Ribbit/Rattlegram on GMRS

[Blaise]

I saw the post about Ribbit yesterday, became intrigued, and got lost down an ODFM rabbit hole for a few hours, but then, I loaded the Rattlegram App on two phones, put a phone/GMRS radio in another room, and sent a text message between two phones over GMRS radio.  It was really cool.  I'm addicted.

Links:

https://www.ribbitradio.org/#/

https://www.youtube.com/watch?v=ubPP48ojJ3E

 

Also, anyone have any idea what it might be useful for, so I have an excuse for all this time I'm wasting on a burgeoning new addiction?

 

[WRQC527]

4 minutes ago, Blaise said:

I saw the post about Ribbit yesterday, became intrigued, and got lost down an ODFM rabbit hole for a few hours, but then, I loaded the Rattlegram App on two phones, put a phone/GMRS radio in another room, and sent a text message between two phones over GMRS radio.  It was really cool.  I'm addicted.

Links:

https://www.ribbitradio.org/#/

https://www.youtube.com/watch?v=ubPP48ojJ3E

 

Also, anyone have any idea what it might be useful for, so I have an excuse for all this time I'm wasting on a burgeoning new addiction?

 

Someone started a thread about this a couple weeks ago. Personally, I thought it sounded pretty cool. I don't really have a use for it, but it sounded better than messaging through APRS, which I found to be a PITA. But predictably, quite a few folks here immediately found fault with it and discussed its uselessness. 

[Blaise]

Yeah, I found that post yesterday, and read the discussion.

The app is just a technology demonstrator, to show you can send data easily and quickly with Ribbit.   It works like a charm, too!

I can see pairing this tech with vox mode to set up on-the-go networks with uplink stations miles apart with nothing but cheap HTs and laptops, at the very least...

[WRQC527]

I can see a lot of usefulness for it, since it gives you a "written record", so to speak, of information instead of relying on voice. I've done work tracking runners in 50k trail runs with no cell service, and it would be very useful to "text" runner numbers back to race control rather than dictate them over the air and have someone try to hear and write them. 

[Blaise]

Ooohh, I never thought of that, the error correction would eliminate most of the issues you get with a weak or spotty signal...

[Borage257]

If you use an APRS cable ( Btech or other) you get much better signal transfer. Brief text and location data transfer are allowed on simplex.

Check out andFLmsg works well too, more modes, forms etc. Works better too.

[flashover52]

I have used it on ham bands. Wondered how long it would be before FRS and GMRS radios found it. Interesting technology even for one who uses Winlink & APRS a bit.

I was under the impression that there are only small exceptions for “data” that is passed over GMRS frequencies. I thought it was limited to the GPS stuff the old Garmin Rino’s used to send location data; but I guess we could text through that.

[axorlov]

15 minutes ago, flashover52 said:

Interesting technology even for one who uses Winlink & APRS a bit.

Yes, AX25 packet over AFSK does not use any(!!!) error correction, so it is much-much less reliable than voice in the same environment. Ribbit guys thought of it, and it's impressive that data survives the audio coupling + over-the-air noise. It would be interesting to compare the bandwith of Ribbit and AFSK under real life conditions.

[Raybestos]

Great, another excuse to clutter GMRS frequencies with digital noise.  

MURS (already thoroughly cluttered) or ham might be great places for this technology, though.

[Borage257]

95.1731 Section (d)
Digital data. GMRS hand-held portable units may transmit digital data containing location information, or requesting location information from one or more other GMRS or FRS units, or containing a brief text message to another specific GMRS or FRS unit.

 

§ 95.1773 Section (c)

Digital data transmissions. Digital data transmissions are limited to the 462 MHz main channels and interstitial channels in the 462 MHz and 467 MHz bands.

 

95.1787 GMRS additional requirements.

 

Each hand-held portable unit transmitter type submitted for certification under this subpart is subject to the rules in this section. 

(a) Digital data transmissions. GMRS hand-held portable units that have the capability to transmit digital data must be designed to meet the following requirements. 

