I installed the first of two GME USA XRS-370C-U GMRS radios with AE4705B-U Heavy Duty Antenna and the remote PTT Bluetooth hands free module. You’ll never guess where the second one’s going. Hint: not in my other trucks.
I think there’s going to be everything to like about these radios. I will do an new thread and write up as I get to know them better. The biggest question on every Americans mind is whether 5W maximum is going to cut it for us. For reference, handheld GMRS usually operate at 2W with fairly weak tennis. Some at 5W. The Midland mobile units range from 15 to 50 W maximums. Our ham radio is typically can go up to 50 W. If they can manage with 5 W in the Outback, we’re probably going to be fine here.
This antenna is 6.6 DB gain which would get the longest range in open terrain and would not be optimal in Mountain terrain. But it is that thick Australian look. Shorter and lower gain whips are available and interchangeable without removing the base.
I’m not sure I’ll keep it on the Slee shortbus bumper. I also received a folding mount, which is really beefy. I can use that if I put both antennas on the roof. Whoops did I give away something about my second radio?
Slee is a GME dealer.
Disclaimer: LongCruiser is now a GME USA sponsored rig.
Ok so I attended the presentation last night, thanks again to @Pskhaat and to @sleeoffroad for hosting. I'm still trying to wrap my head around the benefit compared to my dual radio ham/FRS setups though. No matter what "2nd" radio I have, I'll still want a ham radio for APRS, the repeaters, and the fact that most of the folks I go out with regularly are all on ham. So I can't see the compelling reason to switch over? or maybe that's not the point here.
What I do see is a clear upgrade from the cheaper FRS/GMRS setups... the antenns are better, radios are neater, more fuctions with the digital stuff. But the digital stuff only matters if others in my group also have digital radios. Not unlike the digital Ham radios that I have... really only useful to the other guy on the run also on digital, and even then we forget to use it. I guess in my use case, I prefer to talk on 2m with other licensed 2m operators, and then when I have to I'll talk on FRS to people who don't want to get into ham radio, usually defaulting to the range of their handhelds. But it's cool to see the technology evolving here.
I guess my question is.. in my situation what am I missing that should compel me to jump into a GME setup and beefed up GMRS? Maybe @JadeRunner or @MarkEva or @60wag or @irbis or @Inukshuk or someone else from last night took something away, as I did have to bail early.
It comes down IMO to understanding there are two divergent worlds being overlapped.
One uses the radio as a tool for coordination and communication in support of the primary function, 4WD, overlanding, whatever.
The other is radio used for a hobby where the communication is an excuse to tinker with electronics and radios.
Ham radio only works for people who want to dig in and tinker. That's OK, it wasn't ever meant to be for everyone.
The problem has always seemed to me that adopting it as the standard in the club introduced unnecessary tension. The license holder has to be willing to understand the hows and whys. A ham doesn't have to strive to be an Elmer but they have to want to learn enough to program and tune their own radios. The knowledge has to pass down. We did those classes and the assumed ham lineage would then be those with Tech license would then teach new members. But that didn't happen. The Elmers just became radio tech support over and over.
That's why I suggested jumping to FRS/GMRS as a standard. It is fire-and-forget. Mostly. No one picked up the Ham and Eggs, for example.
I don't know if it ever came up but the way I thought about it was "Do you want to be a ham club that goes wheeling or a wheeling club that uses radios?"
It is (and should be) absolutely clear that Rising Sun is a Toyota 4WD club. So those of us who are hams shouldn't have imposed our hobby on that. We can do ham as a subset but we have to be accommodating to everyone and that means picking a universal platform that doesn't require exceptional effort to participate.
FRS is really ideal at that. It is limiting in quality and range, but that's the trade-off for ease of use. If you want to improve that at minimal effort GMRS does that, too. You get nearly all the benefits of 50W, wide bandwidth VHF/UHF FM without much technical overhead.
Honestly, for all the talk of repeaters my observation is that most RS hams are extremely mic shy using them. GMRS has a few and it only takes asking owners for codes.
APRS is a little more used but I would argue it's really only embraced by a few of us as more than a no cost position tracker. It's supposed to be a two-way system, messages, weather, object data.
There is no equivalent in GMRS, it's generally against the rules in the way we use it on ham. If I understand the FCC interpretation it may be legal to implement it as a position prepend, like I think Garmin does with some of their Rino radios. But connecting a TNC/modem to your radio and doing data on GMRS is not allowed.
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I've resigned myself to having two radios (or three). This no different than it ever was. I had a CB and a ham radio originally and just traded the CB for GMRS.
All the "issues" and "personal preferences" aside and my own "personal/professional experience" thrown in the trash, I was absolutely impressed with the GME tech and features for $350 mobile radio.
I've used $10,000+ HT's and "god knows how much" mobiles that couldn't/wouldn't work across a parking lot and I would have given $$$$$$$$$$ for their Replay feature or Crew talk feature when the s@@$ hit the fan.
