GMRS rule change re data transmission coming

[Michael Gold]

Sometime this month I expect the Federal Register will publish an announced new GMRS rule that would become effective 30 days later. Under existing rules a data packet had to be manually transmitted. Soon FCC will allow GMRS data to be automated or periodic. You could remotely request the data, or the data could simply emit as often as 1 second out of every 30 seconds. There is some risk that could become annoying. However, there are various strings attached concerning type of radio and emission type; and the message must address a particular GMRS or FRS station. Also, the rules will continue to forbid data over repeaters.

Though there's risks of annoyance from periodic transmissions, and there's still no prospects of data over GMRS repeaters, looking on the bright side I think GMRS simplex data might have value for the BeCERTAINN community. The FCC's justification was based on a scenario where someone needs assistance and might not be able to respond manually. A yet-to-be-marketed GPS-equipped radio will be able to ping periodically, or to automatically respond to queries by search and rescue teams. But the rule isn't limited to GPS, it also includes "text...to another specific GMRS or FRS unit". Sounds to me like, subject to that 30 second timeout, with help from various hacks the new rule would allow a GMRS weather station to respond to a query; or any station could simply respond in a way that lets you query signal strength without help from another person. I realize that 1 second of data is very short, but I am not quite ready to rule out the possibility of sending an ICS form, through use of various technical workarounds and loopholes in the rules. In any case I can imagine a scenario where your phone's sound chip is on the job helping your GMRS radio transmit and receive a limited amount of data, even though no cell towers are available for the phone to reach by itself.

As long as I'm on the subject of rules and the FCC, we are still waiting for official word of when the GMRS license fee will fall from $70 to $35. I imagine when the fee reduction finally gets published in the Congressional Record, the news will spread quickly.

Best regards,

-MG

WRJB283 & AJ6RZ

[Doug Mosher]

Thanks Michael for that update. Hopefully with the 1 second of data there won't be a rush to introduce devices like weather stations that use GMRS--those 22 channels are all we have.

Has anyone ever used the Garmin Rino 750/755 GPS/GMRS radio combo? They use position reporting via the FCC's 2017 rule to allow short data/text/GPS data over GMRS. Manually transmitted as you note.

1 second of data transfer will be very limiting. One can (I do) use an Amateur/Ham radio with a TNC (basically a modem) to transmit data, for example during Red Cross exercises. Data includes files, email (Winlink), ICS forms, etc. Very slow though (1200 baud, lots of handshaking) --an ICS text/XML form can take several minutes and a 70KB image for example can take over 15 minutes to transfer. 1 second transfer every 30 seconds will take a long time for a ~15KB filled-out ICS-213 form (someone can do the math).

But still, as you note, potentially useful. Thanks again,

-Doug
WQOY819 / KI6DOG

www.genoak.org

---------------------------------------------
 Doug Mosher
 OCP&R Program Manager
 Oakland Firesafe Council
 415.297.7457
 www.oaklandcpandr.org

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[Michael Gold]

Hi, Doug. First, I often enough tell people about your digital ICS form supporting transfer of net control, trying to generate some enthusiasm for the general topic - Oakland is ahead of the curve.

On the flip side, I haven't yet found an elmer/partner who will ditch the TNC. I'm more thinking of a cable adapter between a GMRS radio's K1 (mic) connector and the headphone jack of a computer or smartphone. See also YouTube for folks Android or Macintosh to run fldigi. I think fldigi could very likely issue a Part 95-compliant signal quality report or weather report in 1 second.

Now, as to why I would not rule out an ICS form in 1 second. First, Part 95 allows "text"--an image does not comply with Part 95 and to stay on the safe side I would not use pdf. ASCII has new line (carriage return) and tab keys. Call it 8 bits per character. 1000 characters would be 8 kbits, well within the 56 kbaud limit that Part 97.305 states for 70 cm band. I think that limit is one indication that thousands of characters per second are technically feasible, depending on signal quality. Again, might be fldigi or something else.

Yes there is definitely a risk of the result being more annoying than useful. I'm tending to think GMRS will not see much data except using whatever radio Motorola has planned - they were the ones who've been waiting for the rule change - plus whatever the DIY community comes up with. What I have in mind would probably need a disclaimer for the general public: `Warning - may crash or brick your smartphone'.

Re Garmin Rino, no, I don't know anyone who uses it. It doesn't seem like a very practical  solution, partly because it only works with other Rinos as far as I know. I expect similar compatibility issues with Motorola.

