Getting position data / APRS from Pi-Star without internet

[rural_radio]

I know you can use a hotspot running Pi-Star to relay position reports and messages send over DMR/YSF/D-Star to aprs.fi, but does anyone know of a way to get that information straight from the Pi when you don't have internet?

I'm working on a portable repeater/digital node for off-grid use, and I'd like to write a script to plot users on a map. I'm mode-agnostic on this, and I'd just use regular APRS over analog, except:
a) you wouldn't be able to have a voice net and report positions on the same radio and channel
b) automated position reporting at 1200pbs with more then just a few users, and you start to step on each other pretty quickly. The digital radios I've used wait until the channel is clear to tx.

 

[vagrant]

I know you can use a hotspot running Pi-Star to relay position reports and messages send over DMR/YSF/D-Star to aprs.fi, but does anyone know of a way to get that information straight from the Pi when you don't have internet?

DireWolf https://github.com/wb2osz/direwolf/blob/dev/doc/README.md I currently use this and a USB SDR for an iGate and push the information over the Internet. Still, I don't see why one couldn't dump it to a log file and then parse that data for your map. Actualy, Xastir XastirWiki can handle the mapping part. I don't use Xastir, but I'm sure someone does and posted a video of install and use. You may need to grab a map before you take the Pi offline. Just set the frequency via DireWolf to whatever everyone is using (repeater input) and have the users send their APRS data when they hit the PTT instead of automatic. (I have not done this myself, but I think this should work. I'm just not sure if it only sends the APRS packet and not voice when set to do that.)

I'm working on a portable repeater/digital node for off-grid use, and I'd like to write a script to plot users on a map. I'm mode-agnostic on this, and I'd just use regular APRS over analog, except:
a) you wouldn't be able to have a voice net and report positions on the same radio and channel
b) automated position reporting at 1200pbs with more then just a few users, and you start to step on each other pretty quickly. The digital radios I've used wait until the channel is clear to tx.

Alternatively, I would think one could use APRSISCE on a Windows OS computer and the proper cable to import that data from a radio or SDR. It should then populate on the map. I have not tried this, so I am unsure. If you set the GPS/APRS capable radios to TX position on PTT, on the same frequency of course, then that should work. This is theory as I have not tried it myself, but in my head I think it would work for your needs.

I think I'll try it myself and then create a simplified PDF for a club meeting. It's always nice to hear curmudgeon's in the back groan. Time itself has a way of dealing with those guys. I'll probably try both because people really groan when they hear "Pi" and you cannot eat it. hahaha good times. Anyways, I'm sure someone has already done this and provided instructions.

 

[rural_radio]

Wouldn't DireWolf require1200 bps or 9600 bps AX.25?

I thought DMR radios sent position reports in LRRP (or a proprietary "digital APRS" on Chinese radios) and Pi-Star just sent the data call out on the net. I assumed it was something similar with D-Star and YSF, but I don't have any experience with GPS in those modes.

Is that not how it works?

As for the mapping, assuming I can get the positions out of Pi-Star in some sort of standard format, I've got that covered. I'll be pushing them into CivTAK.

CivTAK / ATAK

News, Licensing, Support & Download for ATAK / TAK Tools

www.civtak.org

 

[vagrant]

Damn, I really thought there was an option to send an APRS packet beacon when using the PTT. I am unable to find what I thought was there in the latest Yaesu and Kenwood handhelds. That would have been cool, minus the data burst. My brain must be tainted with commercial gear.

Anyways, I obviously misunderstood your request. Still, that data you're looking for seems like someone would have tacked that over on the Pi-Star forums already, or perhaps not if you're asking here instead of the Pi-Star focused forum.

 

[tweiss3]

Damn, I really thought there was an option to send an APRS packet beacon when using the PTT. I am unable to find what I thought was there in the latest Yaesu and Kenwood handhelds. That would have been cool, minus the data burst. My brain must be tainted with commercial gear.

Anyways, I obviously misunderstood your request. Still, that data you're looking for seems like someone would have tacked that over on the Pi-Star forums already, or perhaps not if you're asking here instead of the Pi-Star focused forum.

You might be thinking of the AT-D878UV which does have the option to send either digital or analog APRS position either at the beginning or end of the PTT transmission in addition to a set interval for automatic reporting.

 

[vagrant]

You might be thinking of the AT-D878UV which does have the option to send either digital or analog APRS position either at the beginning or end of the PTT transmission in addition to a set interval for automatic reporting.

Thank you for that. I have a BTech DMR-6x2 and that's probably where I saw that option.

 

[tweiss3]

Thank you for that. I have a BTech DMR-6x2 and that's probably where I saw that option.

Yes, same CPS software and nearly identical firmware.