APRS on MURS

[gman1971]

I believe telemetry and data can be used on MURS, just limited to 2W. So, I was wondering what is required to get started on a stand-alone home tracking APRS setup, without requiring to log on the internet or use ham internet sites, etc, just for the stuff around my property? What kind of radio do I need to make this happen? Can a portable work?, or do I need a particular mobile? Could the EVX-5300/5400 do it? well, provided I run a 10dB attenuator on the TX side of the radio (to keep ERP power within legal 2W limits) 

 

Thanks.

 

G.

[Radioguy7268]

The only company that I know of which still offers a "standalone" GPS for analog emissions is IDA company - www.idaco.com   The stuff works, but it's not a 'cheap' solution.

 

I'd also tell you that if you're heading in that direction - why limit yourself to MURS?  Get a real part 90 license & go for something with some legs. No sense spending for a self contained GPS solution that's only good for a mile or two, and have to deal with trying to integrate it with MURS limited equipment (your EVX radios are still not MURS legal if you're running something with a detachable external antenna - which you'd pretty much need in order to throttle it down to 2 watts.)

 

There used to be a few companies that made a WiFi based GPS solution, where the vehicle would have a GPS antenna & receiver that would collect tracking information throughout the day, and whenever the vehicle returned within the range of the Home Base/Transport Garage - the WiFi would connect & download that day's info.  Not exactly real time, but it did the trick for History Logging. It would also work within a few hundred foot radius if you got the WiFi access point up high enough. Not sure if you could make something like that into a real-time tracking setup, or if there's anyone still making that. I haven't seen anyone trying to re-sell any old turn-key systems via Ebay or anything.

 

There's a few units offered for sale that plug directly into a vehicle's OBD-II port & work through Cellular data at a fairly low monthly cost.

[gman1971]

Hey thanks, certainly a lot of stuff available from that company.

 

I was thinking more of a TNC hooked up to a soundcard or something like that, rather than a full commercial solution.

 

Have considered getting an LMR license too... and that is certainly a possibility. And if going that route I know Motorola has an asset tracking solution with their MotoTRBO stuff...

 

G.

 

The only company that I know of which still offers a "standalone" GPS for analog emissions is IDA company - www.idaco.com   The stuff works, but it's not a 'cheap' solution.

 

I'd also tell you that if you're heading in that direction - why limit yourself to MURS?  Get a real part 90 license & go for something with some legs. No sense spending for a self contained GPS solution that's only good for a mile or two, and have to deal with trying to integrate it with MURS limited equipment (your EVX radios are still not MURS legal if you're running something with a detachable external antenna - which you'd pretty much need in order to throttle it down to 2 watts.)

 

There used to be a few companies that made a WiFi based GPS solution, where the vehicle would have a GPS antenna & receiver that would collect tracking information throughout the day, and whenever the vehicle returned within the range of the Home Base/Transport Garage - the WiFi would connect & download that day's info.  Not exactly real time, but it did the trick for History Logging. It would also work within a few hundred foot radius if you got the WiFi access point up high enough. Not sure if you could make something like that into a real-time tracking setup, or if there's anyone still making that. I haven't seen anyone trying to re-sell any old turn-key systems via Ebay or anything.

 

There's a few units offered for sale that plug directly into a vehicle's OBD-II port & work through Cellular data at a fairly low monthly cost.

[kipandlee]

argentdata  has some  APRS Packet Radio stuff reasonably priced and a pretty good selection of radio compatible cables giving a few different options     https://www.argentdata.com/catalog/index.php?cPath=22

[gman1971]

argentdata  has some  APRS Packet Radio stuff reasonably priced and a pretty good selection of radio compatible cables giving a few different options     https://www.argentdata.com/catalog/index.php?cPath=22

 

THANK YOU very much!!

 

G.

[kipandlee]

you are very welcome 

[jct0002]

But you have to do the legwork on the GPS source etc.

 

https://byonics.com/tinytrak4/

 

Cheers,

C

[WROZ250]

A little late to the topic here, but I think the OP needs to reread Part 95. 

While GPS 'data' is legal on MURS and GMRS, 'APRS' (as most know it) would not be legal due to the nature of how APRS functions.  Yes, it's splitting hairs, but as they say, the Devil is in the details.  I'm pretty sure the data transmission rules were written as to prevent the use of APRS for exchanging GPS 'data' over MURS and GMRS.

As always, to each their own.
 

[Lscott]

5 hours ago, WROZ250 said:

A little late to the topic here, but I think the OP needs to reread Part 95. 

While GPS 'data' is legal on MURS and GMRS, 'APRS' (as most know it) would not be legal due to the nature of how APRS functions.  Yes, it's splitting hairs, but as they say, the Devil is in the details.  I'm pretty sure the data transmission rules were written as to prevent the use of APRS for exchanging GPS 'data' over MURS and GMRS.

As always, to each their own.
 

I haven’t really used APRS so could you expand on what you see as an issue with using it on MURS, or GMRS/FRS?

[WROZ250]

2 hours ago, Lscott said:

I haven’t really used APRS so could you expand on what you see as an issue with using it on MURS, or GMRS/FRS?

