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Earlier I attributed this to a school's drop-off line, but I just hadn't listened carefully enough. It's a mechanic: mechanic.mp3 This goes on all day, from a few minutes before 8am, until around 4pm. Channel 18. It's probably a PepBoys (3.1 miles). I hear them from my kids' school, too. That's over 3 miles in a different direction. I suppose it's possible that it's not even handheld, in which case it could be any one of hundreds of mechanics across the valley. Too bad they're using channel 18. My guess is they could do this all over 500mw on channel 8, and not muddy up a repeater output frequency with this. On the other hand, I wish everyone were so enthusiastic about their work!

You probably mean MXTA26, which is still my primary antenna on the vehicle. I'm using the Comet in a different application where I wanted dual-band without compromising tooooo much in GMRS. It's the first one that gets my antenna count in this application down to one. If I had to rank the antennas I've tried on GMRS performance I would go with Midland MXTA26 (6dbi) > Laird TE B4505CN (5dbi, NGP) > Comet CA-2X4SR-NMO (6.2dbi) > HYS SDN1-T (3dbi) > Midland MXTA25 (3dbi) > Midland MXTA13 (2.1dbi). But that's just ranking how I sound from 3-miles away on simplex as well as some signal reports from distant repeater users. Each of these have their own strengths. The MXTA26 is just a good solid antenna, 32 inches tall. The B4505CN is a pretty solid "no ground plane" antena. Good signal reports, good SWR without a ground plane. The 2X4SR is not bad at GMRS, and also good in MURS and Marine VHF ranges. The SDN1-T is only 17.7 inches long, and works pretty good for closer-in repeaters, not great over longer distances across the city. The MXTA25 is so compact and doesn't draw much attention, still working alright given its form factor, and the MXTA13 is perfect to keep in the glovebox or put on the packing list in case of an NMO mount failure. Lightweight, it travels easy.

Well, for that to go anywhere it would be a year or so of petitions, a couple years of hearings, and a couple years before manufacturers start making radios with the new pairs (of course those with chirp or proprietary software for programming will not need to wait). But even with new pairs, and software, a lot of radios aren't going to transmit outside of today's GMRS frequencies. They're not supposed to be easily modifiable, right?

Mine arrived today. I tested it on my vehicle; at 462.xxxx and 467.xxxx it produced SWRs between 1.1-1.35:1. It was better than expected. Mounted on a magnetic mount on my super-sketchy window air conditioner it produced SWRs between 1.01 and 1.3:1 in the 462&467 range, and 1.01-1.5:1 in the VHF range. I haven't tested fars yet, but really I don't need to. It's going to be just fine for my needs. It's so true that this is a big, heavy, ugly antenna, by some definitions of ugly. I don't mind it. I also tested it on both MURS and GMRS frequencies mounted on a camera tripod with a GPK-01 ground plane kit. With the kit its SWR at MURS frequencies was still 1.1-1.3;1. And at GMRS frequencies things got a little worse, like 1.7-1.8:1. Without the GPK-01 ground plane kit, mounted on a camera tripod, it was more like 1.7-1.8:1 in the VHF range, and 2.4:1 in the GMRS range. Great antenna. I'm glad I got it. At some point I'd like to do a shootout of the antennas I've collected: MXTA13, MXTA25, MXTA26, HYS SDN1-T, Laird TE B4505CN, and this CA-2X4SR-NMO antenna. If anyone has parameters or methodologies they'd like to see, let me know. I can toss the GPK-01 ground plane kit into the mix as well, if we want. For mounts, I have that kit, plus a hood lip mount (positioned such that I have at least seven inches of vehicle body steel all around), and a magnetic mount.

I connected the SWR meter to a one-foot RG8X coax connected to the back of the radio. And the antenna side is connected to the MXTA26 with the hood mount NMO connector that comes with way too much of whatever cable Midland supplies with that hood lip mount. But again, near 40w at the 462+ range, and 27w on the 467+ range, the repeater inputs. Anyway, it barely matters, or doesn't matter. Just a weird thing. I'll need to test with a dummy load sometime.

