APRS – Making it work

This is my experience of getting APRS to work, all of this was with the last 2 weeks

When I fired up my CHIP, I saw the Amateur Radio folder on Outernet, and in there is APRS (Amateur Packet Reporting System) messages… Now I have held my Amateur Radio qualifications since 1978 (from Australia), and I currently hold the UK Full call License, M0KNC, but, since I help set up old ,now defunct, AX25 Packet Radio network in Queensland, I have not even looked at packet radio.

I HAD to find out how to use this APRS thing on Outernet!

I have always liked digital modes on HF radio, and I have a number of ways of passing email via HF (Shortwave) and one of these is call “PSKMail” and it also has some APRS functionality, where I can send APRS messages. So then I had to work out HOW to get it to go to the Outernet (so I could talk to myself!)

After doing some research, and so YOU don’t have to, I discovered the rules are:

  1. The message should be addressed to “APOUT” – I don’t think this matters a lot, it can be addressed to anyone, but the APRS network owners have set this up as a place for the stray messages to go.
  2. The message must have the word “OUTNET” without quotes in the body of the message. – If you send a message to anyone and it contains OUTNET then the system should see it and push it up to the satellite so it arrives in the APRS folder.

That is it! Easy! When I sent a message on 10.148Mhz from PSKMail that had OUTNET in the content, it was heard by an “iGate” in Austria, and passed through the interwebs until Outernet sent it to the sky, and in just a few minutes there it was, back with me again via Outernet.

VHF ( 2 meters to be exact) is where all the real APRS action happens, what do I need to get going on VHF?

  1. An APRS program for my computer for VHF
  2. A TNC ( or a packet controller
  3. A VHF radio

For 1) I found the cross platform program YAAC ( http://www.ka2ddo.org/ka2ddo/YAAC.html )
For 2) I found the “software TNC” called “DireWolf” ( https://github.com/wb2osz/direwolf/releases )
For 3) I have a couple of cheap Baofeng UV-5R https://www.google.co.uk/search?q=Baofeng+UV-5R these guys (and their cousins) are less than £30 is you look around

I installed the software following the simple instructions on their pages , and made YAAC work as an internet only system ( after a few configuration hiccups!) all I needed was a cable for the radio.
The Audio out of the radio is a standard 3.5mm jack , and the audio in to the mic is a small 2.5mm jack. I discovered that with this radio the PTT is activated by shorting the Mic to the speaker, so one of the cables needed to be isolated or the PTT would be activated. I had an old audio transformer in the junk box, so I used that in the audio out lead. You could use a ceramic capacitor, but, if you use this radio, you have to do something! Just ensure that the grounds are separated :wink:

I plugged it in and YAAC started to show things on the map ( which some people think is all that APRS is good for) and, after learning all about wide1-1, wide2-1 blah, blah, blah I managed to transmit via a local digipeater to an igate and then off to Outernet. Like this:

Address: APOUT
Via: Wide1-1, Wide2-1
Content: hello OUTNET from vhf

The pathway to OUTNET seems a bit “touch & go” at the moment, but it is really easy to get messages onto the bird.
As an added bonus, YAAC can use “outernet” as a “port” for incoming messages… at the time of writing, it does not work with the new “skylark” UI, but does with the old “librarian” … Your mileage may vary!

Here is a photo of the radio, with the map ( note my position “M0KNC” just above the radio) random messages, and the output of the DireWolf TNC. The eagle-eyed amongst you will notice the special RubberBand © connector securing device I have implemented as the small plug (for the audio in) doesn’t stay in by itself :slight_smile:

It should be noted here that, if you have an internet connection and an Amateur License in YOUR country, then you can JUST install YAAC, and ask the developer nicely to let you connect it via the internet, or you could install a phone application that can talk via the internet too ( used to be free but now costs money) . Personally I like to no rely upon my local internet (this the email by HF thing), that is the “fun” of radio :slight_smile:


@neil Thank you for your time. I appericate this. 73, KD9BKH

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Thank YOU for taking the time to reply… I learnt how to do something & thought it best to share…
Now I am looking at what else I can do with APRS… The “tracking” stuff is a bit silly IMHO ( unless you are a fire engine!).
Send email - Check
Receive email - Check (well sort of)
Digipeat via Satellite - Yet to do that! :slight_smile:

what else?

hey @Syed & @Abhishek
there seems to have been no ARPRS data sent from the 25E bird since 03:10
I have been beaconing to OUTNET, so at least some of them should have gotten there :slight_smile:


there has been some connectivity issue with the source feed server I use.