Best regards,

-MG

[Shakti Das]

First I plead ignorance to what type of protocols or data encryption will be allowed on GMRS. Is it AX.25, X.25, VARA, PACTOR, or what? I have done packet (ax.25), Vara HF, Vara FM, PSK, and fldigi. It's unrealistic to get any message via radio through in one second, especially using fl-digi.

Let me ask you if you have inquired into vara fm (which seems to be the fastest speeds that can be sent over ham radios)? It''s used extensively world wide and very frequent here in the Bay Area.

What is your main purpose for digital comms? Is it weather, location services, EmComm, chatting, mailbox servers?

Regarding the license fee change over it has already been published in the federal register; however the FCC has stated publicly that it will take as long as early 2022 for the to correct all their data bases for the changeover that increases the ham fees $35 and decreases the GMRS fees $35.

BE well and prosper

Don, wqxj891

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[Michael Gold]

> what type of protocols

As a practical matter I (and I suspect FCC) was thinking solely of data bursts, which do not necessarily fulfill the usual meaning of packet. Forward error correction OK.

As you may know, a packet protocol typically has automated repeat requests and forwarding. In theory, OK, but only if within the 1/30 duty cycle limit. I would not attempt packet over GMRS, the overhead would get in the way of the message payload.

> VARA

Thanks for drawing my attention to it. I see that in Wide mode it encodes/decodes at 9600 baud. Certainly 9600 bits/s, if I could achieve it, is enough to get a 1000 character message across in 1 second. If someone can cite physics or US code to prove it can't be done, I'm all ears. Otherwise I'll be saying over and over "I myself would not rule that out".

> What is your main purpose in using digital comms?

Emcomm is what's motivating me. The new FCC ruling emphasizes GPS over GMRS for search and rescue, certainly some relevance to emcomm. I do think automated weather and signal strength reports would be helpful for GMRS users who are ready to respond in an emergency. In my opinion there would also be an advantage if a GMRS licensee could quickly transfer a net roster to another GMRS licensee. Because of the duty cycle limit, the ruling does not seem too helpful for chat or mail, whether or not these are seen as helpful for emcomm.

Regards,

-MG

WRJB283 & AJ6RZ

[Don WQXJ891/NI6A]

MG, Perhaps, but yes, take into consideration the urban GMRS situation. It's the wild wild west out there :)

Just to clarify, we know that FL-Digi is an ap, not a mode or protocol. It does not support packet (ax.25). It supports many other digital modes such as PSK, QPSK, MT63, RTTY, THOR, OLIVIA, etc. Within these modes there are sub-modes with their own protocols. For example MT63 mode uses MT-2000S, MT63-2000L, MT63-1000, and more. MT63-2000L is popular with many EmComm groups, but is rapidly being replaced by VARA FM wide. MT-63-2000L (via fldigi and flmsg)  is slow as molasses.
 
Packet on the other hand is the amateur radio protocol based on X.25 named AX.25. Other protocols exist like ft-8, ft-4, JS-8, amtor, pactor, etc. These different modem schemes cannot talk to each other directly, but messages can be exchanged via gateways such as Winlink, BPQ, etc. Winlink and VARA are the two most popular configurations for EmComm world-wide.

These are all approved digital modes by the FCC on the ham bands, as you know. The question is what digital modes will the FCC permit for GMRS?

As we both know BAUD rates are not necessarily proportional to signal width, but rather it is a symbol rate. The reason this is important is because in the past the greater the Baud rate, the wider the signal, in general. As we care about keeping the width of the signal within allotted boundaries (band widths), we find that we can stuff more bits per second (bps) within narrower bandwidths depending on the modem scheme

VARA FM wide is not limited to 9600 Baud. The “9600 Baud” requirement pertains to the FM radio that is being used. That is the radio’s audio must be capable of 9600 Baud, which means that the audio circuitry is wired to override the normal FM radio’s audio emphasis/deemphasis circuits There are many stock amateur radios that can do 9600 Baud, without hairy modifications (about 20 are generally available). To my knowledge there are zero GMRS radios on the market that can do it.

No TNC is needed or used, but a sound card might be needed if your radio does not have a built-in sound card (some do and some don’t). Many of the newer expensive radios have built-in sound cards. External sound cards run anywhere from $40-$100 if your radio does not have an internal sound card. See: http://www.masterscommunications.com/products/radio-
adapter/dra/vara-primer.html

https://groups.io/g/VARA-MODEM/topic/vara_fm_wide_mode_at_25_210/81813895?p=,,,20,0,0,0::recentpostdate%2Fsticky,,,20,2,20,81813895

There are a lot of high level software and hardware developments occurring currently mostly with Winlink and Vara.