Why does your poor quality video show a DC power supply, then? This is what is shown in the video: https://www.amazon.com/Pyramid-PS9KX-Universal-Regulated-Converter/dp/B0002BA570?th=1 That's a DC power supply, supplying DC power from the AC mains. But to respond to @WSBR383, that power supply is 13.8v, which is outside of the specs he showed us for the GMRS-RPT50. So something that @justin10 hasn't grokked yet is that he's powering the repeater 1.3v above its specified input voltage range. I rather doubt that matters so much, but it is one thing to consider. Does the problem go away if you hook it directly up to a 12v battery?

You get to decide whether you see chronological or vote-based sorting:

Reviews for this antenna seem to be generally very good. It comes in two versions: the PL-259 version, and the NMO version (CA-2X4SRNMO). Both versions are foldable. The antenna is marketed as broad multi-band, with a pretty wide VHF frequency range, and a wide UHF frequency range: Dualband: VHF and UHF 140-160 MHz / 435-465 MHz VSWR: Less than 2:1 / Gain: 3.8/6.2dBi / Max Power: 150W FM My question is how does it perform at 467.5500-467.7250. It's supposed to achieve <2:1 SWR at up to 465MHz, but 467.7250 is almost 3MHz outside of that spec. My MXTA26, mounted on my vehicle, gets a 1.4:1 SWR in the 462.xxxx range, and 1.1:1 SWR in the 467.xxxx range. So it's almost impossibly good for working repeaters, as far as mobile antennas go. How does the CA-2X4SR compare? https://www.amazon.com/Comet-Original-CA-2X4SR-140-160-435-465/dp/B00HVGQZ9G My Laird/TE B4505CN (5dbi) is in the 1.15-1.35:1 SWR range across the 426.xxxx and 467.xxxx range. And the HYS SDN1-T (3dbi) is in the 1.1-1.3 SWR range throughout the 462.xxxx and 467.xxxx frequencies, also when mounted on my vehicle.

Capital (15 miles) and Ogden (43 miles) are no problem for me. I'm a mile west of Wasatch near Little Cottonwood Road (near the mouth of Little Cottonwood Canyon) at 5080 feet elevation. The Capital repeater is on Ensign Peak, so good elevation, and the Ogden repeater is on Mount Ogden -- also good elevation.

I tested today with my SWR meter again, and found the power output levels to be relatively higher than predicted in the software. CHIRP, for example, lists the levels as: L/L1: 5w L2: 10w L3: 15w M: 20w H: 40w In reality they came in at the following, on channels 15-22: L/L1: 4.9w L2: 10.8w L3: 18.5w M: 26.2w H: 38.4w That, with an SWR of <1.4 with my MXTA26 antenna. And that was with the vehicle shut off, so the input voltage was 12.5v, not 13.8. At "engine running" voltage (14.3v on my vehicle) it should be very close to 40w on high. However, when I switch over to repeater channels, the output power on high drops to 29w across the board. Something about the 467.xxxx range that the radio doesn't want to output close to its full 40w. But also, in the 467 range, the SWR with the MXTA26 drops to better than 1.1:1 in my installation. It probably doesn't much matter that I'm losing 10w transmitting on repeater inputs, but I'd still like to know why.

Anyway, that's not GMRS. On GMRS I enjoy when I hear traffic on the Promontory repeater, because I believe that's 63 miles from my house, and with the right $60 antenna, sounds like it's next door. That's on 462.700 / 21R. I've hit it with a UV5G with an external antenna, though I get a lot better signal report when I hit it with a mobile at a little higher power.

I picked up this one: https://utahvhfs.org/cgi-bin/rptdtl.cgi?Nr=366 It's listed as "Scott's Peak", which I think is actually Scott's Hill, northeast of Brighton, west of Park City. But the repeater list calls its location "Brighton." Snowbird is different: https://utahvhfs.org/cgi-bin/rptdtl.cgi?Nr=124 -- A 2m repeater on Hidden Peak.

