dosw

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.

I just tested a sample patch for this CHIRP issue: https://chirpmyradio.com/issues/11372 With that tentative patch, it works correctly (you can set the scan mode correctly in CHIRP for this radio). I suspect the next time there's a CHIRP release, you will find that setting will begin working correctly.

Scan mode issue has been reported: https://chirpmyradio.com/issues/11372

Next thing to sort out: I *think* that when I upload from CHIRP, the scan mode settings aren't retained, or aren't uploaded correctly. Can someone confirm? Set the scan mode from TO (time-based, the factory default) to CO (carrier based) in Chirp. Upload to the radio. What setting does the radio get? This probably isn't a radio issue, more something that I would report to the CHIRP developer who worked on the driver. But first I want to confirm I'm not the only one.

Yeah, I checked the radio and CHIRP; I go up to 48 currently. I store the fully open set (no tones) in 1-30, then actual repeaters with their tones, then some family-use simplex configurations. We have configured one channel in the 1-7 range and one in the 15-22 range, the latter in several power configurations. When using the radios in known close-proximity such as assisting backing up a tow vehicle to a trailer, we use the lower-powered channels and stay away from the channels that repeaters may be using. When we need more simplex range we'll shift over to the 15-22 area. So that ends up getting me up to about 48 programmed channels.

I reviewed my pictures earlier in the thread, and it appears I do have entries in the 30s. 37 is the highest currently. I'll do some more experimentation with CHIRP tomorrow.

Glad the power issue somewhat worked itself out. I really can't speak for the Retevis software. I program mine with CHIRP, and with CHIRP I'm not limited to only 30 channels per bank. Can you share a screenshot of what the programming for you channels past 30 looks like in the Retevis software? Also, maybe give CHIRP a try. Don't forget that you have to download the code plug / image from the radio into CHIRP before you can begin editing.

Could even put it in memory slot 8 since you can't transmit there anyway.

And I ignored the part where you mentioned that CW is not synonymous with Morse Code. The HAM references often seem to use them interchangeably, but yes, CW is a carrier wave or continuous wave, with no modulation, whereas Morse Code is an encoding protocol that is often used in CW transmissions but can also be used in FM, AM, and SSB transmissions, or light transmissions, or banging on a heater duct in a prison.

We ignored the OP's description of the sound, though: "I hear what sounds like Morse Code, but in the form of static bursts, not tones,". I don't typically hear repeaters identifying with bursts of static. I suppose a simple explanation for that could be that the repeater is a bit out of range, and is identifying with CW, so we're just hearing a signal that was mostly lost along the way.

If a signal is transmitted at 5w, narrow band (12.5khz bandwidth), and another signal is transmitted at 5w wide band (20khz bandwidth), we would expect the quality of the transmission to be better in wideband, all other things being equal. We would also expect that a wideband receiver would hear a narrowband tranmission as being a little quieter, though I wonder if that's an accurate description; perhaps thinner sounding. I don't know. And a narrowband receiver receiving a wideband signal would sound a bit distorted as a portion of the signal would fall outside of the receiver's RF hearing. I think I'm understanding that. More bandwidth provides more capability for information-carrying signal to be transmitted and received. My question is about signal path loss. Does a narrow-band 5w signal have a longer signal path since that energy is focused into a narrower frequency range? One of the reasons that SSB is effective is a narrower / more efficient use of energy due to narrower RF bandwidth. Is that correct? This is just a question to satisfy my own curiosity. I realize that it probably has very little bearing on UHF/FM communications, but also... why?

