I’m a frequent user of APRS (try not to hike without it) and try to use it at home, as well, to watch for activations. This morning I was setting up a filter on my APRS-IS connection and wondered if there was a symbol specifically for SOTA activations. Turns out there is!

Version 1.2 of the APRS Symbols and Overlays defines a Summits on the Air symbol as S; (the ; symbol with a ‘S’ overlay).

Other portable symbols are:

/; = Portable operation (tent)
; = Park or Picnic
F; = Field Day
I; = Islands on the air
S; = Summits on the air

It would be nice if those using APRS with their activation could use this symbol as it would make it easier to find you on the map!


It’s nice but I prefer Sn rather than the S; code. The S; code looks like a picnic table with an S overlayed. The Sn symbol is a red triangle (similar to red peak) with S overlay.

I wonder if software will start supporting unique symbols for symbols with overlays. That way we could make a specific SOTA symbol.

Thanks for pointing this out. Great idea.
I’ve been playing with the various symbols on my FT-1D. (There is a ‘user’ symbol that can be set using 2 characters.)
I have to agree that the S; symbol is not very compelling and Sn looks a lot more like SOTA activity.

73, Bob K0NR

I believe the latest spec allows for different symbols to be used instead of the original with the overlay. With that in mind, I’ll ask if that functionality is available in Xastir (my current go-to) and if it is I’ll try to design the SOTA symbol specifically for S;. Perhaps if we can make that happen other software will follow.

I know Eric. I would love that. I emailed the administrators of APRS about it and it doesn’t sound like the like to make changes.

Charlie NJ7V

Just getting around to looking at this more closely but just how do I accomplish getting the Sn symbol on the aprs.fi map for my target summit activation location?

Logically, I guess I would have to set the target summit location beforehand by logging in to a APRS-IS server, send the command for the SOTA symbol (“Sn”) and associating that symbol with the target summit lat/long.

What are the commands necessary to log into the APRS-IS server and set the summit location with the Sn symbol?

Thanks, Guy/n7un

Well, you’d use an APRS client of some kind. It’s likely best to use an APRS-capable HT and just set your symbol to “S;” when you get to the summit and include your frequency information in your status text.

What changes did you request and who did you send the request to?

Since “S;” has already been designated the SOTA portable operations symbol we just need to work on the clients to support an updated symbol just for that combination. I need to take a few minutes (maybe today?) to sit down and send a message to the Xastir-devel list. I can also include aprs.fi as well.

sent to Robert Bruninga bruninga@usna.edu


"Hi Bob - how would a person go about requesting the symbol definition of Summits on the Air change? Currently the aprs definition site lists SOTA as S semicolon (S;).
Inline image 2
I propose Sn is more appropriate as it is a closer match to the SOTA logo:
Inline image 1

Charlie NJ7V"


"I hate to make changes. Is it possible to scan the entire APRS-IS and see how many people are using the S; now? The S; should show as a green tent with an S overlay, and one could argue that that looks more like the SOTA symbol above than the triangle.

Maybe we have to ask lynn or FINDU to search for symbols. I believe FINDU has such a CGI.


Yeah, I can understand that. Let me see if I can get a symbol (artwork) squared away to use with “S;” and see how that goes.