You got some winners, there. Last night on a 70cm repeater I overheard a net that was mostly mapped over to VHF, with people checking in from Vegas/Nevada, Montana, Arizona, Utah, and Idaho. The strange thing was that the repeater I was receiving this net on was based at Brighton, Utah, which is a ski resort; not one of the "big" repeaters near the city. They must have a very well placed antenna to be able to tie into a relatively spread-out network of repeaters from 19 miles up the canyon in the mountains. The "tarzan call" guy is pretty annoying. Every morning from about 7:50 through 8:00am he shouts sort of singing war cries on GMRS 18. They're mostly impossible to understand, though they mention the time. I think today I heard him say "Ashton it's almost 8AM!!!" (in a singing / shouting tone of voice). And then a little later, "It's 8:00am, Ashton!!!" (along with more chanting and singing). I think he is his son's alarm clock, and GMRS or FRS is his tool. But the signal is strong for several miles. I'm often driving my kids to an activity they participate in daily at this time, and I hear him equally well whether I'm a few miles to the north of my home, or a few miles to the south -- stronger than I would expect FRS to carry. If you're this guy, and you're reading this, please switch to channel 12; that sort of thing doesn't need to be transmitted at more than 500mw.

I had some old 2001 FRS Motorola radios where, all devices configured with the same call tone could be made to vibrate when the call tone came through (even with volume off). Those were the only radios where the button potentially served a purpose other than to amuse seven year olds.

I like this one: https://kv5r.com/ham-radio/coax-loss-calculator/ And it agrees with your calculation, assuming a 1:1 SWR. As I tinker with different antennas and cables, I find that I get 1.1-1.5 SWR with all of my antennas when properly mounted with a ground plane. So if you have a perfectly acceptable 1.5SWR your power to the antenna is estimated to be 5.7 on that calculator. The calculator doesn't take into account loss through connectors. There will be a little, there. If you put a 5.1DBd antenna on there you would have an ERP of about 18.5, again minus a little for connectors.

What's 'pro' about this one versus the UV-5G? Just curious. It looks exactly the same.

Event coordination -- not big professional events, just school and summer camp kinds of events. Lots of road construction: "The last car through will be the red Nissan. Ok clear to send." Lots of building construction: Pasame el martillo cuando termines, por favor. or Drop that load of lumber along the side of the property. A local flower nursery: Can you unpack the pallet? We have someone here who needs potting soil. Some local go-kart raceway. Lots of kids playing walkie-talkie. Roger beeps, call beeps and chirps, talking over each other, shrieking, feedback. Some guy on 18 doing a Tarzan call followed by "Good morning everyone!" every morning around 8am, with no response. A guy going hour after hour on one of the local repeaters. Nothing wrong with that -- if people are engaging and communicating with him, it must be interesting to them. But it tends to tie up the repeater between two people talking almost back to back without pause for a half hour or an hour at a time. Nobody knows the repeater's owner, from what I've heard. But it is extremely well placed, with a strong, high quality signal that covers the entire metro area. Radio checks and signal reports. Repeater nets, and simplex nets. The simplex nets are local neighborhoods doing a sort of emergency preparedness drill every week. DXing repeaters -- Last week there was a guy who went way out onto a mountain in the "west desert" to do some HF DX-ing, but also checked in with a local repeater to run a net just because it was interesting to see how it would work out. But the overwhelming majority of what I hear is kids playing with radios, and construction of some form. Why do I listen? More interesting, while driving around, than listening to the FM stereo radio in my car. And somewhat mind-numbing background noise as I work from home as a programmer.

I'm just following up to confirm, the 6/14/2024 release of Chirp Latest contains the bugfix for the RA87 scan modes. If you start up Chirp today, it will suggest downloading the newest version, and that version will have this bugfix. When I looked over the code I saw that it was probably a one line fix in the driver, suggested the patch. The author acknowledged that it was suitable, applied it, I tested it, and then they rolled it out and closed the bug report.

Your other posts mention a couple of Wouxton radios; KG1000G and an 805G. Those are both nice radios, but I've never seen a two-way radio that scans anywhere near as fast as a dedicated handheld or desktop scanner like even a basic Uniden BC125. A scanner like that would scan through 100 memory slots in two to four seconds. Things slow down if there's traffic, of course, and even if you've got PL tones set on the scanner, it has to pause long enough to hear the tone. So there are limits. But a dedicated scanner from 20 years ago will beat most two-way radios in scan mode.