APRS is a little more used but I would argue it's really only embraced by a few of us as more than a no cost position tracker...
There is no equivalent in GMRS, it's generally against the rules
Data is allowed on GMRS, but only on radios with affixed antennas. Data must be less than 1000ms no more than every 30 seconds. 47 CFR § 95.1787(a).
Garmin has a FCC Part95 waivers. I also have a filed waiver petition into the FCC for something very similar.
The great thing is, since GME gets firmware & software updates, when the FCC rules in favor of data, you won't need a new radio, it will simply be enabled.
First, awesome to see you and thank you so much for coming. I think really, GMRS is evolving into the "simple" go-to for radio comms; access is easy. GME sees that radio band as the excellent opportunity to innovate.
There are a lot of benefits of GME regardless of what radio is on the other side, but yes some of the cool stuff does need another radio with the same. That's par for course though, e.g. APRS. GME will always be able to talk to any other GMRS radio.
I like the look and specs of the GME radio but at 5 watts I wonder what I'd be leaving on the table over the Midland 50 watt radio. Kind of like buying 33's when I know 40's will fit.
I like the look and specs of the GME radio but at 5 watts I wonder what I'd be leaving on the table over the Midland 50 watt radio. Kind of like buying 33's when I know 40's will fit.
I attended the presentation last night as well. I appreciate @Pskhaat and @sleeoffroad for hosting.
The case GME made was for people using a 50 watt radio and also using the smaller ghost antennas. Which I don’t think necessarily is a completely fair comparison but I hesitated in bringing it up during their presentation.
I guess the question to me Tim is then why not just get a better antenna? You could buy a higher quality antenna for your current radio (using their example of 50 watts) which is far less expensive than purchasing a new GME radio and their antenna setup. But maybe there’s something I’m missing??? I’m definitely not a subject matter expert.
I personally already have a Midland 575 w/50watts with a 6.6 db antenna and unless I wanted some of the tech features of the GME radios I personally think it’s a hard sell. I’m not a guy who needs the latest product or the highest level of tech available but I don’t fault those who are. Obviously as I’m still rocking a IPhone XR. Now if I didn’t already have a radio I could definitely see the value in their system. The steering wheel button for push to talk was pretty slick.
Antenna gain works in both directions but power only helps the transmit side.
Remember your amateur licensing test...
47 CFR 97.313(a)
"An amateur station must use the minimum transmitter power necessary to carry out the desired communications."
It's conceptually true for all two-way, not just ham radio.
If you have a poor antenna but lots of power your TX signal reaches beyond your RX range. This means you could be talking over people and not know it.
You want to start with low power so you're hearing stations that can't quite hear you. Then you can increase power until you reach parity, your RX and TX ranges are the same.
This is especially important in mixed environments with HTs and low performance antennas. The mobile stations need to be doing more of the work to pull in weak TX signals from FRS radios, so antenna RX is critical.
Data is allowed on GMRS, but only on radios with affixed antennas. Data must be less than 1000ms no more than every 30 seconds. 47 CFR § 95.1787(a).
Garmin has a FCC Part95 waivers. I also have a filed waiver petition into the FCC for something very similar.
The great thing is, since GME gets firmware & software updates, when the FCC rules in favor of data, you won't need a new radio, it will simply be enabled.
I'm not a communications lawyer but my understanding is Garmin doesn't have a waiver but rather got the FCC rules changed to allow Rino radios.
47 CFR 95.1731(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."
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.
(b) [Reserved]
There are a few ways hams use APRS that remain against GMRS rules other than the portable/fixed antenna rule.
One is connection of an external device (e.g. the TNC/modem) to the radio. If GME is putting disabled modems in their hardware they might leverage it as a feature but the spirit of APRS is open source for experimentation. Seems like having a way to allow retroactive use on existing user base would be necessary for it to catch on.
The hardware cannot change once the radio is type accepted and even firmware might not fall under end-user permissible if it changes modulation, so the radio would have had to be originally accepted for F1D/F2D along with F3E. The potential exists to create a lot of interference with digital modes with poorly tuned modems and radios, so the FCC is trying to front run a huge headache.
Another, more critical IMO, is the linking of all the digipeaters over APRS-IS and the gateways to the Internet. GMRS repeaters cannot be linked other than for control. This is unlikely to change, especially in light of the clear statement the FCC made.
But even if the rule was somehow changed to allow communication along with control over the telephone (or RF link, which is also not allowed) network was changed the dedication of 144.390 to APRS (in North America) would pose a problem for GMRS. How many GMRS repeater owners are going to want to leave their repeaters open and dedicated 24/7 to data?
Not to mention that there's only just the 8 channels and they're dual use with simplex. That's a lot of spectrum to dedicate. Would have to consider if the FCC would allow store-and-forward on one frequency, presumably to utilize the normally lightly used repeater inputs for this. I don't know the coordincation infrastructure of GMRS to gauge the feasibility of this.
