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Beginners and operation

Att köra PSK31 via PSAT NO-84

Scott, K4KDR har gjort några bra noteringar om hur man kör PSK31 via PSAT:

 

Hi everyone.

If you would like to make some satellite contacts using a digital mode that
doesn't require linux, it turns out that the PSK31 transponder on PSAT
(NO-84) works very well.

A few days ago I posted that I had successfully used PSAT's PSK31
transponder:

http://www.amsat.org/pipermail/amsat-bb/2018-November/070178.html

I had always seen in the documentation that the 435.350 FM downlink from
PSAT transmitted PSK31 and I had even decoded its telemetry beacons using
FLDigi.  However, until a new How-To came out last week, I had never
figured out how to use the 10m USB PSK31 uplink to add my own signal to
PSAT's 70cm downlink stream.

Here is that excellent How-To from 2M0SQL:

https://www.2m0sql.com/2018/10/29/using-the-no-84-psat-psk-transponder/

... and I am making this post to share a couple of additional notes.
Please forgive if this is old news, but it was new to me.

I have uploaded some screen shots to illustrate.  First, please note the
bottom waterfall in this image showing -2- PSK31 streams in PSAT's downlink:

https://www.qsl.net/k/k4kdr//how-to/psat-psk31/fldigi-decoding.png

... the stream at the 310 Hz. mark is PSAT's telemetry beacon, but the mark
at 2369 is a repeat of what I am transmitting on 28.120!

Since the key to this is FLDigi's ability to decode multiple streams at the
same time, it's extremely helpful to SEE each of those streams separately.
In the following image, please note how to enable the left-hand "channels"
browser window in FLDigi:

https://www.qsl.net/k/k4kdr//how-to/psat-psk31/fldigi-view-channels.png

... and this is a matter of personal preference, but I find that the most
helpful display setting in that left-hand window is to label each stream
with the audio frequency it's on:

https://www.qsl.net/k/k4kdr//how-to/psat-psk31/fldigi-freq-view-settings.png

... when you click on any of those decode streams, that selects which
stream appears in the main upper decode window in FLDigi.

So that's the decode side of this.  If you combine that with the
information provided in the How-To by 2M0SQL on how to transmit, we ought
to be able to get some 2-station or even multi-station QSO's logged.

Finally, if you don't have 10m transmit capability -or- even if you only
own an FM radio, this is a digital mode that you can absolutely decode to
enjoy another aspect of one of our long-orbiting satellites.

If you would like to practice using FLDigi to decode the PSK31 signals from
PSAT, here is the audio file that produces the two streams you see in the
screen shots I have mentioned above:

https://www.qsl.net/k/k4kdr//how-to/psat-psk31/psat-psk31-sample-audio.wav

-Scott,  K4KDR

By SM0TGU

Webmaster and member of the AMSAT-SM steering group.

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