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Doppler Correction



Hi Guys,

I believe I have a solution that works.
Its just about a low tec as you can get, but addresses the main
problem.

Soundcard Morse decode programs assume terrestrial use.
The AFC can't cope with the large step changes in the audio frequency
which result from the relatively long update intervals in ITUNE.
(approx. 1 second)

The FT847 has tuning steps of 10,1 and 0.1 Hz selectable with Menu
option 2.
Hamscope can show a waterfall display.

Use the waterfall display and manual tuning to keep the received
signal audio as close as possible to the nominated frequency. Takes
one or two frames of telemetry to get your hand tuning in step. I used
0.1Hz steps.

73
John  G7HIA, M3BBX

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