GMRS is not supposed to be light duty ham radio. It's supposed to be a defined local use system. Why spend the money and indeed why would the FCC allow GMRS to duplicate the already extensively built out ham packet networks and the commercial satellite posit locators?
@DaveInDenver
Thank you for the TX/RX reminder. It’s been a few years. That is a great point but still doesn’t really address my question. Those of you with 5watt GMRS, do you wish you had more? My experience with HAM is that I rarely ever bump my power over 5watts. I have on occasion but it’s rare. Are you GMRS users finding you power up more often than HAM?
Regardless of my radio power I will want a good antenna.
My rule-of-thumb is generally Channels 1-7 for convoy communication. Those channels are capped by any legal GMRS radio at 5 watts anyway. I can reach to most all reasonable visual horizons with 5watts (even if I had a 50 watt radio).
Story about 50 watts:
Last year, I had to leave (had to be back to work) a great convoy heading down into HITR West; it is a bunch of mini canyons as you get further South. I was scanning all channels as I left them, wishing them the very best. I had forgotten something and they tried to "radio me" as I left, with 50 watts on our designated "high" channel. I never heard them at all, I was never more than a few miles away; they were in washes with rock walls.
As I made it back (about 4-5 hours of driving north) to the pavement, I heard them again. They were on our convoy channel 5 (5 watts), just having fun. I bid them farewell again and I had made it back to pavement. I was asked if I heard them now why I didn't respond earlier. Truth is UHF as we all know is line of sight. Power mattered in that scenario little if any. 5 watts while we were all on higher ground was much more than perfectly fine, and perfectly crystal clear too.
Now this can be reason enough for people wanting HF or VHF and that's totally cool, but the power argument in GMRS (UHF) is nuanced.
Now, having had VHF (2m ham + MURS/RR), UHF (GMRS), and CB radome antennas manufactured for years (my old Alamosa Antenna company), I can tell you sincerely the GME (granted only GMRS) are tops and I'd personally consider nothing less.
@DaveInDenver
Thank you for the TX/RX reminder. It’s been a few years. That is a great point but still doesn’t really address my question. Those of you with 5watt GMRS, do you wish you had more? My experience with HAM is that I rarely ever bump my power over 5watts. I have on occasion but it’s rare. Are you GMRS users finding you power up more often than HAM?
Who do you intend to talk to? What are they using? Those are the bottom line radio questions.
On GMRS you can only use 5W on 1 to 7. Then 8 to 14 interstitial channels are limited to 1/2W with fixed antennas. You can't TX on them with a external antenna mobile. The only place you can even really stretch your legs are 15 to 22. So having 50W means everyone in the net has to have 50W.
I have a 25W radio as my GMRS and I can't remember last time I used more than 5W on GMRS. I have 3dBd of antenna gain (Larsen 2/70B).
The antenna helps, 3dB of gain is the same as 2x power (this is the general formula, doubling is 3dB, quadruple is 6dB).
Going from 1/2W to 5W is 10dB. It's also 10dB going from 5W to 50W. To give a few more references. Going from 5W to 15W is just slightly less than 5dB. Going from 15W to 50W is just a bit more than 5dB.
That jump from bubble pack FRS radios with terrible antennas to even the most basic 5W mobile radio with external antenna is a huge step.
The rule of thumb in terms of path loss is that it takes about 6dB of power (e.g. 4x increase) and/or antenna gain to double your range.
If you planned to use repeaters having 50W might be nice but most of us are going to move over to ham if repeaters are involved. Even then it's rare I use 50W, mostly in the 10 to 30 watts range depending on what is the "mid" setting of the particular radio. I by far have all my mobile radios set to "low", which is pretty universally 5W.
Just my $0.02 but the sweet spot is 15W and a good antenna in terms of where best to stop spending money on GMRS. If budget is constrained work on the best antenna and mount you can with a radio of 5W.
Think about it this way, we are limited on most bands to 1500 watts PEP but what's the maximum you've ever used? Probably 50W. There's the legal or theoretical maximum and there's what you actually need and use.
I enjoyed the presentation and trying to come up to speed on these new GME digital GMRS radios. What a great improvement with nice new features. I will certainly be getting one someday. Probably for general comms in my Tacoma for road trips next.
As an occasional user on trail runs in my 4Runner. For now, anyway, my Midland 400 with ghost antenna seems to work just fine. And like @nakman said I prefer the HAM with fellow club members whenever possible. But on the last few runs - we were just on GRMS. Have to stick with the lowest common dominator more and more. Using two radios in the JadeRunner on difficult trails (or snow runs) with twin sticks blows. Don't want to do that again if possible. Picture tangled mic cords and responding on the wrong radio. Ha.
I look forward to the day we these new digital radios are the "standard". I hope that will happen quickly. Then the Midland 400 and little ghost antenna will have to go.
Shorter and lower gain whips are available and interchangeable without removing the base.
RR), UHF (GMRS), and CB radome antennas manufactured for years (my old 