The problem of tapping the audio I/O direct from your computer or smart phone is that it will not compensate for deemphasis/emphasis needed at the higher speeds. It will work at lower speeds maybe.

At this time 25,210 bps is the upper threshold for Vara FM Wide on the VHF/UHF bands with radios capable of 9600 baud and a sound card (built-in or external).
https://www.youtube.com/watch?v=G2topwHfbpw

My experience is that using any modem scheme that I am aware of, even a short message of 10 words, will take 10 seconds or more. The average IC-213 form that is filled-in and typed and formatted (10 seconds plus or minus error free.  Theory and experimentation is always to be encouraged, but I also encourage you to get on vara or any of the other digital modes. If you get your hands-on experience now on VHF/UHF you most likely will be able to apply that experience for GMRS. I am not discouraging that..

Others can suggest what radios and soundcards might work for your application. I’m just a beginner and know very little. I think that the 22 channels limited to GMRS may not be adequate for urban digital GMRS comms. Perhaps manufacturers will come up with a standard for all modes? It's kinda vapor-ware at this point, but an interesting speculation.

The Sky is the Limit (FCC willing).

Don WQXJ891

[Brian Shiratsuki]

On Thu, Aug 19, 2021 at 1:50 PM Michael Gold <contac...@gmail.com> wrote:

> ...Yes there is definitely a risk of the result being more annoying than useful. I'm tending to think GMRS will not see much data except using whatever radio Motorola has planned - they were the ones who've been waiting for the rule change - plus whatever the DIY community comes up with. What I have in mind would probably need a disclaimer for the general public: `Warning - may crash or brick your smartphone'.

most of the public safety radio around here goes over p25, which uses
a modulation called c4fm. it can do 9600 bps in the 12.5 kHz of an FRS
channel. DMR uses 4FSK, which doesn't seem to do as well. either way,
it would seem all the participating radios would need some sort of
address configured by the user or burnt in during manufacture.

> Re Garmin Rino, no, I don't know anyone who uses it. It doesn't seem like a very practical solution, partly because it only works with other Rinos as far as I know. I expect similar compatibility issues with Motorola.

both p25 and DMR are meant to facilitate interoperability. however my
DMR set has two messages in its outbox addressed to martha, who
probably didn't actually receive them despite both of us having radios
using an official chinese standard.

brian
n6sxt

[Michael Gold]

The video with 25 kbit/s is interesting. Anyway, in good conditions 25 kbits less 20% for overhead would yield 2500 8-bit text characters in 1 second.

> The problem of tapping the audio I/O direct from your computer or smart phone is that it will not compensate for deemphasis/emphasis needed at the higher speeds.

I expect there are manufacturer-authorized tweaks to get that kind of flat audio response using some commercial radios, imaginably including Kenwood TK-880.

Note FCC green-lighted "surplus" commercial radios for use with GMRS. (FCC: "not our intent" to "prevent GMRS licensees from using surplus Part 90 equipment in GMRS", footnote 149 page 24 here). 

> The question is what digital modes will the FCC permit for GMRS?

It's too early for me to be saying to anyone else "here's a legal and practical recipe for transmitting data on GMRS".

But say I did have 2 or more commercial FM radios set up in accord with their service manuals -- then I might imaginably fulfill the FCC's "not our intent" statement above using any public algorithm that encodes digital text into lowpass 3.125 kHz audio; or by using any built-in mode fed by a factory-equipped data port if present on the commercial radio. Further I would transmit at 5 watts or less (not 50), within the duty cycle limit of 1 second per 30 seconds, and within the new rules regarding manual, automated, and periodic transmissions.

Now the only reason "surplus" Part 90 radios are just barely legal for GMRS is because FCC responded to requests from radio operators, notably KE4FHH, who asked FCC very nicely. Maybe someone will likewise ask for a clearly stated data loophole or developmental GMRS license.

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[Shakti Das]

Michael,

Agreed about the use of some commercial (Part 90 radios) that are type accepted for GMRS, but can those radios can't easily be wide-banded (modified) for VARA Wide FM (if VARA FM were to be approved?)

I am confused as to what you are trying to accomplish with digital modes on GMRS. If it's weather, NOAA radio is already widely available. Is it high speed IC-213 forms (which require a laptop, chrome book, or perhaps a smartphone interface if possible?

Is it GPS? Digital voice (DMR/DStar Link) or all of the above?

It seems to me that the advantage of GMRS lies in its easy learning curve and FM voice portability which lends itself to FM voice traffic. Digital data modes may be too complex for most. 

Nothing beats getting your feet wet. Jump in there and play with these modes!

Brian, DMR is a digital voice mode, not data AFAIK. I guess P25/c4fm voice has data possibilities, but I haven't heard that it is or will be allowed on GMRS channels. Do you have citations on what the FCC is planning?

I agree that, realistically, in the Greater SF Bay area we might not gain anything by automatic data transmitters. I don't really have 22 channels as there are already 3 repeaters on ch22, Lamorinda on Grizzly Peak on ch 21, GENOAK on ch. 17, and numerous more repeaters on 20-15, all of which are easy access from my location it seems that those channels already may not be available during a disaster.  Given that during a disaster all the rest of the channels will be loaded (SF, Marin, Oakland, Kensington/El Cerrito, Richmond, Berkeley, Alameda, and San Mateo County) any additional  automatic radios would add to the congestion.

Having said that, I like DMR direct (no internet or repeater). Digital Voice (Dstar) direct is also superior to FM voice. Are these modes being considered by the FCC for GMRS usage? Can you provide some citations/links?  Thanks

Best

Don, wqxj891

[Brian Shiratsuki]

On Fri, Aug 20, 2021 at 6:21 PM Shakti Das <saha...@gmail.com> wrote:

> ...DMR is a digital voice mode, not data AFAIK.

DMR has a text mode, and becomes a voice mode with the AMBE voice
codec. the proposal is for ``automatic or periodic location and data
transmissions'' on GMRS. a single second of data out of 30 is hardly
ever suitable for voice anyway. apparently FRS already permitted
``limited data applications.'' do any extant FRS sets exploit the
permission?

the other nuance is narrow-narrow FM (an addition to AM and SSB) on
11M (less impulse interference for truckers).

> I guess P25/c4fm voice has data possibilities, but I haven't heard that it is or will be allowed on GMRS channels. Do you have citations on what the FCC is planning?

no, i was just offering an estimate for how much data could be sent in
a second, using fielded modulation standards in 12.5 kHz.

what if there were a number of data-enabled, computer connected GSM
sets around the city, constantly monitoring. then if the big one hits
and i'm immobilized by a fallen beam, and have my trusty data-enabled
GSM set with a good battery in reach, it could send my location and
problem to a series of configured receivers, listen for an
acknowledgement some machine had logged it, and let me know help is on
the way. such use would exploit the automatic privilege, and enable
any configured receiver to terminate any interference with an
acknowledgement.

brian
n6sxt

[Geoff Lomax]

I am with Don, get everyone skilled with FM voice.

Digital data is secondary and can be accommodated of a variety of other platforms.

Keep it a simple as possible 

On Aug 20, 2021, at 18:21, Shakti Das <saha...@gmail.com> wrote:



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[Don WQXJ891/NI6A]

Geoff, exactly. KISS is an excellent approach IMO.

Brian, thanks for the info on DMR digital data mode. I think that DMR has many great applications in the future. The only DMR/Voice radio that is affordable and GMRS capable is the Radioddity  GD-77 that I know of. There probably are others as I have not done extensive research with DMR, yet.  However I am sure that it is neither Part 95 or Part 97 FCC type accepted.

If anyone has the link to the actual FCC NPRM, please post. I'd love to give it a once over.

Regarding GSM are you thinking of a DIY hybrid MESH system that is not connected to cell phones or the internet or are you proposing possible GSM on the GMRS/FRS channels that automatically broadcasts your data? Sorry for being a bit dense on this subject.

This is probably an arcane subject to 98% of BECERTAIN'S subscribers; so in the interest of other subscribers, let me suggest that those who are interested further create a subgroup or communicate using the CC function in private emails. Thanks for the discussion. I learned a lot.

BEST

Don, WQXJ891

[Karen Fenton]

Hi Don!

Actually, I am finding this thread very interesting. Please keep us informed. Others may feel the same way. BeCERTAINN has a lot of smart hams. 

Karen WRAP 287

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[Martha Richards]

I am also very interested in this thread, since I have an Anytone 878 HT that is both GMRS and DMR capable.  I know that a few other BeCERTAINN folks have the same radio.

