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So we're saying that if I take a mobile GMRS radio and hook it up to an external antenna and an external power supply at my desk inside the home, which, I think, makes it a base station, at that point I'm not allowed to use it to hit a GMRS repeater?

Probably should have started a new thread, since this is a new question largely unrelated to the original thread, that hasn't been active since 2022. But I'll try to answer: If you hear the squelch tail it means you opened squelch on the repeater, which means you are at least getting enough signal through for the repeater to hear your PL tone or DCS code. Others should be able to hear you. Squelch tail is the sound the repeater makes when it is transmitting, but not still receiving a signal, but hasn't had enough time to stop transmitting yet. Here's the sequence of events: You key up. Repeater senses a transmission on its frequency. Repeater detects that your PL tone is the one that it requires to open squelch. Because it detected your tone, the repeater opens squelch and listens to you, while at the same time retransmitting your signal (which is coming in on a 467.xxxx frequency) out to everyone listening on the 462.xxxx frequency. Other peoples' radios hear a transmission on the repeater output frequency. Other peoples' radios decode the PL tone and open their squelch. You talk for awhile. You release your key. The repeater stops receiving a signal, but is still transmitting for a brief moment. The repeater notices the signal went away and stops transmitting. Receiving radios notice the signal went away and stop receiving. The squelch tail people hear is step 9 through 11. The repeater is transmitting for a brief moment without any input, so there's a short moment of some subdued static, your radio's squelch stays open during this time because the PL tone and carrier signal strength are holding the radio open. If you hear this, it means you hit the repeater. Now, why you can't hear yourself... why were you expecting to hear yourself (this is an actual question). Is it because (1) You think you should be able to hear yourself like you do on a telephone, or (2) because you had another radio nearby that was receiving? If it's "1", that just doesn't happen. GMRS radios operate on half-duplex while working repeaters. Telephones use full duplex. If it's "2", that's usually because the second radio is so close to the transmitting radio that its reception it totally overwhelmed by the power coming out of the transmitting radio, to the point that it doesn't hear the distant repeater's transmission. Think of it this way: If someone shouts at you from 100 feet away in a quiet setting you will hear them. If someone shouts at you from 100 feet away while you have your car stereo blasting at full volume, you won't hear them. The person 100 feet away isn't putting out any less volume, it's just getting lost in all the noise. The usual solution is to have someone take that other radio a tenth of a mile away and listen there, so that your transmitting radio's RF energy isn't overwhelming the listening radio's receiver.

I stand corrected. Apologies on that front.

A: The FRS channels predated GMRS channel numbering. When the services combined on frequencies, the frequencies were layered in. Additionally, the 15-22 frequencies, and the repeater input frequencies are the "mains", while the 1-7 and 8-14 are the interstitials; they are intentionally lower power (5w or 0.5w depending on the channel) so as to have less potential for interfering with the mains. B: Every FRS and GMRS radio I've used (Motorola FRS radios, Midland GMRS handheld radios, Motorola combination radios from before the rule change, Baofeng GMRS radios, Midland mobile radios, and Retevis mobile radios) use the same channel numbering. The earlier FRS didn't have channels 15-22. But aside from that the numbering has remained unaltered. You'll have to demonstrate model numbers that shipped with incorrect channel numbers per frequency. Or did you alter them with CHIRP? C : Yes, GMRS and FRS use all the same frequencies, except that GMRS adds the repeater input frequencies, as well. What you get by purchasing a GMRS license: A call sign. The right to transmit on a GMRS radio Repeater capability 5w instead of 2w on channels 1-7 50w instead of 2w on channels 15-22 50w instead of no right to transmit at all on repeater inputs. Right to use external antennas (FRS is built-in antenna only) Right to use mobile GMRS radios (FRS is handheld only) on channels 1-7 and 15-22, and repeaters. Right to use base station GMRS radios (FRS is handheld only) on channels 1-7, 15-22, and repeaters. Full access to all of these capabilities for your entire family (the license is family oriented). D : The NFM (narrowband FM) setting in Chirp sets the radio to 12.5kHz or less. The FM setting (wideband FM) in Chirp sets the radio to 20kHz or less. You will also notice from your chart that the channel spacing between 15, 1, 16, 2, 17, 3, 18, 4, 19, 5, 20, 6, 21, 7, 22 is only 12.5kHz. 15, 16, 17, and so on are all spaced 25kHz apart, but the interstitials are also spaced 25kHz apart, and sandwiched directly between the mains. This is why they're called interstitial frequencies, and why they are limited to lower power (5w for 1-7, 0.5w for 8-14); as mentioned earlier, to reduce interference with the mains.

For those who don't want to bother with downloading his powerpoint and fixing all the fonts, here's the slide he posted.

Why is this posted as a question, and wouldn't it be better to just post your situation, and how you solved it, so that people can learn something without having to DM you?

What equipment is used in testing that current draw?

That's what I was eluding to with my mention of "...honor system." Out on a fishing trip away from a populated area, talking to your grandson who is on an FRS.... you're one step ahead of the game already just by having your license.