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verified. connectivity issues.

I am going to implement a switchover mechanism.

feed will probably be intermittent over the next 24 hours or so.

No worries :slight_smile:
I will keep beaconing whilst I am awake , every hour or so


I use the AP510 and my android phone with aprsdroid app. It communicates via Bluetooth. My callsign is LB8NG

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Nice @Knut_Kristensen :slight_smile:
I will send you an APRS message just for fun


I am working my way through your instructions - excellent discoveries and something I’ve wanted to do but didn’t have the patience (and also lack of experience with APRS). Have had a Baofeng for quite a while so time to put it to good use.

Have a small glitch so far - cannot get YAAC to save the config after using the wizard. Several attempts but loses all my settings on restart. I am running under Windows 7.

Any thoughts?


I have not had that issue…
I am guessing it doen’t have permission to write the config files.
The YAAC.jar needs to write to \users(your_username) \YAAC If that is not there then that is why it is happening…
You could try running yaac.jar as administrator too

I hope it helps

I reinstalled YAAC and now it saves the config. Even though the previous copy created the YAAC folder under my user name it wouldn’t load the values.

Anyway I can now continue getting set up.



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I decided to try UI-View32 as the APRS client instead, since I have a registered version. I configured it for the APRS Tier 2 network and sent a beacon with OUTNET in the beacon message. I am not configured to transmit RF yet – there isn’t a repeater near enough to hear my Baofeng UV-5R handie talkie.

It wasn’t very long after sending the beacon that I was able to view my message downloaded from I-4 F3.

   KE7KRF>APU25N,TCPIP*,qAC,T2TEXAS:=3155.00N/10909.00W-hello OUTNET {UIV32N}

Since I am a newbie with respect to APRS, is the approach I used somehow contrary to the correct amateur radio protocol?

Would appreciate any guidance on this approach.


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Neil, thanks for the post. Good information there. I haven’t been on packet since the 80s.

I am an APRS newbie too :slight_smile: That said I spent a lot of time digging around and working out the “rules” and I don’t think that sending a message like that directly from your PC by TCP/IP is against the rules :slight_smile:
When you do add RF, beware of what you may “igate”, the settings are always a bit weird. (/me looks around embarrassedly )
You managed to get mapped on aprs.fi ( http://aprs.fi/#!mt=roadmap&z=11&call=a%2FKE7KRF&timerange=3600&tail=3600 ) so you did that right too :slight_smile:

I did a LOT of reading of the official website of the protocol http://www.aprs.org/ and really confused myself :stuck_out_tongue:


Thanks !!

Just wanted to +1 being able to successfully send an APRS packet through Outernet.

I used APRSDroid coupled with a 2m handheld.

For those interested, I sent a message to WXBOT and included “OUTNET” as part of the message. The returned weather forecast showed up on Outernet.

Some interesting potential here for one way communication if you know an individual in a remote location that happens to be monitoring those Outernet APRS packets.

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great idea :slight_smile:
As long as they are in the US though… WXBOT only gives US weather reports :slight_smile:

The potential is huge though if more bots are created.

I have my HF system, located in Winchester (which is remotely controlled when I am away, like now) beaconing on 10.147Mhz with PSKMail.
Since my Outernet RX appears to have fail on Monday ( only a few hours after I left it!) I cannot see if any of the (hourly) beacons are getting to Outernet.
I would appreciate it if someone could tell me :slight_smile: