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Re: 9600bps satellites via a Soundcard



Hi Howard,

you wrote:
>Tonight I finally got the proof that you can work even 9600bps PACSATs 
>under Windows with a soundcard and no TNC.
>http://www.g6lvb.com/9600d.jpg

That's GREAT !   and Argh! You are ahead of me!   :-)
I've only gotten the Wisp-SerialIP-Doug'sModem connection running some 
basic KISS stuff back and forth.  I haven't added any of my dsp code yet 
and haven't faked out WiSP with your "real satellite" recording yet.

>It's early days and there's lots and lots of tarting up to do yet: it's very
>messy at the moment. Plus you have to start everything up in just the right
>order!

And we have FOUR programs where we really should only have, maybe, two.
(Ideally we should have WISP talking KISS over TCPIP to a software modem 
instead of Wisp, SerialIP, glue, AGWPE or Wisp, SerialIP, Doug'sModem)
Well, let's get things working first, then optimize later.  I'm still working 
on
my 9k6 dsp code in a modified version of my UO11DEM and pasting in some
TCPIP socket code, but I don't have anything to show working yet.

>Somehow AGWPE is nowhere near as good as my hardware TNC at 
>decoding frames:

I suspect it is AGWPE.  In any event, the end software modem can
always be "upgraded" and that's much easier than upgrading hardware.
The sampling rate on your files is 48000 which should be sufficient for
9600 baud packet.   The nice part about SerialIP is that it will take
the KISS bytes from WISP and feed them byte for byte to a software 
modem and take whatever the software modem sends and give it 
byte-for-byte to WiSP.   The not-so-nice part about SerialIP is the
cost.   

>I played that same WAV file back into the TNC and it was decoding a lot
>more. 
Ah-ha!  See?  The data *IS* recorded in the WAV file, it we just need a 
better soundcard dsp modem for 9k6.  I'm on it, but obviously I don't
seem to have as much free time as you.  :-)

>73 Howard G6LVB

Douglas KA2UPW
dquagliana@aol.com
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