SarTopo Offline & APRS

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03 May, 2018 07:46 PM

I see references to sartopo working with APRS, but nothing that really says where to start to make it work.

Very interested in getting sartopo to work especially where there is no internet infrastructure.


  1. Support Staff 1 Posted by matt on 04 May, 2018 09:35 PM

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    Edit the file and add the following:


    After that it will listen for APRS data (text out of a TNC, not KISS format) on attached serial ports. On a saved map, you need to do Add New -> Add Locator, type APRS. The interface is a little odd for APRS since it's designed to work with a number of different tools, but you need a separate locator group for each callsign (not counting -XX SSIDs), so it's easiest if you can use a single team callsign with different SSIDs for each member, inserting the operator callsign into the comments section of the packet if needed.

    Local APRS traffic that doesn't match an existing locator group should show up in a "callsign" folder on your map, to give you a sense of traffic that you're not tracking.

  2. 2 Posted by takeuchi on 05 May, 2018 02:00 AM

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    Thank you so much for the reply... I think this helps, but have a few questions...

    1. I don't see "Add Locator" maybe that's want I'm missing.... Is this a new feature an I'm down level?

    2. If I get a TNC to read the APRS signals, anything I need in the system between SarTopo and the serial port to interpret the signals?

    3. If I am in an urban area, any thing different to use this with the web version of SarTopo or it should work there too? Or should I be pointing to something like


  3. Support Staff 3 Posted by matt on 05 May, 2018 04:23 AM

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    1. For technical reasons, it's only available on saved maps.

    2. No, as long as the TNC is putting out text similar to what goes out over APRS-IS (ie not KISS, sorry, I'm not up on the exact terminology at the moment).

    3. pulls data from the APRS-IS network

  4. 4 Posted by takeuchi on 05 May, 2018 06:33 AM

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    Thanks Matt!

    Found the feature and now working to better understand the APRS-IS technology.

  5. matt closed this discussion on 07 May, 2018 03:38 AM.

  6. takeuchi re-opened this discussion on 08 May, 2018 09:15 PM

  7. 5 Posted by takeuchi on 08 May, 2018 09:15 PM

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    Does anyone have recommendations for a radio for SarTopo / APRS? I was about to get a Kenwood TM-D710GA, but realize it has a serial output - sounds like another point of failure going from a serial port to USB.... Curious if a Yaesu FTM400 with USB port would work just as well?

    Any thoughts on this?


  8. Support Staff 6 Posted by matt on 09 May, 2018 05:51 AM

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    I'm not familiar with that radio. I also don't have time to digest this entire thread, but if there isn't a way to stop the radio from adding line breaks in the middle of a position report, that's not something I see myself handling any time soon. The serial port code is shared with other uses such as FleetSync, and it's all based on carriage-return terminated lines.

  9. 7 Posted by takeuchi on 16 May, 2018 06:30 AM

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    You said "No, as long as the TNC is putting out text similar to what goes out over APRS-IS (ie not KISS, sorry, I'm not up on the exact terminology at the moment)." Everything I'm seeing seems to indicate all the radios to computer interfaces use KISS.

    I'm worried about going for a Kenwood TM-DM710GA for this purpose, finding out that I can only use KISS and it won't work with SarTopo. Am I worried over nothing and people have use this combination successfully?


  10. Support Staff 8 Posted by matt on 16 May, 2018 04:31 PM

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    Most radios support KISS as a mode; it looks like the Kenwood also provides other output formats that SARTopo should be able to read, but I'm having trouble finding sample packet data online that I could plug into my program to verify.

  11. 9 Posted by takeuchi on 16 May, 2018 09:52 PM

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    Just borrowed a Kenwood D700 - I'll tinker with it and report my findings here.....

  12. 10 Posted by takeuchi on 27 May, 2018 06:21 PM

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    I ended up not having luck with the Kenwood TM-D700.

    Purchased a Kenwood TM-710GA and it works perfectly! One key difference I found is a field on the Kenwood software that read "PC Port" and "PC Output" - on the RT Systems software that reads "COM Port Output" that worked perfectly.

    One thing I noticed is to be careful not to go switching the serial cable too much. The PC side and the radio side can get to the point where they aren't talking well... If that happens, rebooting the server on the PC and cycling power on the radio seems to help.

    Thanks - this is now working great!

  13. 11 Posted by takeuchi on 08 Aug, 2018 02:13 PM

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    We had an event locally where we got to tinker with the SAR Topo Offline and APRS - One issue we kept running across is units that weren't tracking or the status freezing. I found it I shut down the browser and the server and restarted everythink it would not only work again but it would seem to catch up with what we weren't seeing while the display was frozen.

    Any ideas that might cause this?


  14. Support Staff 12 Posted by matt on 08 Aug, 2018 11:09 PM

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    Do you know for sure that restarting the server was required, as opposed to just the browser? If it caught back up, that suggests that the server was running fine and the browser was hung up.

  15. 13 Posted by takeuchi on 09 Aug, 2018 02:30 AM

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    I don't - I tried the browser and it seemed to stall - but maybe I wasn't being patient enough... I agree that obviously it gathered the data somehow... So I probably needed to be more patient....

    I also noticed it seemed to update some of my APRS signals but not others... I was running with several different call signs so had 3-4 locators defined... Could that cause issues?

  16. Support Staff 14 Posted by matt on 09 Aug, 2018 03:11 AM

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    Multiple locators shouldn't affect things.

    What version of the jar file were you running?

  17. 15 Posted by takeuchi on 09 Aug, 2018 03:35 AM

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    Running SARTopo Offline version 4039, 05/17/18 04:45:16

  18. 16 Posted by takeuchi on 14 Aug, 2018 03:00 PM

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    Is 4039 OK for this?

  19. Support Staff 17 Posted by matt on 15 Aug, 2018 02:40 AM

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    It should be, I wanted to make sure you didn't have an old version. I'm sorry, beyond that I haven't had time to assess this further yet.

  20. 18 Posted by takeuchi on 15 Aug, 2018 06:32 AM

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    OK - Thanks... Let me know if you find anything....

  21. Support Staff 19 Posted by matt on 18 Sep, 2018 09:31 PM

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    I don't have anything new to report on this, but a significant portion of the location tracking code has been rewritten. So 1) the issue may no longer exist, particularly if you can't replicate it on using APRS-IS locators and 2) when you upgrade the latest offline version, be careful to test the local APRS part as there might be bugs that haven't been found yet (I don't have a lot of testing resources for this).

  22. 20 Posted by mvbanks on 18 Sep, 2018 09:45 PM

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    If I get some time, I will test and provide some feedback.


  23. 21 Posted by takeuchi on 19 Sep, 2018 03:05 AM

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    Thanks Matt! We're going to try things out again in a few weeks at our county fair to track our assets on our fairgrounds.

  24. 22 Posted by pbrunson on 12 Feb, 2019 08:01 AM

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    Question on the APRS tracking settings.

    It shows a marker for each packet and I can set the timeout to change the color. But I end up with a ton of markers per unit.

    How can I limit the number of markers per unit, or just the current location?

  25. Support Staff 23 Posted by matt on 12 Feb, 2019 08:47 PM

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    Can you send a screenshot? It should be showing a single marker for each ID, with a track tail depending on how far the unit moved, not a marker per packet.

  26. 24 Posted by pbrunson on 12 Feb, 2019 08:55 PM

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    Email sent

  27. Support Staff 25 Posted by matt on 16 Feb, 2019 05:10 AM

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    Resolved with Phil over email.

  28. matt closed this discussion on 16 Feb, 2019 05:10 AM.

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