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GMRS: GPS Location and Texting...


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Now that the FCC has allowed GMRS to have the ability for the “transmission of limited data applications such as text messaging and GPS location information”, is anyone using such features?

 

Is there a protocol that has been standardized, similar to APRS, or is it left to each manufacturer to have their own protocol? (Hopefully there is a standardized protocol.)

 

Anyone actually even using these features? Are there any GMRS transceivers on the market yet taking advantage of this?

 

Hmm. Wondering if this could be used over linked GMRS networks as well?

 

Just curious...

 

Thanks.

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I do remember something in the lines of GPS, and possibly short data bursts but never really looked into it. I can however tell you with the most recent release of the all New Motorola T800 is cellphone friendly inviting possible vendors to step it up! The T800 connects via Bluetooth or WiFi Not sure but works with transmitting GPS location via application(App) on your Smartphone. I’m quite sure this is where companies like Motorola and Garmin are leading the pack in possibilities of next generation possibilities. No need for long extended data bursts, just a squabble here and there. I’m all in for Data via Repeater use due to large Hunting parties and possibly search and rescue.. GPS has allot of advantages versus disadvantages from my standpoint, but to each their own we all have our own opinions on the subject!

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Now that the FCC has allowed GMRS to have the ability for the “transmission of limited data applications such as text messaging and GPS location information”, is anyone using such features?

 

Is there a protocol that has been standardized, similar to APRS, or is it left to each manufacturer to have their own protocol? (Hopefully there is a standardized protocol.)

 

Anyone actually even using these features? Are there any GMRS transceivers on the market yet taking advantage of this?

 

Hmm. Wondering if this could be used over linked GMRS networks as well?

 

Just curious...

 

Thanks.

I've been learning about APRS and would love to have something like it widely used on GMRS/FRS.   It would make things a LOT easier with emergency community coordination that I try to work in.

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In the Los Angeles area the only thing I have been able to hear are constant digital signals. I am not sure if it is someone jamming repeaters or something else.

 

When I monitor with my SDR, the waterfall shows the signals occur on several of the channels simultaneously. Anyone else experience this?

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In the Los Angeles area the only thing I have been able to hear are constant digital signals. I am not sure if it is someone jamming repeaters or something else.

 

When I monitor with my SDR, the waterfall shows the signals occur on several of the channels simultaneously. Anyone else experience this?

 

You're probably seeing the POCSAG transmitters on 462.800 MHz appear on 462.600 MHz and 462.625 MHz. Those are two repeaters (Wilson and Harvard, respectively) getting jammed. It's been going on for several months and is heavily impacting usability of the VNC600 repeater in Ventura County. It's not 24/7, but goes for several hours at a time. Seems to be the result of a squabble between Dennis Doty and Kevin Bondy.

 

Someone is running MOTOTRBO on 462.550 MHz, but it's rarely active. I think it comes from Saddle Peak, but it's so infrequent I can't do any research on that.

 

Aside from those, I'd expect a SDR in Los Angeles to get some nasty front-end overload or intermodulation products. SDRs do not have particularly robust front-ends, and some compromise between sensitivity and selectivity is needed to find a proper LNA gain setting. None of those signals I mentioned here don't really have anything to do with this thread's topic, so those should be discussed in a different thread.

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 I am brand new to GMRS. It would be interesting if we could coordinate and try and see if we can make contact on one of those repeaters. I set my radio up for the Wilson repeater and am going to try it out shortly and see if I can get anyone on it. 

 

Regarding the SDR, yeah, I thought perhaps it could have been harmonic interference, I didn't spend a lot of time playing with it, but the digital signals were mostly on 462.7250

 

I do occasionally here a repeater(?) sending code on 462.625, but I can't copy code (yet) so don't know what the sign is. 

 

73

  

You're probably seeing the POCSAG transmitters on 462.800 MHz appear on 462.600 MHz and 462.625 MHz. Those are two repeaters (Wilson and Harvard, respectively) getting jammed. It's been going on for several months and is heavily impacting usability of the VNC600 repeater in Ventura County. It's not 24/7, but goes for several hours at a time. Seems to be the result of a squabble between Dennis Doty and Kevin Bondy.