I do remember in church with my parents, as a kid in the SF Bay Area, for a couple of weeks we would witness a ton of interference coming through the building's mic system. And the system was entirely hard-wired, no radio equipment involved. The interference was unintelligible but clearly some form of modulation of spoken voice transmissions. It would cut in and out, presumably as someone was keying up a mic and talking. I'm not sure how they got the situation resolved. In ham defense, it was probably a CB operator with a blowtorch of a linear amplifier; this was the 70s, when CB was a lot more popular. I do know it stopped after a few weeks. Someone nearby was putting out some serious power with unrefined spurious emissions to be getting picked up by a PA system that was completely hardwired.

It is perfectly fine for FRS radios and GMRS radios to interact with each other. They share all the same frequencies, except that GMRS has repeater frequencies too. If you're using a GMRS radio, you should state your callsign. He, using FRS, doesn't need to. ...honor system.

GMRS has become more popular than MURS because it's better laid out (a contiguous block in the 462s, and a contiguous block in the 467s), more channels, compatible with unlicensed FRS users, repeater availability (making it more attractive to hobbiests and people who need distance), and the fact that you can get a 10 year family-oriented license for $35 without jumping through ham hoops (a test, usually an in-person testing facility). FRS is a gateway drug to GMRS. MURS is the VHF band cousin to FRS. But MURS doesn't have contiguous blocks of frequencies, repeaters, compatibility with a gazillion FRS radios already in peoples homes, MURS doesn't have contiguous frequencies; there are licensed services sandwiched between the MURS frequencies. Repeaters will probably never happen for MURS -- offsets would be really strange, and power is unlikely to go higher than 2w, to protect the paid licensees. GMRS has become popular because of the fact that it is highly compatible, easy to get into, not terribly expensive to grow with, and it's useful. ...and because it has the Queen as a spokesperson; someone who is pretty entertaining, and a prolific Youtube content creator.

It's possible I have a defective 701. If I touch it exactly where the whip meets the base, the SWR drops to 1.01:1. Move my finger away, and it goes back up to 6:1

I have a Nagoya NA-701G, and a Nagoya NA-771G. I just wanted to point out some observations about the two. The setup: Antenna -> SMA Female to PL259 Male adapter -> Surecom SW102 -> PL259 Male to SMA Male adapter -> Baofeng UV5G The adapters don't use any cable, they're solid connectors. Methodology: Cradle hand behind the radio as I would when transmitting, select a channel, PTT and observe the SWR. I tested the NA-701G and NA-771G antennas with a Baofeng UV-5G connected directly to a Surecom SW-102, connected directly to the antenna. I also tested with a stock antenna. First test was a real world test: I drove around to a few locations within five miles of my home and tested sound quality (I was recording at home using SDR++ with an RTL-SDRv4 connected to a Comet CA2X4SR). In each of my tests, the sound quality recorded was best with the NA-771G, with the stock Baofeng antenna in 2nd place, and the NA-701G in last place of the three. I would expect the NA-771G to outperform the stock antenna, but I would not expect the stock antenna to outperform a GMRS dedicated antenna like the NA-701G. Next I tested the SWR with the Surecom meter and direct connections. I carefully held the radio as I would hold it when speaking; nearly vertical, hand cupped around the back of the radio, a few inches from my face. The SWR on the NA-701G ranged between 3.0:1 and 6.0:1. These are really awful numbers for an antenna that is advertised as <1.5:1 SWR.. Then I tested with the NA-771G, and it got a nearly perfect score of between 1.0:1 and 1.03:1. Excellent. Finally I tested with the stock Baofeng antenna. It got between 1.01:1 and 1.06:1 across all GMRS frequencies. My NA-701G and NA-771G both came in the same type of Nagoya antenna packaging. They appear to both be genuine, not knockoffs. Yet the 771G performed so well, for a handheld antenna (yes, it's quite long), and the 701G performed worse than a stock antenna. I'm not sure if perhaps I got a defective 701. It's rather hard to make a defective rubber-duck style antenna, I think, though. So this one is probably not going to get used now that I've tested its characteristics. On the positive side, it's about a quarter inch shorter than the stock antenna, and a lot more flexible. So the form factor is nice. The real silver lining is the NA-771G. Great antenna. I also tested the NA-771G on MURS, and it maintained an SWR of 1.4:1 or 1.5:1 across the MURS frequencies.=

There is not. There is nothing special about any GMRS frequencies other than the implications around power and what types of radios they can use. Channels 1-7: <= 5w for GMRS, <= 2w for FRS. FRS/GMRS simplex. Channels 8-14: <= 0.5w for GMRS, <= 0.5w for FRS, handheld ONLY. FRS/GMRS simplex. Channels 15-22: <= 50w for GMRS, <= 2w for FRS. FRS/GMRS simplex, plus GMRS repeater outputs. Repeater input frequencies 1-8: GMRS <= 50w, with outputs 5MHz lower. That's it, that's all there is to know about the GMRS channels. There are currently no special channels for emergencies, traveler assistance, nothing like that exists. A traveler assistance channel used to exist, but that stopped in the latter part of the 90s. This question does come up frequently and is answered frequently.