It would be interesting to see a comparison of these inexpensive dual-watch, programmable, 40w GMRS radios. The Radioddity DB40G, and the Retevis RA87 have a lot of similarities, but it looks like a lot of differences too. And the price is comparable. The RA87 does come with a data cable, though. Both models can be had for less than $179. Both have about 200 channels. Both are single-band, and 40w claimed. Both are dual-watch. And of course both are GMRS. Is that where the similarities end?

Nagoya / BTech shipped me an updated version of the GPK-01 to test. The new version made the following changes: The NMO threads are longer, so that the antenna fits more tightly against the thread base. The ground plan rods don't have the crosshatch pattern, and have a thinner diameter where the crosshatch was before. This makes them a little harder to tighten, but they take less space. This also allows the antenna to bed more securely against the NMO threaded male side. They didn't provide any kind of backing plate to match up to the O-ring on the back of NMO mounts. But at this point, with some diaelectric grease it should be a good enough waterproof connection to be acceptable for my needs. One may still want to caulk with a marine silicon or something like that. But it's going to be good enough now.

I have LMR400 ready to fish through the mast, through the deck, and aft to the radio inside the cabin. I can do it in a single run with a water-tight through-deck fitting. My marine VHF uses RG8U, but at VHF frequencies that seems to be sufficient. My boat's GMRS radio is my 15w MXT275, recently put out to pasture when I got a Retevais RA87 to take its place in my vehicle.

Marine VHF is in the 156-160MHz range. The common approach is, for power boats, a 6dbi or 9dbi antenna at the transom (smaller powerboats) or on the bridge (larger power boats), or a 3dbi whip at the mast head for sailboats. And the conventional wisdom is that a masthead 3dbi stainless steel whip will be more reliable under sail (while heeling) than a 6dbi or 9dbi fiberglass. I have a marine VHF, but it's mostly not legal to use it for ship to shore (not that anyone's going to care much around the Great Salt Lake, but this is an excuse to put up a GMRS antenna too) My rationale for putting GMRS on the boat is that (1) I can. (2) Repeaters are available. (3) Ship to shore is allowed on GMRS. (4) It's fun to try things out. I do have a 3dbi gain Marine VHF whip at the top of the mast, too. My mast is about 29.5 feet long, and sits atop the deck which is about 4 feet above the water line. So 33.5' over the water from masthead to water line. My supposition is that is too great a distance between the antenna and the water to be able to consider the water a ground plane. But I could be wrong. I do think I'll go with the MXT-A26 up there, and will use a putty-tape to seal around the set screws and around the connectors, along with some diaelectric grease anywhere water might intrude. There are two repeaters that are pretty much ideal for allowing communications between the boat and my home. The Promontory Point repeater is 63 miles from my home, but situated very close to the lake, 2000 feet above it. I have line of sight from home to that repeater, and also from the boat to that repeater. There's also the Salt Lake Capital Repeater which is about 25 miles from my home, and 25 miles from the middle of the lake (in different directions). I also have line of sight to it from home, and the southern 1/3rd of the lake has line of sight to it. As you go North on the lake it's obscured by Antelope Island, though.

Overthinking is my pass time. And it won't be done until the motor is done being serviced, which is a prerequisite to getting over to the mast crane to raise the mast. Until then I can experiment and play with options because it's interesting to me.

