[amsat-bb] Using a Raspberry Pi (or any linux system) for packet APRS

[Scott]

Hi everyone.

I really enjoy the aspects of Amateur Radio that involve connecting our
radios to a computer.  That includes decoding telemetry from the long list
of cubesats in orbit now as well as digital modes like packet.  It's been
great to have the ISS digipeater back in service, plus PSAT has been
working well lately.

I normally use UISS on Windows for my packet operations but thought it
would be fun to try to find the most simple method of doing the same thing
on linux, in particular a Raspberry Pi.  I know there are linux packet
apps, but I was looking for something as lite as possible that was
point-and-click like UISS.

This is important... please note that this is NOT a turnkey, step-by-step
how to.  But rather, I wanted to share my findings so that anyone
comfortable with linux/Pi basics could install a couple of pieces of
software and edit a few text files.

Since I wanted to demo how it actually works, I recorded a screen session
on my Raspberry Pi.  It's not meant to be fancy and has no audio, but the
"narration" is done with text on the screen so that you can pause the video
at any time you wish to read or take notes.  The video is at:

http://www.qsl.net/k/k4kdr//video/2018-09-02--RPi-APRS-demo.mp4

... and all the files AS I USE THEM can be found at:

http://www.qsl.net/k/k4kdr//downloads/pkt/

... please note, if you'd like to duplicate my little experiment, it's
critical that you do the following:

--determine which audio device connects to your radio & setup a proper
.CONF file for Direwolf

--if you're not using VOX for PTT (i.e., Signalink), then determine which
USB or serial devices keys your PTT & put that in the Direwolf .CONF file

--edit each and every .SH script file & replace my call sign with yours,
plus edit the wording to suit yourself

... so, obviously not as easy as UISS on Windows but for portable use, a
Raspberry Pi might be easier to carry than a full-size laptop.

Final note, while I did the video demo on a Pi, this setup works equally
well on any linux computer as long as you review your Direwolf .CONF file
and all the scripts to make sure they are using syntax that is proper for
your system.

For anyone already familiar with the linux or Pi environment, I hope my
learnings might save you some time.  I know this all sounds complicated,
but it's really not... only a few things to configure and you're up and
running!

I used this setup on a PSAT pass the other day and was digipeated several
times.  Here's a screen shot of findu.com from that pass:

http://www.qsl.net/k/k4kdr//images/2018-09-01--PSAT-Pi.png


I hope this might be interesting to someone.  Of course please contact me
if you give it a try and have any questions.

-Scott,  K4KDR