 

Someone is running MOTOTRBO on 462.550 MHz, but it's rarely active. I think it comes from Saddle Peak, but it's so infrequent I can't do any research on that.

 

Aside from those, I'd expect a SDR in Los Angeles to get some nasty front-end overload or intermodulation products. SDRs do not have particularly robust front-ends, and some compromise between sensitivity and selectivity is needed to find a proper LNA gain setting. None of those signals I mentioned here don't really have anything to do with this thread's topic, so those should be discussed in a different thread.

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The repeater on 625 was quiet. I called out to the input frequency +5mhz with the tones listed in the page, and with in 60 seconds someone started jamming the Wilson and Harvard repeaters with what sounds like a digital trunking system, or just constant keydowns... Is it correct that digital modes are NOT allowed on the GMRS frequencies except for short bursts for text and location information?

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There's like 6 or 7 infractions at play here (unlicensed operators, non-95 equipment, jamming, retransmitting from another service, unauthorized automatic control, no identification, ...). There's several limitations on data transmission per FCC rules that limit use to short, infrequent, non-voice digital operation in simplex mode. I've only ever heard data once in my 2 years of SDR GMRS monitoring, it's not really in the market yet. I doubt Motorola will make an affordable digital unit, and I doubt any native GPS unit will ever be cheap. I don't see digital taking off, and I don't see any repeater manufacturers willing to add digital repeating capability, since there's no standard.

 

The Wilson repeater identifies with some callsign I can't remember but comes back to an out of state licensee, the Harvard repeater is WPVL308's but is managed by Dennis Doty.

 

I can't hit Wilson or Harvard, their frontends are (intentionally) deaf to keep low-power users from keying the repeater. You'll have to try me on 725 on an afternoon like today. The info isn't on MyGMRS afaik. That channel is pretty busy, and like 600/625 the majority of users disrespect FCC rules (absolutely something to not listen to in public), but unfortunately that's my only shot into LA and we could make it work. I'll PM channel access info, the repeater is open use but this isn't the private subforum.

 

Can you send me IF (I/Q) recordings of the digital signals on 725? I'm not familiar with anything digital on that, besides MDC. See https://www.sigidwiki.com/wiki/User:Kj6psg/Best_Recording_Practices for info on recording IF, it lets me replay a signal as if I'm receiving it live.

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Oh, one problem that we are going to run into is that APRS has a fixed limit of six characters for the call sign.  All GMRS calls are seven characters.  That might cause compatibility issues with existing software, many of such is woefully outdated and unmaintained, even if the standard itself is updated to allow seven.

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Oh, one problem that we are going to run into is that APRS has a fixed limit of six characters for the call sign.  All GMRS calls are seven characters.  That might cause compatibility issues with existing software, many of such is woefully outdated and unmaintained, even if the standard itself is updated to allow seven.

And the wind is taken out of my sails.  :|

 

In the mean time, anyone got any ideas about how to get a radio to use a callsign as a Roger beep, using either fast Morse or ASCII?  Neither sounds particularly rough to listen to...

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There is a new GMRS HT now taking advantage of this feature. I was just released. I believe it is a Motorola (?). I think it allows you to use your iPhone to enter text, sendts ur to radio, then goes out as RF. Sends GPS data to. Kinda interesting. Believe it is $100. Can’t remember if it’s for one unit or two, but interesting it’s starting to developer. Like said, it could be useful for S&R. I have no plans on picking one up myself, but maybe later as better ones elvolve they could get interesting. It doesn’t use APRS, but a protocol similar to it, but for GMRS. I want to say it’s a Motorola Talkabout...

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Oh, one problem that we are going to run into is that APRS has a fixed limit of six characters for the call sign.  All GMRS calls are seven characters.  That might cause compatibility issues with existing software, many of such is woefully outdated and unmaintained, even if the standard itself is updated to allow seven.

