[amsat-bb] 9600 baud packet tests (ISS and PCSAT)

Robert Bruninga bruninga at usna.edu
Mon Dec 8 10:00:43 PST 2008

Amusing anecdote of a day-in-the-life of a ham:

I Just saw this on AMSAT-bb:
> I managed to get digipeated via the 9600 
> system during the 10.52utc UK pass.

Ah ha!  Now that explains my morning!:

This morning as we prepare to restore PCSAT for operations when
it comes into full sun, I tried to logon as usual.  The logon
proceess went OK, but seemed "different" than usual.  Then I
realized I had logged on accidently via the UHF uplink and at
9600 baud!  (because the radio was accidentally left in 9600).
I have never used that login technique before in 7 years of
operating PCSAT.

SO I thought, wow, that was nice....  So I'll just send the
first most important restoration command and see how this
goes... That first command is always "00110111" to turn off the
two spare UHF receivers which are a constant drain on the
battery and why Pcsat cannot remain power positive without help.

The link seemed to fail, and I began to notice lots of retries
on my end.....  Duh...  Turning off the 9600 baud UHF backup
receivers when that's what I used to connect with was not the
smartest thing to do.

Anyway, I got re-connected on 2m and 1200 baud and proceeded to
turn off additional loads and beacons.  But I was still hearing
an occasional 9600 baud burst, and couldn't figure out what I
had left on. 

So now I realize the 9600 baud bursts I was hearing was not from
PCSAT but from ISS.  And since the report above says they were
on 145.800, probably I was hearing them from another radio in
the shack that is always monitioring the ISS downlink on .800.
I just checked Instantrack and sure enough, ISS and PCSAT were
in view at the same time.

This will be fun.  I suppose we could turn on one UHF 9600 baud
link on PCSAT if anyone wanted to play with it.  PCSAT can cross
digipeat from 1200 to 1200, 1200 to 9600 or 9600 to 1200 or from
VHF-to-VHF or UHF-to-VHF.  We just have never found much more
use for it other than the usual simplex 145.825 digipeating.  SO
much simpler to explain that way.

Bob, Wb4APR

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