dosw

Let's just simplify with code A, B, C. To open the repeater you need to use its code. We'll call that input code "A". To listen to that repeater, you can either listen wide open (no code) or you can set your receiver to match the repeater's output code. "B". It's possible for a repeater operator to set A and B to be the same, which is also fine, though often they're different. It doesn't really matter; makes no practical difference once the sending and receiving radios are configured with the proper codes. There is nowhere to insert a third output code, "C", so that a subset of listeners can grab only messages coming through with the "C" tone. It's just not a feature supported by GMRS. It is possible for a high-end repeater configuration to allow multiple input/output tone combinations, though. But that's not as common, and really is up to the person setting up the repeater to configure.

I agree. I mean I don't understand the numbers behind it. But it's a pretty powerful unintentional signal. However, there was no mistaking that sound, whether it's as I lay in the MRI machine, or as I'm driving off with my GMRS radio picking it up. I don't hear it driving past other hospitals, so there must be something different about the Park City IHC hospital / imaging lab.

I'd get three mobile radios, even a MXT-275 (15W output) would do the trick, though there are more capable models that are more loved here. And get three of Midland's 6db antennas, along with three magnetic mounts, and three 12v power supplies. In each of the three homes, place an antenna in the attic or near a window on a cookie sheet for a ground plane. Bonus points if the window you place yours in is on the side of the house closest to your brother and father's homes, and on an upper floor. If your brother and father are able to go with an attic or roof-top antenna that's great, too. The Midland MXT-A26 antenna is the one to get, along with the necessary cable and a means of mounting it. With those "good enough" radios, and those "pretty good, actually" antennas, you'll hit three miles without too much trouble. The mountain could be a problem, but you're already getting past it with handhelds. All the better with a decent antenna. Come to think of it, you might just order the antennas, mounts, and adapters that fit your handhelds, assuming you're using handhelds that have detachable antennas. My UV-5G can hit a repeater 22 miles away with just its built in antenna, but when I hook it up to the MXT-A26 it sounds great.

Is there an MRI facility anywhere nearby? In March, I went for an MRI. On my way to the facility my GMRS radio was on in the car, because I'm a boring person, like that. When I got within three miles of the facility I started hearing buzzes, blips, and other strangeness on channel 17. I didn't think too much of it, until I was actually IN the MRI machine. Then I realized I was hearing the exact same sounds, the same buzzes, blips, and tones. It wasn't just similar, it was as if the GMRS radio was picking up the MRI machine's noises exactly as they sounded to me. These things are supposed to be shielded, but apparently not well enough in some cases. After my MRI as I was driving home, I heard the exact same tones, until I got about three miles away from the hospital.

Skiing Keeping the family loosely together. Finding a kid who may not have realized we've reached the end of the ski day. Not always necessary - cell service usually works. This is just one more option, and sometimes more convenient with gloves. Camping One in the car, one in the trailer, and then a few handhelds. Coordinate drop-offs and pick-ups at the nearby trailheads, call people to dinner, etc. People can engage in various activities yet still coordinate as needed. My son can guide me as I'm backing up to the trailer. Safety - With an antenna atop the trailer we get decent range; good enough to call to the trailer or vehicle for help from a handheld while out hiking, within reason. Last summer some hikers in our group got into bad weather. It was very reassuring being able to reach each other six miles apart. Group traveling I volunteer with a youth group, and sometimes we are on road trips with more than one or two vehicles. This helps us coordinate lunch and gas stops, even out of cell range. Plus it's safer than texting while driving. Kayaking or Sailing VHF is good for "ship to ship", and calling out to the harbormaster if needed. But for casual conversation and coordination, often "ship to shore", GMRS is great. "Before they had cell phones" Before my kids had cell phones we used GMRS to keep in touch as they moved about our neighborhood playing with friends or visiting the park.