(1) Digital data transmissions may contain location information, or requesting location information from one or more other GMRS or FRS units, or containing a brief text message to another specific GMRS or FRS unit. Digital data transmissions may be initiated by a manual action of the operator or on an automatic or periodic basis, and a GMRS unit receiving an interrogation request may automatically respond with its location. 

(2) Digital data transmissions must not exceed one second in duration. 

(3) Digital data transmissions must not be sent more frequently than one digital data transmission within a thirty-second period, except that a GMRS unit may automatically respond to more than one interrogation request received within a thirty-second period. 

(4) The antenna must be a non-removable integral part of the GMRS unit. 

(5) GMRS units must not be capable of transmitting digital data on the 467 MHz main channels.

[Borage257]

Think that about covers the digital GMRS rules

[Blaise]

4 hours ago, RayP said:

Great, another excuse to clutter GMRS frequencies with digital noise. 

Compared to the DMR crap regularly blotting out GMRS channels for hours at a time, I would think that a few 1-second bursts per minute at ultrasonic frequencies would be a trivial concern!

[WRUU653]

4 hours ago, RayP said:

  MURS (already thoroughly cluttered) 

Seriously asking where is this happening? Is this in a big city? Industrial area? Other than the Walmart parking lot Murs around me is pretty darn quite.

[Raybestos]

There are areas in and around the Greater Columbia (SC) Metro Area where you hear incessant DTMF streams, digital noise, dead carriers, and other stuff on a pretty near constant basis.  As big cities go, this is not one of the larger ones, therefore I would expect the same or worse in other areas.

[Raybestos]

On 9/22/2023 at 10:06 AM, Blaise said:

Compared to the DMR crap regularly blotting out GMRS channels for hours at a time, I would think that a few 1-second bursts per minute at ultrasonic frequencies would be a trivial concern!

The unlawful DMR stuff is bad enough.  That, however, is not a good excuse to add to the pile and make it worse.

[SteveShannon]

On 9/22/2023 at 8:06 AM, Blaise said:

Compared to the DMR crap regularly blotting out GMRS channels for hours at a time, I would think that a few 1-second bursts per minute at ultrasonic frequencies would be a trivial concern!

Ultrasonic frequencies are not transmitted by voice mode radios such as GMRS.  The available bandwidth severely limits both the audio frequencies that can be carried as well as the data rate. Any Ribbit transmissions will be right in the most audible frequencies that humans hear.  Ribbit transmits using the audio frequency range of 500 Hz to 2500 Hz.

[WRQC527]

I've said this before. As much as sending text messages over GMRS sounds like a neato idea, (which it kinda is), it's yet another example of trying to make GMRS something it was never intended to be. As much as amateur radio gets maligned on this site, the list of ways GMRS wants to be like amateur radio keeps growing. Linked repeaters carrying transmissions into other states, internet setups like Zello, and texting apps like Ribbit. The problem is that GMRS has a very limited 5 mhz slice of the UHF band, and it's channelized. Cramming more and more into it is eventually going to overload it. I'm a bit of a purist, so in my humble opinion, leave it alone and use it for, as the sum of all human knowledge, Wikipedia, says, (I say that with tongue firmly planted in cheek), "short-range two-way voice communication and authorized under part 95 of the US FCC code".

[SteveShannon]

Well, officially,GMRS is:

Quote

95.1703 - A mobile two-way voice communication service, with limited data applications, for facilitating activities of individual licensees and their family members, including, but not limited to, voluntary provision of assistance to the public during emergencies and natural disasters.

 

[UncleYoda]

2 hours ago, Sshannon said:

Ultrasonic frequencies are not transmitted by voice mode radios such as GMRS.  The available bandwidth severely limits both the audio frequencies that can be carried as well as the data rate. Any Ribbit transmissions will be right in the most audible frequencies that humans hear.  Ribbit transmits using the audio frequency range of 500 Hz to 2500 Hz.

