[amsat-bb] SO-67 Suggestions

John Papay john at papays.com
Wed Jun 30 10:00:52 PDT 2010

SO-67 is in a mode whereby the uplink audio is
repeated as long as the transmitter is turned on.
If there is no PL on the uplink, repeated audio
will be reduced by about 10db compared to rx noise
when no satellite is in view. SO-67 is being turned
on for 15 minute periods as conditions permit.

If you transmit PL, the repeated audio level will
be 10db higher than with no PL, however the PL tone
level will also be very high.  There is apparently no tone
filtering between the receiver and the transmitter.

Once you stop transmitting with PL, you will hear rx
noise at full deviation.  After 2-1/2 seconds or so,
the repeated noise/audio level will once again be 10db down.

As mentioned in another post, the best way to operate
given this configuration is not to use PL and work with
the low audio.  Since this bird is very strong, low audio
is not a big problem.  If there are signals with PL, the
audio level will jump up 10db so watch your ears.

John K8YSE

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