I don't really like waiting through the whole 5-10 minute loop to get a few seconds of what I need, so I don't use NOAA broadcasts often anymore. Before the proliferation of connected devices like phones, it was more necessary. And NOAA reception is usually more reliable than cellular connectivity, so it does have its usefulness. I used to really appreciate having it on my Marine VHF radio in the 90s and early 2000s, for example. It is a good feature to have on a radio that you could take with you on the trail or in the back country. I'd rather not carry a separate receiver just for NOAA. I thought that the Midland handhelds offer SAME. I have a couple of older Motorolas that do, for sure. Cool feature, in principle. I've never actually gotten an alert via SAME that I wasn't aware of, though.

For those who haven't had the pleasure of laying in one of these for 40 minutes, here's the sound: https://www.youtube.com/watch?v=TIsrOtSSUQY

Yes, that's correct. The MRI sequences produce a loud buzzing sound, in pulses, at various audible frequencies. Very sharp; like if you produced a series of staccato clicks at frequencies that produce tones. A little like listening to sound effects on an old Apple ][ computer but amplified loud enough that you have to wear noise cancelling headphones. The sounds are unmistakable. As I approached, from a distance, I thought I was hearing someone transmitting a digital signal on GMRS, and was thinking "How are they getting away with a continual data transmission?" Then as I laid there in the machine, my first time ever having an MRI, hearing that sound, I realized that's what I had been hearing on GMRS/FRS 17. The facility in question is the Park City Intermountain Healthcare hospital.

I told the staff operating at the time that it caused interference from 3/4ths mile away as I approached. They seemed underwhelmed and dismissed it as "Yep, these are powerful machines." The sound follows the sequence, and is most likely not a cooling compressor, as it pulses and buzzes at various audible frequencies based on the sequence they're running. A compressor wouldn't be so precise; it would be more of a steady drone, not a sharp buzz at various pitches. I suspect it's the rapid cycling of the magnets. But I'm clearly an untrained armchair amateur. Anyway, the results are in and I'm fine.

As I approached a hospital today, GMRS 17 started buzzing loudly, in some pretty distinct sequences. This started about 3/4ths mile from the hospital. I was on my way to an MRI appointment. And when in the machine I quickly realized what I had been hearing on GMRS 17 was the MRI sequences. For anyone who has had one, the sequences are unmistakable and probably unforgettable. I just found it interesting that the interference started so far away from the hospital, and was so reliably attenuated to channel 17. I didn't hear it on 16 or 18. And the sound my radio made was just like what I was hearing inside the apparatus. And it was an intense level of interference. I don't have a question, just reflecting on the situation.

The range between 400-470 has segments dedicated to a variety of uses. One of those uses is HAM 70cm (specifically, 420-450). Other uses include a portion of the GMRS/FRS range, some could be business use, and so on. A useful HAM guide is https://www.arrl.org/band-plan That guide would also cover the 2M amateur band, which falls within the 136-174 range you mentioned (more specifically, 144-148). For a broader coverage of what might be found in the range of 400-470 and 136-174 you can look at https://transition.fcc.gov/oet/spectrum/table/fcctable.pdf For example, I believe Marine VHF are in the 156-157+ and 161-162+ range. But there are numerous services that will be found in various portions of the ranges you described. MURS is in the 151-154 range.

Could be transmitting location information. A screech sounds like there must be a data modulation upon unkey. If it's transmitting location information, that could be a Garmin.

That's really the why: I don't have a way of identifying what frequency the scanner was on when the recorder captured some output unattended. So it's just easier in my case to focus on one frequency at a time, and let it take however long I feel like leaving it running unattended.

One way that I've found repeaters is by setting a GMRS radio listening on one repeater output frequency for a few days with a VOX activated recorder plugged into it. After a day or so I'll listen to the recording. When I hear morse code, I'll take that segment of the recording and either look at it in an audio application (you can pretty easily spot the dots and dashes in the waveform graph) or upload that segment into a morse code translator. That gives me a call sign, which maps back to an individual, and in some cases can help me find the repeater's listing in mygmrs.com. After a day on one frequency, I'll move on to the next. After a week I'm almost done. With this method I've found three repeaters that I hadn't noticed before. You might try that; record each repeater output channel for awhile and listen for morse code identifying the callsign of repeater owners.