Maybe I'm not thinking clearly (not enough coffee yet perhaps), but aren't y'all mixing up 2 different things?  We don't hear radio waves.  We hear the sound waves that the receiver converts the radio waves into.  When we say we hear digital noise we are hearing the sound the radio puts out not the radio waves themselves.  So all that matters for what we hear is can the radio receive it and convert it to audio.  For example, AM broadcasts don't cause any recognizable signal on my 2m radios.  (Out of band signals like that may contribute to the background static/white noise but not in a distinguishable way.)

[SteveShannon]

46 minutes ago, UncleYoda said:

Maybe I'm not thinking clearly (not enough coffee yet perhaps), but aren't y'all mixing up 2 different things?  We don't hear radio waves.  We hear the sound waves that the receiver converts the radio waves into.  When we say we hear digital noise we are hearing the sound the radio puts out not the radio waves themselves.  So all that matters for what we hear is can the radio receive it and convert it to audio.  For example, AM broadcasts don't cause any recognizable signal on my 2m radios.  (Out of band signals like that may contribute to the background static/white noise but not in a distinguishable way.)

I guess you’d have to ask Blaise what he meant when used the term “ultrasonic”.  To me it sounds (no pun intended) like he thought that he was saying that this method of sending text messages would not be audible to people listening to the affected frequency because they would be in the ultrasonic range:

On 9/22/2023 at 8:06 AM, Blaise said:

Compared to the DMR crap regularly blotting out GMRS channels for hours at a time, I would think that a few 1-second bursts per minute at ultrasonic frequencies would be a trivial concern!

[Blaise]

19 hours ago, Sshannon said:

 To me it sounds (no pun intended) like he thought that he was saying that this method of sending text messages would not be audible to people listening to the affected frequency because they would be in the ultrasonic range

This.  I was able to send a message at 20100Hz over a Talkpod to a Baofeng.

Is that not supposed to? My methods are hardly scientific...

[Blaise]

22 hours ago, WRQC527 said:

it's yet another example of trying to make GMRS something it was never intended to be.

My kneejerk response to this is: So? Who cares?  My dishwasher wasn't "intended" to be a sterilizing kiln for my homebrew beer-bottles, but it works great at it, and gives me a lot of added utility.  The decorative tower on my rescued Victorian home wasn't "intended" to be an antenna mount, but it does a fantastic job, and gives me a lot of added utility.  The internet wasn't "intended" to be a corporate-dominated wilderness of false information and endless scammers, but... OK, that one's a bad example...

My more thoughtful response is: If something is intended to "facilitate our activities", and we find a new way to facilitate our activities with it, isn't that the very definition of "intended"?

 

[SteveShannon]

22 minutes ago, Blaise said:

This.  I was able to send a message at 20100Hz over a Talkpod to a Baofeng.

Is that not supposed to? My methods are hardly scientific...

No, that is not supposed to .  How did you measure the audio frequencies?  

Edited to add: I don’t know if you saw the other thread where Ribbit is mentioned, but if you did then you know I’m not against it.  I intend to play with it in the amateur bands.  

[UncleYoda]

Huh?  20.1 KHz on a Baofeng - what model RX's that?  (I have no idea what a Talkpod is, and probably don't care.)  In any case, frequency of a radio transmission does not equate to sound wave frequency (as I said in my comment above).  An RF signal has to be converted to sound by a radio for us to hear it; otherwise, we'd hear constant noise or static coming through the air, like a radio with open squelch.

I'm not sure that I, or you for that matter, know what you are trying to do.  Are you producing a tone on the Talkpod and having a Baofeng "hear it" with the PTT pressed down?  If nothing else, that would at least result in an open carrier even if the tone isn't audible.

[Blaise]

Just now, Sshannon said:

How did you measure the audio frequencies?  

I did not.  I set both apps to 20100 Hz, set them next to radios a couple of dozen feet apart, pushed the PTT, and clicked send, and confirmed reception.  I simply took the app's word for it.  In fairness, I could only hear a little crackling, not the usual data-burst, so I'm *pretty* sure it was ultrasonic, but otherwise, I did not have a proper experiment set up, so I can't truly confirm anything...