That's not a big deal. Just set it up with a Morse or voice IDer. 

I don't think digi ID is a legal ID on GMRS, anyway.

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There is a new GMRS HT now taking advantage of this feature. I was just released. I believe it is a Motorola (?). I think it allows you to use your iPhone to enter text, sendts ur to radio, then goes out as RF. Sends GPS data to. Kinda interesting. Believe it is $100. Can’t remember if it’s for one unit or two, but interesting it’s starting to developer. Like said, it could be useful for S&R. I have no plans on picking one up myself, but maybe later as better ones elvolve they could get interesting. It doesn’t use APRS, but a protocol similar to it, but for GMRS. I want to say it’s a Motorola Talkabout...

Yes, checked it out myself, I like the GPS feature as we use Garmin Rino’s for our expeditions, hikes and hunts. It’s New to the field, but really have no use for it as it’s basically the same thing as the Rinos except with an expanded version of texting and the Rino uses short burst text(Higher End 700 series 755t).. Obviously both Garmin and Motorola are Licensed through the FCC for data bursts.. One other feature that is NOT available is the Repeater Channel feature and that would be huge other than the fact you can NOT use data burst via Repeater anyway 1-22 channels-NO REPEATER Channels. But, In my opinion it’s always good to have Repeater access when out and about..

 

I don’t own a T800 and give it a 4Star just because they took the extra steps and Garmin didn’t in some comparisons of my own choices, but it’s worthy and quite affordable versus the Rinos, so that being said I definitely see a good market for these radios. These are also sold as a pair for @$109 US.. Higher end Rinos sell for $400 US for one unit/radio!! Details are as follows as the user manuals are Not yet publicly available..

 

http://axcesstechnologysource.com/pdf/Talkabout-T800_spec_sheet.pdf

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Now that the FCC has allowed GMRS to have the ability for the “transmission of limited data applications such as text messaging and GPS location information”, is anyone using such features?

Is there a protocol that has been standardized, similar to APRS, or is it left to each manufacturer to have their own protocol? (Hopefully there is a standardized protocol.)

Anyone actually even using these features? Are there any GMRS transceivers on the market yet taking advantage of this?

Hmm. Wondering if this could be used over linked GMRS networks as well?

Just curious...

Thanks.

I have been using Garmin’s rhino series for a few years now, I love the GPS capability of seeing where everyone else is.

 

I haven’t seen any other units other then Garmin’s

 

I hope they choose a system that can be used by everyone, a single system. Like APRS is to ham.

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Garmin Rino radios have been doing so for more than 10 years. The rino's have a map on the screen. When you talk over a frs or gmrs channel your icon appears on the screen of others in your party as long as they are using the same channel. The Garmin Rino's allow you to download topographical maps and city maps. The units are expensive, with the newest models costing more than $ 600.00 each, they include realtime weather radar on screen. They allow apps to be downloaded. You can text to other users. With all of these capabilities the radios are not very good. I believe they are hindered by a poorly designed non-removable antenna. This should be fixed if the Rino moves to the licensed GMRS only and uses a better antenna. The GPS works fine and outdoes other types of portable gps units.

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Garmin Rino radios have been doing so for more than 10 years. The rino's have a map on the screen. When you talk over a frs or gmrs channel your icon appears on the screen of others in your party as long as they are using the same channel. The Garmin Rino's allow you to download topographical maps and city maps. The units are expensive, with the newest models costing more than $ 600.00 each, they include realtime weather radar on screen. They allow apps to be downloaded. You can text to other users. With all of these capabilities the radios are not very good. I believe they are hindered by a poorly designed non-removable antenna. This should be fixed if the Rino moves to the licensed GMRS only and uses a better antenna. The GPS works fine and outdoes other types of portable gps units.

 

The emphasis was on mobile, rather than satnav.  I'd particularly enjoy it if it was a double-DIN in-dash unit with CarPlay, but even a dash mounted display with a transceiver you could stash wherever under the dash (like a combination of a Garmin car GPS and a Midland with the handheld control head) would have me over the moon.

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