maury's notes, I can mention, I have used an NE 567 tone
> decoder IC and a LED as the visual receiver with a simple twin-T audio
> oscillator for the transmitted signal.
> A simple twin-T osc: is better than an NE555 in this application.
> I still operate with the Yaesu 290/790 pair + associated homebrew aerials
> and amps (over 20 years now) and manage quite nicely on VO-52 with
> InstantTUNE. When set up correctly, the signals track perfectly so even with
> "old" equipment it's still possible to adhere to THE ONE TRUE RULE regarding
> I don't tune at all for doppler on AO-7.
> Occasionally, just for fun, I tune manually ... (transmitter and receiver)
> .... to keep the frequency constant at the satellite, however ... be aware
> .... it is *NOT* mandatory to keep the signal fixed at the satellite. Many
> operators still use the manual convention of tuning the highest frequency
> .... (because it has the highest doppler rate).
> This is perfectly acceptable because not everybody is either 1) affluent
> enough to be able to afford the latest all singing, all dancing multimode
> rig ... or 2) not experienced enough to cope with doppler on the uplink and
> the downlink at the same time.
> 73 John.
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