Temporary. So while your transmitting radio is transmitting on the repeater input frequency, the amount of RF energy in close proximity to the receiving radio makes it so it cannot detect the distant repeater's output even though it's on a different frequency. When you stop transmitting, the nearby receiver can hear again, but by that time the repeater is done transmitting too. You may hear a kerchunk, though. When you are vacuuming you can't hear another person 20 feet away talking at normal conversation level either, even though the vacuum may be producing noise at a different frequency than the person speaking. When you shut off the vacuum, you can hear the person speaking again, assuming your hearing was ok to begin with. The issue right now seems to be that we don't really know whether you have a bad radio, or a good radio with incorrect usage. By separating the transmitter and receiver, and having a friend listen on the receiving radio a block away (or recording the receiving radio, as I do), you can eliminate one of the possible issues. Remember, other issues could be squelch tones set wrong, or even a bad transmitter or bad receiver. But we have to strip away all the "what ifs" that we can control so that we're only left with the ones that lead to the conclusion that the radios are, or are not working at all.

Bingo. There is a reason I said you need to be spaced at a greater distance. If you transmit to a repeater, and hope to hear it on a receiving radio, you may not hear anything on the receiving radio at close proximity. WHY? The transmission in close proximity overloads the receiving radio such that it is essentially deaf. Imagine you're at a Rolling Stones concert. You shout to your friend who is also at the concert. He won't hear you. Your radio transmits on some 467 frequency. The repeater 20 miles away receives that and retransmits it on a 462 frequency. The receiving radio, five feet away from the transmitting radio is totally overwhelmed by the transmission that is occuring on 467.xxxx, and cannot hear the transmission coming from 20 miles away on 462.xxxx This phenomenon is called desensing. The output of the radio in close proximity is overloading or desensitizing the receiver in the radio that you hope to hear the distant repeater on. You need to get someone to listen on the receiving radio while you go a block away with the transmitting radio. Or do what I do; set up a VOX digital recorder plugged into the audio output of your receiving radio. Then you can walk a block away, test, and when you get back home you can listen to the results. It is entirely possible that this close proximity is not your issue. But it's such an easy thing to eliminate, and until you do, you don't really know, and we're all just chasing suggestions because diagnostic steps were skipped.

Does your home have a TV aerial that is no longer in use? It probably is grounded. And it may be in the optimal roof-mount location for your GMRS antenna.

Start simple: If in simplex, someone transmits within a half mile of you with no squelch tones set in your radio, do you hear them? If in simplex, someone transmits using a squelch tone, and you have the same programmed into your receiver, do you hear them? If in duplex at a repeater output frequency, with no squelch tone set, do you ever hear anyone hitting the repeater? If in duplex at a repeater output frequency, with no squelch tone set, plug your receiver into a digital recorder (your phone, your computer, or a handheld digital recorder), or set a digital recorder next to its speaker. Use VOX mode. Take another radio 150 feet away and transmit to that repeater using the correct squelch tone to open the repeater. Does your receiver receive it? (do you hear a recording when you get back to listen to your recorder?) Now swap the radios and do the same. Did it still work? ...again, with the transmitting radio set with appropriate squelch tones to open the repeater. Now program squelch tones for the output frequency on the receiving radio and record. Again go 150 feet away with the transmitter. Do you record anything? Notice how at each step we're trying to add only one additional thing that could go wrong. By the time we arrive at the final test, we're fully configured for typical repeater use. If you find it fails at one of those stages, you at least have eliminated the other layers as an issue. It's unlikely though possible that your radio doesn't transmit at all, or doesn't receive at all. I once had a Motorola T355R that, for whatever reason, lost its ability to transmit. So while it's unlikely, it's possible.