 

I managed to send a short text message via DMR last year, but it was very slow -  like the early days of sending cell phone texts where there were three letters on each button and you had to tap through to get the letter you wanted.  The Anytone HT is Bluetooth capable, but I have only succeeded in pairing it with a Bluetooth headset.  I don’t think it will pair with a Bluetooth keyboard.  I would like to practice using the DMR features on my radio, and I would be interested in participating in more experiments if people want to try sending text messages or doing one-on-one or group DMR conversations via text or voice.

 

Geoff, I am wondering if it would make sense for you to form a separate Google Group for the BeCERTAINN folks who are interested in tech, and then people could decide whether they wanted to sign up or not.

 

                                                                                                                                                                                                Martha                                                

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[Martin]

Hams can send texts with free APRSDroid software.  You can buy a cable or make one.

73 Martin W6MRR

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[Don WQXJ891/NI6A]

I'm not sure if we are bothering the average BECERTAINN subscriber with these emails or not.  We all get too many as it is. Is this conversation premature?

Karen,

I'm happy that you are interested in digital voice and digital data. I think DMR will eventually be much more common in the future at least on the ham bands, and perhaps on GMRS should the FCC approve. I still have not seen the FCC NPRM, so I am left speculating and possibly wasting my breath as such. There are a lot of techies here who are much smarter that I, but without any hands-on experience might be making unrealistic assumptions.

I was concerned about the hundreds of Becertainn subscribers who are not techies but receive these emails. I don't want them to unsubscribe, so I am leaving this up to Geoff to decide. If some people decide to start a second email list, we will let you know. I am with Geoff at this point;  until digital voice or digital data on the 22 GMRS channels proves to be of an added value and not degrade the analog voice EMCOMM capabilities, we should focus on improving our FM analog voice capabilities until a capable adjunct or replacement appears practical.  

Martha, the Anytone 878 looks like a very nice radio, but since it is not FCC type accepted, I hesitate talking about it in a public forum might court some opposition.  I still don't see that as a valuable EmComm function yet, as Bridgecomm currently describes it, except that it is much better utilizing bandwidth.

My digital background is limited to hands-on packet, VARA-FM, VARA HF, FLDIGI, FLMSG, MT63-2000L, Pactor, Amtor, PSK-63, ad a little D-link on the ham bands. It's limited, but I can report on VARA, Winlink/RMS Gateways, Sound Modem, and BPQ. Relatively, my experience is limited. At this time I do not see how any of these modes or FT-8/JS-8 would work effectively on GMRS except perhaps BPQ mailbox/gateway.. But for BPQ to work on GMRS, one would need to access it via VARA or Packet. Admittedly it is a rather complicated system for the average user..

.

It's difficult to comment on the FCC changes without a copy of their NPRM. Any links?

Thanks for the dialog..

Best Regards,

Don, WQXJ891

[David Jacobowitz]

I'm not very excited about DMR on GMRS at all. I think it's a pretty bad standard for use by hams, and it will be even worse on a service like GMRS where users are generally non-technical.

The problem with DMR is that it is a commercial standard, designed to be configured by technicians and then used in radios with people with little or no knowledge of it. As a result, it's, in my opinion, not very hammy, because you basically cannot set it up from a radio, and it's certainly not GMRSy, because GMRS users are not going to make code plugs. (Experiment: take a DMR HT on vacation in some new place and see how much fun it is. Unless you bring a laptop, make a *correct* plug in advance, or just use a hotspot, you're going to be using your radio in analog FM mode!)

Now, if someone were to create some layer over DMR where radios can scan and self-discover repeaters, their slots and other configs, and what networks and TGs they are on, and display that all in the radio, then that would be much more interesting, but so far, nothing like that has happened in the ham world, much to my disappointment. I'm actually a little surprised that one of the Chinese manufacturers hasn't done this. It's a big investment, but I think if it worked, they'd probably end C4FM and DSTAR overnight.

Also, and this is much more of a subjective thing, but I find the AMBE+2 voice codec to just sound awful, sometimes unintelligible, but always unpleasant. As a casual GMRS user, I don't think I'd willingly transition from analog FM. Perhaps in some future when GMRS bw is really precious we'll have to go there, but that time seems far off to me.