Currently I have three antennas to choose from for a masthead installation (I own these three): MXTA-26: My favorite antenna. If this goes on my sailboat mast head I'll have to buy another of the same, though I don't mind. Advertised as a 6dbi antenna. HYS SDN1T: Advertised as a 3dbi antenna. This one is surprisingly bad. More on that in a minute. MXTA-25: Ghost antenna. For those who dislike this antenna, I'll say it works quite well. Better than the SDN-1T by a fair margin. (Not in the running) Midland stock mobile 2.1dbi magnetic mount antenna. Because it's not NMO it isn't going to work on the masthead. Sailing may be a problem for higher-gain antennas: While motoring or sitting idle, the MXTA-26 would be a fantastic choice for a masthead installation. However, under sail, I might be heeling 5 degrees to 25 degrees (often a long time at 10-15 degrees. So I'm trying to decide if this will be appropriate for the masthead. If it is not going to be appropriate, based on its radiation pattern, I'll probably have to go back to the drawing board and order something else. Why not the HYS SDN-1T? I actually bought this one specifically to use on the masthead. But then I started testing it. Ugh, it's not good. Today I set up a voice recorder hooked up to a UV5G at home, with the MXTA-25 magnetically mounted to a window air conditioner at home. Then I drove four miles away, 350 feet below, with a couple of bluffs creating some line of sight issues, and tested several options. 1: The MXTA26 attached to my mobile Retevis RA87, testing at 5, 20, and 40w. In every case this antenna performed very, very well. At 5w the quieting wasn't as good as at 20w and 40w. But I couldn't hear any difference between 20w and 40w, and transmissions were crystal clear. Again, this is advertised as 6dbi. 2: The HYS SDN1T: Attached this to the same Retevis RA87, and again tested at 5, 20, and 40w. At 5w it was hard to make out. At 20w and 40w there was a lot of background hiss; not very good quieting. It just didn't sound very good. Again, this is advertised as 3dbi. 3: The Ghost antenna (MXTA25). I wouldn't mind putting this on the masthead. I'll have to repeat the tests mentioned here first. But it's in a plastic housing, and I don't expect that it would be as trouble-free sitting on a masthead for a few years. For now I'm ruling that one out just because I think its plastic housing would deteriorate over years of sitting up there exposed. 4: The "stock" Midland small magnetic mount antenna. This is listed as 2.1dbi. I connected this to another UV-5G and tested at full power (<5w). It sounded BETTER than the HYS SDN-1T, even compared to the HYS antenna being used at 40w. So now we have a definite loser. The HYS SDN-1T is WORSE than the little almost throwaway magnetic mount antenna that Midland includes for free with all of its mobile radios. The conclusion: I can't put that on my mast. But that brings me back to the original issue: Will the propagation pattern of the MXTA26 be awful when I'm sailing and heeling a few degrees? If so, I'll have to resume my search for a good masthead antenna that is more in the 2.1-3dbi range, that works with an NMO mount which I've installed on the masthead. Is there an online calculator, or a formula that I can use, to see how propagation is impacted by antenna angle, or what the propagation is for a given angle above or below "level" for an antenna based on its gain? ------ Update later in the day: I had some time to swap around and test using the HYS SDN-1T as a receiving antenna at home, and then comparing the MXTA25 to the MXTA26. From one location about 4-miles out (where the MXTA26 previously had no problem getting through at any power from 5w to 40w), I compared the A25 and A26. The A26 performed very well, fully quieting at 15, 20, and 40w. Background noise at 5w. Then I swapped in the MXTA25. I was quite noisy at 40w, and from this location it didn't propagate well enough to break squelch at 5, 10, 15, and 20w -- only at 40w. I tested again about 2 miles away and found the MXTA25 to be adequate at 5-40w with quite a lot of background noise at 5, 10, and 15w. And the MXTA26 was crystal clear at 10, 15, 20, and 40w, with slightly elevated background noise at 5w. So if I were to rank their effectiveness: MXTA26 - Very good simplex at 4 miles for 10-40w, some background noise at 5w. HYS SDN-1T - Not great at 4 miles even at 40w. Usable but poor at 5w at this distance. Midland Stock miniature magnetic mount antenna included with MicroMobile radios - About the same as the HYS SDN-1T symplex at 4 miles. MXTA25 - Not usable simplex at 4 miles. Reasonable for simplex at 2 miles. There's really no comparison, though. The MXTA26 outperformed the other three by a long shot. And I was surprised that the MXTA25 did as poorly as it did at 5w at 4 miles distance. The terrain isn't great; the receiving antenna is about 350 feet above the transmitting antennas, with several hills obstructing line of sight somewhat. Pretty good real-world test though.