Strange thing: I turned on my UV5G with a 701G antenna on it and didn't pick up NOAA1 (I always pick it up), so I switched to the wider-band stock antenna, and still didn't pick up any of the NOAA frequencies. So I tuned my RTL-SDR to NOAA, and also didn't pick it up (using a Comet CA2x4SR). So at the moment, for the first time I've ever noticed, the local NOAA is offline possibly. You can check https://www.weather.gov/nwr/outages But there's no outage shown in my area. As for whether it should be able to be picked up with a UHF only antenna, that really depends on distance / signal quality. I have a GMRS-only antenna (tuned to 460-470) that doesn't pick up NOAA from my home. Other antennas do. It's possible that the bullbar antenna he's using just won't pick up VHF well enough for his area. (Update:) And a few minutes later NOAA came back up in my area.

Wishing the queen would decree that 9 is the official "kids playing walkie talkie" channel so that we could all get behind being irritated that nobody who hands toddlers a pair of radios to play with knows about the decree.

How is the antenna working out now then? I have that one that I use once in awhile. It's not my best antenna, but it's definitely my best shorter antenna (compared to my other short antenna, the MXTA25). To get any better you have to go longer.

Some sort of digital transmission that goes on hour after hour on GMRS 19 / 462.650. It's faint enough that my radios only pick it up if I have a good antenna hooked up, but strong enough that with a good antenna, even with squelch set rather high, the channel isn't terribly useful. audio_462650000Hz_12-48-09_27-07-2024.wav

That may be, but it's not illegal to use the same antenna. Antenna to diplexer to VHF and GMRS, separate radios.

I have that same antenna. it's alright. If you're looking for a 3dbi antenna it's a solid performer. If you take it off-road you might want to look for one with a spring instead, though. A 5dbi or 6dbi antenna would get you a little more range, though it would be a lot taller. For mounts you can buy any NMO mount that fits your application. Through the roof, lip mount, magnetic mount, mirror bracket, there are a lot of options. Middle of the roof will get you the best performance, so that would be a through-the-roof hole or magnetic. Midland sells double sided stickers in case you wanted to make a magnetic mount more permanent.

Of course all this is documented..... https://chirpmyradio.com/projects/chirp/wiki/MemoryEditorColumns

But I don't think the 771g is dual band. There are three versions of the 771. 771R retractable, designed for 144MHz and 430MHz (Amateur) 771 flexible whip, designed for 144MHz and 430MHz (Amateur) 771G flexible whip, designed for 462MHz (GMRS). It's a little hard to find higher gain handheld antennas for 144/440/465. As I mentioned in another post, if you are able to use a mobile antenna (with proper adapters), for example if you're at your vehicle, the Comet CA2X4SR is made for VHF amateur, VHF Murs, VHF Marine, UHF amateur, UHF GMRS, and other search and rescue frequencies in the vicinity. Great antenna for that purpose. I have one on the boat, along with a diplexer to feed a Marine VHF radio, and a GMRS radio. And I have one with my SDR dongles hooked up to it because it receives so well across such a broad spectrum of VHF and UHF.

I can confirm this. My Midland MXT275 isn't even all that new. It's the USB-C version, but I bought it sometime in late 2021 or early 2022, I think. I've looked at the spectrum with SDR++ using an RTL-SDR BLOG v4, and it appears wider when I watch the repeater input frequencies while transmitting on 15R-22R than when transmitting on 1-7 or 15-22. Additionally when I receive a signal on 15R-22R it is a little quieter than when receiving on 15-22, which is another phenomenon that can be explained by a switch in RX bandwidth. It was a PITA to test. Had to drive far enough away to avoid loading up the SDR's inputs. And I had to do it twice since repeater inputs are 5MHz above outputs, and the SDR's bandwidth is 2.4MHz.

I wasn't quite sure which category to post this in. I obtained a pair of RTL-SDR BLOG v4 software defined radio dongles. And I've spent some time playing with one of them today. It's actually pretty fun tinkering with them. And I've already learned a lot about how to configure SDR++ (aka sdrpp). One thing I haven't figured out yet: It is possible to set up dual virtual radios that can be tuned to different frequencies within the same sampling range (2.4-3.2mhz) but I think it's possible to set up two of the SDR radios at once so that multiple VFO selections can be made within separate sampling ranges. So that's the question: How do you get SDR++ to provide access to two software defined radios at the same time. Also, has anyone used one of these as a scanner? What software do you prefer for scanning? A reason for having dual SDR dongles is to be able to set up trunk tracking, but as I'm only a day in with these I'm still learning where to start.

I also find it hard to believe anyone would be terribly successful getting help in an SHTF situation if they're barging into an Amateur frequency with attitude and no license, having already been kicked out of a local GMRS group for showing attitude and disdain for the process. There's some crossover, and long memories between GMRS users and hams. Go into a GMRS group and treat people such that they kick you out, then find yourself in an "emergency" and key up on a ham repeater. Great plan.