Best,

Dave J

WQYU548 / WE6EE

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[Don WQXJ891/NI6A]

David, I agree about the current utilitarian lack of DMR on GMRS at this juncture. Perhaps we could revisit digital audio and data on GMRS in a few years? However DMR and DLINK are not limited to repeater use, albeit some can do both DMR and FM Voice simultaneously. I have used Dlink and friends have used DMR peer to peer simplex without repeaters, laptops, or code plugs. We have found that on the VHF/UHF ham bands DMR and DLINK have some advantages (especially regarding bandwidth). It also does not interfere with FM analog when used within 3 kHz of the FM signal! Granted the audio quality isn't its strong point, but f you can fit in, 4 DMR/DLInk signals in the same bandwidth of a single FM analog signal without interference, that may be a strong point to consider for ham simplex peer to peer digital voice Emcomm use. 

For high speed accurate digital data and data store-and-forward systems, nothing comes close to VARA Wide running RMS express.on amateur UHF/VHF frequencies.

73,

Don

[Geoff Lomax]

David, your post makes sense to me.

Pardon if I missed it, but has anyone suggested a use case for digital that would support the neighborhood level activities most of us are developing? In particular, a value added scenario above and beyond existing capacity.

Geoff

On Aug 21, 2021, at 21:59, David Jacobowitz <david.ja...@gmail.com> wrote:



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[Michael Gold]

Geoff, I hope this hasn't been too disruptive. I did bring it up, but there's certainly no urgent to-do item here. IMO foreseeable local emcomm use cases for data-over-GMRS would be GPS-assisted search and rescue, local weather/fire/propagation conditions, and ICS forms. I would strongly tend to rule out chat/texting and email over GMRS, at least until a day when advanced chips lets these data types coexist with voice better.

GPS - Local search and rescue teams might well have interest in the scenario of a lost person holding a phone up to their Baofeng or Wouxun, and squirting out GPS coordinates acoustically or maybe via  the mic connector. But after all, even if there were a popular standard data frame that S&R teams could parse I am not convinced it would be legal for GMRS considering need for coexistence of voice and data, combined with the thicket of rules. (Don, those are the governing documents for GMRS. To just read the parts that are the letter of the law today it's easier to read this page and then weep.)

Sensors - For outdoor fixed GMRS fire and other sensors, I think waivers would surely be available but only to those willing to put in the time to build something with bulletproof coexistence of voice and data on the same channel. Not a strong value proposition.

ICS forms - I believe GMRS licensees could pass ICS forms in a compliant fashion if equipped with legacy ("surplus" per FCC) wideband Part 90 radios. It's very interesting to me personally because it would delete the ham requirement for members of the community who wish to participate in digital-assisted transfers of GMRS net control stations. If anyone else has that motivation and confidence in their technical abilities, they can contact me. Now, the "surplus" loophole has given the US GMRS community repeater benefits and other benefits since 2017. In contrast, probably very few people will get a data benefit from the loophole. But some might  and it would only require a small number of GMRS-only, NCS-ready licensees in a community to do some good for emcomm. 

I guess the main take-away I've had from this discussion is--rather than focusing on data-over-GMRS, a current next step might be for me to try using the type of best of breed data-over-ham software Don has identified, to process ICS forms as Doug has done and posted about here. I do want to become involved in something like that.

Best regards,

-MG

WRJB283 & AJ6RZ

.........

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[Brian Shiratsuki]

On Sun, Aug 22, 2021 at 12:58 PM Michael Gold <contac...@gmail.com> wrote:

> Geoff, I hope this hasn't been too disruptive. I did bring it up, but there's certainly no urgent to-do item here. IMO foreseeable local emcomm use cases for data-over-GMRS would be GPS-assisted search and rescue,

since the 2017 report and order on this was due to petition by garmin,
this is the most likely immediate exploitation. the petition to amend
for automatic transmission was by motorola, so they may have other
applications in mind.

> ...ICS forms - I believe GMRS licensees could pass ICS forms in a compliant fashion if equipped with legacy ("surplus" per FCC) wideband Part 90 radios.>

the 2017 order requires permanently attached antennas for GMRS data,
ala FRS. so the regulation would require any such surplus radios
include that ``feature.''

> It's very interesting to me personally because it would delete the ham requirement for members of the community who wish to participate in digital-assisted transfers of GMRS net control stations. If anyone else has that motivation and confidence in their technical abilities, they can contact me...

i'm pretty sure the UC berkeley radio class writes modems in python.
the talent is out there, but there remain the preemphasis and other
signal purity requirements for GMRS / FRS data (see § 95.1775 GMRS
modulation requirements - § 95.1779 GMRS unwanted emissions limits,
from <https://docs.fcc.gov/public/attachments/DOC-344617A1.pdf>, p 31
or p 72).

brian
n6sxt