Start by simplifying: Transmit tone, but no squelch tone on the receiver. Transmitter and receiver should be different devices. Transmitter should be a tenth of a mile away from the receiver (just to eliminate desensing of the receiver as a possibility). One person should be listening on the receiver while you transmit hitting the repeater. If the listening person isn't hearing you, then you're either transmitting with the wrong tone (the repeater isn't using the tone you think it is, or your transmitter is set wrong), or the repeater isn't operating on that frequency, OR you're just too far to hit it, or there are too many obstructions between. If you suspect you might be using the wrong tone, get a radio scanner (borrow, buy an old one on ebay, whatever) and set it to display the PL/CTCSS tone of any signal it receives. Then set it to just the frequency of that repeater, and wait for someone else to open the repeater. Could be a long wait. Or get in touch with the owner. Many scanners will continue to display the most recently received PL tone even after the transmission has ended, so you may not have to be sitting there watching it ALL the time, but that result could be nullified by someone else coming along and transmitting on the output channel in simplex.

First GMRS was the Motorola MT355R. It was a blister pack GMRS / FRS radio that was compatible with repeaters. I didn't have a GMRS license, so would just listen on the upper channels and would transmit in low power on the first 14 channels. Second was after the MT355Rs stopped working; got some GTX1000 radios, and a license (that was earlier this year). Third was the MXT275, which I have mounted in my Bronco with the Midland 6db antenna using a hood lip mount. Fourth is a pair of Baofeng UV-5G radios. They're fun, but really the Midlands sound better. I intend to pick up either a KG905G or KG935G in the next few weeks. So, first: MT355R. Current: GTX1000, MXT275, an UV-5G; I use all three models now. I usually give the Midland GTX1000 radios to the kids because they're the simplest. Just set them to the channel and code, and lock them.

I got mine in June. $35 for ten years. Yes, the FCC website is everything I would expect of a bloated government website designed to work equally poorly for all apparent use-cases. It took 30-45 minutes to navigate through it for the first time, to figure out what the flow is supposed to be, and so on. The emailed license came a couple of days later. The price; $3.50 per year, $0.29 per month, $0.01 per day (using reduction to the ridiculous) shouldn't be prohibitive for anyone who can buy a set of radios for $50. I imagine the biggest deterrents for people are (1) Not being aware that the requirement applies to everyone, and that the radio purchased IS a GMRS radio. (2) Lack of simplicity in working with the FCC site. (3) Various viewpoints on not wanting to give the government anything. I'd say #1 and #2 are really it. If each radio came with a QR code that took people to a name, address, credit card number form, I think adoption would be a lot better. In other words, make it more obvious that it's needed, and make it really simple to acquire. You can't change attitudes easily, but you can help those who are willing to be helped. For me it's worthwhile getting licensed. I want to feel comfortable in using GMRS around town, up at the ski resorts, out camping, on road trips, and so on. I know that enforcement is almost non-existent, but I do gain some comfort in knowing that I'm doing the right thing.

