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Re: 9600 Baud Pacsats/Portable?

> I need expert opinion.  See question at end...

I'll try.  :-)

> > In preparing for a student Lab, tonight was my first try at receiving the
> > 9600 baud pacsats from a Mobile...
> What I see are the following UI packets QST, HITVAR, BBSTAT, TLM, PBLIST,
> STATUS and 8 stations were in the PBLIST packets.  All of these packets
> except for the TLM packets contained meaningful TEXT.  But NO packets
> during the eitire 6 minutes contained ANY text or data in them that looked
> like messages, or portions of files.  I saw NO packets other than these
> standard UI frames.  (Only the TLM frame was ascii gyberish as expected).
> I even went to KISS mode.  Still, only the UI overhead and telemetry
> packets, nothing that looked like portions of files or messages.
> Is there a PID problem here?  Is the data itself transmitted with a
> non-standard PID?   Does the PID filter work in KISS mode? Or
> do I have to have a TNC that can accept ALL PID'S?

You don't need to filter PIDs, nor do you need to place your TNC in KISS
mode to monitor pacsat downlinks with a dumb terminal.  If fact if you do,
you'll only make matters worse.  Keep the TNC in "normal" mode, and there's
nothing you won't see.

Most of what you see, however, will be "gibberish".  Most text messages
passed through pacsat satellites are compressed, so even if you catch a
station downloading one, you won't see any meaningful text except for a
few strings in the pacsat file header that forms the beginning of every
file stored on a pacsat satellite.

At 9600 baud, stuff flies up the screen pretty quickly.  :-)

73, de John, KD2BD

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