In a nut shell, part 95 states Digital GPS data (Think DPRS, which is GPS and SMS data using digital modulation as used on DMR systems).  APRS is analog data (Audio Frequency Shift Keying).  Additionally, GPS data cannot be sent through a repeater, can not be 'digipeated, and (apparently) can only be used on handheld radios with integrated antennas.

'Digipeating' is how APRS extends the range of sent data.  Each receiving radio can be configured to repeat data packets not sent to them specifically.  Again, this is not allowed on GMRS/MURS.  You send it and whoever gets it (if anyone) that's it.

Admittedly, this seems like splitting hairs, but that seems to be the rule as written.

 

[Lscott]

44 minutes ago, WROZ250 said:

In a nut shell, part 95 states Digital GPS data (Think DPRS, which is GPS and SMS data using digital modulation as used on DMR systems).  APRS is analog data (Audio Frequency Shift Keying).  Additionally, GPS data cannot be sent through a repeater, can not be 'digipeated, and (apparently) can only be used on handheld radios with integrated antennas.

'Digipeating' is how APRS extends the range of sent data.  Each receiving radio can be configured to repeat data packets not sent to them specifically.  Again, this is not allowed on GMRS/MURS.  You send it and whoever gets it (if anyone) that's it.

Admittedly, this seems like splitting hairs, but that seems to be the rule as written.

 

Yes, there are some very specific restrictions on data transmissions on GMRS/FRS. I posted about that in another thread about non-removable antennas.
 

However it’s specifically allowed on MURS. Of course the rules also don’t allow repeater operation so that question can’t even come up, and limited to 2 watts. But data transmission is allowed on MURS. Apparently a variety is mentioned in the rules. MURS was created as a Multi Use Radio Service, not primarily, or strictly used, for voice communications.

https://www.law.cornell.edu/cfr/text/47/95.2731

While APRS can’t be relayed through a repeater it can still be used on a local basis, like for example search and rescue work, in a limited geographic area using simplex communications. At least that’s how I see it.

[WROZ250]

10 hours ago, Lscott said:

Yes, there are some very specific restrictions on data transmissions on GMRS/FRS. I posted about that in another thread about non-removable antennas.
 

However it’s specifically allowed on MURS. Of course the rules also don’t allow repeater operation so that question can’t even come up, and limited to 2 watts. But data transmission is allowed on MURS. Apparently a variety is mentioned in the rules. MURS was created as a Multi Use Radio Service, not primarily, or strictly used, for voice communications.

https://www.law.cornell.edu/cfr/text/47/95.2731

While APRS can’t be relayed through a repeater it can still be used on a local basis, like for example search and rescue work, in a limited geographic area using simplex communications. At least that’s how I see it.

MURS rules do seem more relaxed as compared to GMRS/FRS when it comes to data.  It seems that APRS could be used, but strictly in a peer to peer mode.  Store/forward, which is essentially what digipeating is, would also have to be turned off.  Again, digipeating is normally active on all APRS devices.  It is one of the key features and what makes it so useful.  UserX who is out of range of UserZ, can still get the information via UserY, who is in range of both UserX and UserZ, by relaying their respective data.

There is admittedly a lot of 'interpretation' involved here where the rules are concerned. 

However, fundamentally speaking, for all of the hassle disabling what is IMHO, some of the key features of APRS, combined with connecting APRS modems to a hand held, it seems like a waste of time.

By the rules disallowing store-forward on data (APRS or other), they have, IMHO, overlooked the usefulness of location data in these services in, as you mentioned, search and rescue operations.  Is it still useful? sure, but not as much as it could be if they allowed store-forward.


 

[Lscott]

3 hours ago, WROZ250 said:

MURS rules do seem more relaxed as compared to GMRS/FRS when it comes to data.  It seems that APRS could be used, but strictly in a peer to peer mode.  Store/forward, which is essentially what digipeating is, would also have to be turned off.  Again, digipeating is normally active on all APRS devices.  It is one of the key features and what makes it so useful.  UserX who is out of range of UserZ, can still get the information via UserY, who is in range of both UserX and UserZ, by relaying their respective data.

There is admittedly a lot of 'interpretation' involved here where the rules are concerned. 

However, fundamentally speaking, for all of the hassle disabling what is IMHO, some of the key features of APRS, combined with connecting APRS modems to a hand held, it seems like a waste of time.

By the rules disallowing store-forward on data (APRS or other), they have, IMHO, overlooked the usefulness of location data in these services in, as you mentioned, search and rescue operations.  Is it still useful? sure, but not as much as it could be if they allowed store-forward.


 

Makes sense to me.

I wonder if a packet network would be allowed? I’m thinking about packet routing if that would be considered a store and forward operation.

[WROZ250]

4 hours ago, Lscott said:

Makes sense to me.

I wonder if a packet network would be allowed? I’m thinking about packet routing if that would be considered a store and forward operation.

Just a thought, but perhaps a way around the store forward over the air limitation, would be for a base station (or similar S&R EOC setup) could receive and relay the data to rescue personnel via an alternate (non MURS) network?

Dunno, bit of a PIA to deal with it all from my perspective.  But...

 

[gman1971]

Thanks for the heads up.

 

G.