I think the reason people care is because they paid and someone else didn't. It's just a matter of them feeling that if they are keeping the rules, why is nobody else? Yes, hall monitor mentality. I've thought about it. I paid my $35. I hear no call signs being uttered except for when there is a net in operation, or people working a repeater. And I do mean none. Nobody. Never. I never hear another person using a call sign on the GMRS / FRS frequencies except in formal nets or repeater use. Even some nets aren't identifying with call signs. There's nothing that can be accomplished by being grumpy about it. There are tens of thousands of GMRS or FRS radios that have been sold in the past few years within a 25 mile radius of me... of any of us. Maybe more than tens of thousands. One or two grumps are not going to stem the tide. Not even a few hundred. Remember the Internet around 1993-1994? It was well behaved (or at least conformed to a consensus standard). Spam was almost unheard of. Then ever fall a new set of students would get their school-issued accounts, and Usenet would blow up with stupidity for awhile until they were flamed into submission or departure from the medium. And then everything changed: The Internet became popular. AOL started sending out hundreds of million of CDs. There were news stories on the Internet. Books. Magazines. Globally the world was racing to get online. And these newcomers had no idea about, or no interest in stodgy convention. The net-police could flame all they wanted, but there was no stemming the tide of dumbing-down of the Net. All was not lost. It turns out that the Internet became a whole lot more useful when there were droves of people using it. It expanded into use-cases none of the old guard could have dreamed of. And of the unwashed masses? They're fine, it turns out. The real issue is the fraudsters, scammers, and hackers. So enforcement focuses in those areas. All this to say, there's really no point for an end user trying to enforce a policy that not even those who made the policy have any interest in enforcing. Let the FCC spend its time dealing with truly awful abuses, and leave the blister-pack kiddies and hard working businesses alone unless they're really, really causing harm.

Don't forget about the long tail. Any future where digital signals supporting 65k or 1M users on a frequency can be stomped on by bubble pack radios from Walmart transmitting on those same frequencies in analog, just won't work out. People are going to pull a set of FRS or GMRS radios out of their sock drawer five, ten, fifteen years from now and push "TALK" on the things, potentially disrupting a lot of people using a frequency for digital. It will take a long time to phase out existing FRS and GMRS radios. Case in point: I've owned a few sets of FRS radios over the years. One set got lost by an airline losing a suitcase. Another set had one of the two handheld units stop working, and for some reason I tossed them both. But sitting in a drawer three feet from me right now is a Motorola T6300 FRS radio. It supports 14 channels, has 38 CTCSS tones, and has some scramble mode. Using that scramble setting is not legal under current FCC rules, but when the T6300 was marketed (twenty two years ago), it must have been ok. My T6300 was manufactured November 2000. The point is that I have GMRS radios I bought within the past 30 days, but also a radio that is mostly compatible with my GMRS radios that is 22 years old. Let's say five years from now the FCC legitimizes digital transmission for voice over GMRS frequencies. I'll probably still have my 22 year old FRS radio, which will be 27 years old. And I'll probably still have the GMRS radios I currently own. But not just me. People all over the US have sets of these radios, and don't use them often enough to bother replacing them. This is to suggest, if the FCC were to introduce a version of GMRS that allows for digital transmission, it's probably going to have to be on a different set of frequencies from traditional GMRS. Even if the FCC were to eliminate GMRS today, those radios are still going to be keying up for years to come.

They're fun, inexpensive radios (well, my experience is with the UV5G, but practically the same). However, true scanners they are not. Even a 22 year old Radio Shack scanner will breeze through 22 GMRS frequencies in the time it takes a UV5G to get through five to seven. Modern ones are even faster. One of the key elements to scanning is covering the scanned frequencies quickly enough that you don't miss a lot. Dedicated scanners are good at that. They also often allow for easily turning on or off scan banks, quickly.

Radios that are set to output 50w are designed to do so when supplied with 13.6 or 13.8v, and at that voltage might draw 13A while transmitting. When the vehicle is shut off, the battery is going to supply closer to 12.6v when fully charged, and at that voltage, the radio will draw fewer amps; maybe 10-12A. And that means you will probably be transmitting at a little under 50w. You would have to measure to find out more precisely. The FCC won't approve a GMRS radio manufactured with the capability to transmit more than 50w at 13.8v. That means manufacturers aren't going to risk producing one that outputs 50w at 12.6v, because it might exceed the FCC limit when being run in a vehicle with an alternator putting out 13.8v. That means, if you want full power output from your radio, it needs to have a power supply that produces the correct voltage, and that can meet the amperage needs of the radio. For your 50W radio, you would want a power supply that can produce that full 13.8v, AND that can provide 15A current (which is probably what the radio is fused at).