[amsat-bb] SatPC32 CAT control and HDSDR via VSPE

Tom Schuessler tjschuessler at verizon.net
Sun Jan 31 05:55:55 UTC 2016

Hello all,

Not having a good satellite capable radio (Yet) but wanting to dabble deeper
in to our world of satellite communications, I have been experimenting with
CAT control of the SDR program HDSDR via the CAT interface from SatPC32
through the Virtual Serial Port Emulator (VSPE).  VSPE has an option to
create a serial port "Pair" of ports.  In this case, you have to assign one
port of the pair to SatPC32 and in HDSDR's CAT to HDSDR options, you match
the baud rate in HDSDR and SatPC32 but assign the other half of the pair.
Cool thing is it allows HDSDR tuning to affect the frequency listed in it's
downlink window while continue to track Doppler shift adjustments provided
from SatPC32.  This is pretty cool.

Well I have an interesting question which may relate as much to the way
SatPC32's CAT control window works as much as it relates to this Virtual
serial port thing.  The above mentioned ability to tune SatPC323 from HDSDR
works wonderfully on Linear transponder (LSB/USB) modes but not the same on
FM modes like Lilacsat-2, SO-50 and AO-85.  In these cases, shifting the
frequency on HDSDR does NOT change the SatPC32 display and in a few seconds,
HDSDR snaps back to the CAT controlled frequency.  Now the difference of
course in SatPC32 CAT adjustment window is the inability to shift and store
the changes  in frequency, or even just shift them in FM mode like one can
do with Linear sat frequencies.

Am I missing something here or is this just a built in feature of SatPC323
that I will need to work around by providing more appropriate Doppler.SQF
setups that work for me as opposed to somebody else?

Anybody who has played with this please drop me a note or share your
experiences via the list so more people can lear.


Tom Schuessler
2713 Lake Gardens Drive
Irving, Texas  75060
214-403-1464 (Cell)
n5hyp at arrl.net

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