[amsat-bb] CW from an FM HT [was: VO-52 underused bird]
John Mock KD6PAG
kd6pag at amsat.org
Wed Oct 25 21:21:32 PDT 2006
> Key the PTT line of your UHF FM transmitter for a CW uplink. Turn the
> mic gain down or remove the mike all together.
> It will chirp a bit, but it can be copied.
If your HT does odd splits and has wide coverage, you might be able to reduce
or eliminate this. Generally, the VFO has to switch from receive to transmit
by the amount of the IF. That's probably where the chirp comes from. I have
not done this experiment with a service monitor to see exactly what happens,
but you might try an odd split such that the RX frequency has been shifted by
the IF frequency (you might have to try both +/- to see which works for your
rig). Then when you key the rig, the VFO doesn't have shift very far (if at
all) and that might make the chirp go away. If you try the experiment, please
let me know.
-- KD6PAG (Networking Old-Timer, Satellite QRPer)
[Note: If i'm in your address book, please replace 'qsl.net' with 'amsat.org'.]
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