Even though APRS is over 30 years old, there are a significant number of threads on getting beaconing working on a given device and, of course, I have found this very difficult. So I am writing this to help someone add yet another opinion to their lengthy search.

APRS is magic, and confusing. It is packet radio using AX.25 protocol over a simplex FM 2m frequency, and is often referred to as Analogue APRS, despite the packet element meaning it is digital. This is to differentiate it from DMR APRS… And AX.25 sounds a lot like a fax handshake.

After my first SOTA activation with a Baofeng, I bought an Anytone 878 UV II Plus as my main HT. It should be a little better than the Baofeng in terms of FM synthesis and reception, it is a DMR radio (which I have barely learned how to use), and it does both analogue and DMR APRS, both as beaconing and SMS. Ergonomically the 878 is a little fat (I think chocolate bar is easier to carry than apple), and I actually really prefer the monochrome LCD on the Baofeng or older radios, they are much easier to read in daylight, and also can be read without the backlight on. The radio has performed really well, I think my longest contact was about 60 miles from Schiehallion (GM-CS-005) to Allermuir (GM/SS-171), 878 to 878 and I was using a Smiley 1/2 wave whip.

APRS to SOTA is a service by which you can send an SMS over APRS to spot your activation. Generally if you spot using your phone, you will appear on aprs.fi via some other system, but using the APRS2SOTA you can spot yourself when you don’t have cell service. To do this, first you need to set up your 878 for basic APRS functionality, then register your callsign with the APRS2SOTA system. To start with, make a channel on the 878 for your local APRS frequency, make it simplex, I tick a couple of other boxes like ptt-prohibit and APRS-RX and APRS-mute (this keeps it from making constant chirping sounds if you are monitoring APRS). Then, in the APRS settings you need to make sure a couple other things are set. Your SSID is -7 if pedestrian, but HERE is the full list. I keep the fixed beacon off, otherwise your location will not represent where you are. I keep the beaconing interval off since you can change that easily on the HT. Symbol and map icon are how you appear on the map, the ones I have show me as a running person. Digipeater path has no punctuation or spaces, this specifies how many jumps you get over the air, and honestly I don’t understand this, since the goal for me is to hit an iGate and get my data on the internet. Tick boxes to the right are all about what you receive when tuned to the channel. Here in Arizona this can be very busy.

Next, go to the APRS2SOTA site HERE and follow the instructions to register. Basically you send a short email with your callsign to the admin, and he adds you to a list. In my case I had two separate emails for KK7BCO and 2M0TFF. When you are on your summit I would recommend writing out your message on paper, since you will be using good old T9, and the 878 times out if you are too slow. I have not found a setting to change this, and there seems to be no way to save a template or edit a sent message on the Antone. Your message will contain
<Ass/Ref> <Freq> <Mode> [callsign] [comment]
and the order of things can change :
<Ass/Ref> <callsign> <Freq> <Mode> [comment]
<callsign> <Mode> <Freq> <Ass/Ref> [comment]
<Mode> <Freq> <callsign> <Ass/Ref> [comment]

The brackets are not part of a message. The last one I sent was:
W7A/AW-011 18.149 SSB KK7BCO, then you go to the next screen and write SOTA, then send. That is it. No receipt confirmation. But it seems to work well.

APRS to SMS sounds amazing, but the system does not work with the 878. For more info you can go to smsgte.org

APRS beaconing is fiddly. I even went as far as building an iGate here in the shack, using a Raspberry Pi and an RTL-SDR.

To get beaconing working, you need to save a channel with the APRS region frequency (I have one for APRS USA and one for APRS UK). Beaconing seems to only work if the APRS channel is active as the “big text” VFO on screen, and then go to the APRS menu and set the interval to something lie 120″. I planned to write out a bigger explanation of what does and doesn’t work, but my 878 is currently on the workbench as it stopped turning on. More on this later.

---

Filed under: blog - @ September 23, 2024 6:37 pm