[amsat-bb] PSK31 Satellite Transponder works! (go Full dux)

Robert Bruninga bruninga at usna.edu
Sat Oct 17 14:46:42 UTC 2015

One more thing to multiply the fun of PSK31 on PSAT,  is to use K0SM's
pre-compensating PSK31 uplink:

Which solves two problems.
1) It solves Doppler (for everyone that sees your signal in any decoder)
2) It lets any user operate fulldux with any other PSK31 client.

Fire up ten meter PSK31 (on 28.120 MHz) and see the downlink on 435.350 MHz
during passes.

But even without the special uplink software, just transmit
HORIZON-to-HORIZON and someone will be at a low doppler-change position
relative to the satellite and will be able to decode you.


On Fri, Oct 16, 2015 at 3:03 PM, KO6TZ Bob <my.callsign at verizon.net> wrote:

> Bob,
> I was just on the 1820u 16Oct15 pass.  10m was high in noise, so the down
> link was hard copy of my own signal.  I only saw one other Doppler
> corrected station (vertical PSK signal) just before LOS. Could not display
> the call sign.
> A couple of hints to successful contacts:
> 1. Do not correct for Doppler by shifting the frequency on your 10m radio.
> 2. Use the Doppler PSK program, allow it to correct for Doppler by
> shifting the PSK-31 frequency.
> 3. Update the TLE's in the Doppler PSK program (copy / paste)
> 4. Once you are able to see your signal on the down link, NEVER stop
> sending until the end of the pass.
>    "Homestead" that frequency.  Just switch from CQ to the QSO sequences
> for a contact.
> 5. Look for other stations somewhere in the VF pass band.
> 6. This procedure is different than working PSK-31 on HF.  So is the power
> level.
> > ON4HTI... will be participating in the... SCR,
> > and we always do a lot of PSK... on 10-15-20m
> Don't forget to listen to the PSK31 downlink on PSAT (NO84).  Its FM
> downlink is the audio copy of everything the satellite hears on the normal
> 28.120 MHz ten meter PSK31 terrestrial hangout.
> And of course since the downlink (FM) adds no doppler, most signals come in
> just fine and can be decoded by any PSK31 clients.
> AND of course, being full duplex, it is fun to be transmitting to EVERYONE
> in the passband at the same time you are seeing EVERYTHING everyone is
> saying.
> Try it...
> http://aprs.org/psat.html
> Bob, WB4aPR
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb

More information about the AMSAT-BB mailing list