I received mine within a day or two of you -- probably a couple of days earlier, also directly from Retevis, shipped from China. Given that there is no new firmware on the Retevis site for this radio, and that I received mine very close in time to you, I believe we have the same firmware. I don't know how to see the firmware version, though. First, let me say you're right about the manual, it's thorough but thoroughly translated in a version of English that is nearly incomprehensible without reading several times to understand the odd word choices. And it's also correct that the table of menu items refers forward in the manual to pages that don't exist. Fortunately the explanations are included in the manual, just not on the right pages. You are also correct that the memory slots 8-14 cannot transmit, which was called out in a different thread for this radio. Somehow in designing the firmware they thought that memory slots 8-14 were somehow significant, rather than understanding the actual FCC requirements which are based on frequency. You can put whatever you want in those seven slots -- 8-14, but you can only listen on them. On the other hand, with that in mind, you could leave those slots completely empty (CHIRP allows that), and the channel dial will skip past them. Then you can look at the radio as having 186 memory slots, not 200. However, I think your power levels concern might be incorrect. I've got the latest version of CHIRP right now (not "next", but the latest production version), and it does support multiple power levels. I'll include a screenshot. I have also looked at the code for the RA87 driver in chirp, and it hasn't received an update in the actual RA87 driver code since May 18, 2024. So I believe that whether or not we're both using the same version of CHIRP, we're probably using the same driver. Unless there's a code branch that isn't in the repository, that driver hasn't changed. And that driver supports five power levels. It is correct (from what I can tell) that the *manual* is wrong in stating that you can cycle through multiple power levels from the radio's keypads. You cannot. But you can configure them using CHIRP. I will also show pictures of the radio's display showing L2, L3, M, and H. In the attached pictures you'll see that I have GMRS channel 18 stored in multiple memory slots in the radio so that I can quickly/easily switch between power levels for that frequency by turning the memory selector. They're labeled FAM18x where x is L2, L3, M, and H. I use "FAM" or "FM" for "Family channel." That's just my own names for them so that I can quickly switch between them. You'll see at the top of each of those pictures, L2, L3, M, and H in small letters. That's the radio actually telling me in its own words that it is set to a power level other than L and H. In the last picture you'll see a screenshot of CHIRP where I have those "channel 18" configurations set up. And you'll see the drop-down menu showing them. Also here is a screenshot of the CHIRP code repository showing the power levels defined in the RA87 driver for CHIRP. This driver hasn't changed since May 18. I don't know about the Retevis software for this radio, as I don't run a Windows computer, and haven't bothered getting it set up using Wine under Linux since CHIRP does everything I need it to do. I've been meaning to provide some thoughts on this radio after a week of use, but I'm not at a week yet. Nevertheless: The manual is relatively complete but completely obfuscated with terrible translations and tables with page number crossreferences that don't match up. It was probably ported over from the Amateur version of the radio which would have had more pages in the manual. Power levels can only be set "low" and "high" from the keypads. But in CHIRP can be configured to one of five settings. It's a single-band radio. As such, it's configured for being able to listen to 400MHZ-480MHZ. There are versions of the radio configured for the 2m band and for a 300MHZ band, but they're sold by a different vendor under a different name. Memory slots 8-14 are listen-only, regardless of what is programmed into them. The sound quality is very good. I've gotten good responses from those listening to me, and I've also tested with a VOX-activated voice recorder so that I can listen back and hear the quality myself. Power levels are pretty close to accurate. Those complaining that it doesn't produce the correct power level (40w for example) are probably using it with a 12v battery only, not a 13.8v power supply, and not with a vehicle running its alternator, which produces more like 14.5v. If you run it at 13.8 it seems to be very close to 40w on full power. The mic is very light weight; I prefer the weighted feel of the MXT275, by comparison. Also the PTT button is a little less "sure" than I would prefer, but works just fine. Turning off the button-press and other beeps is the first thing I did. It's really annoying to have it beep every time the scan mode finds someone talking. The left and right sides of the radio each have 100 memories, of which you can transmit on 93. You can't transmit on memory slots 8-13. This is a bug in the firmware. But also, if the bug were in memory locations 94-100, would you care as much? If you put nothing in those slots, they won't come up as you turn the channel selector knob. It seems to have a scrambling mode which I think is not allowed by the FCC for GMRS. I haven't tested it to see if it's actually enabled. But it shows up in the manual, and in the menus. You cannot transmit on anything that isn't a GMRS frequency, even if you store the frequency using CHIRP. (A friend loaned me a dummy load.) It will give you the "no way" beep if you try. But you can listen to 446.0000 just fine. I've tested it with a 3dbi antenna and a 6dbi antenna, both easily reaching a repeater 63 miles away with good signal quality, and good quieting. I have line of sight to that repeater from my home (my home is at 5000 feet, and that repeater is about 6800 feet, with the valley floor at 4200 feet). I've also hit a repeater about 22 miles away, another about 15 miles away, and worked simplex within a couple of miles just to test. I have a lot more testing to do to see how the 40w compares to my old 15w radio. Probably less difference than one would think, though. I haven't found a way to turn off dual watch. So if you want the radio to not annoy you with flipping over to the other side as you're monitoring a GMRS frequency, find a never-used frequency, and put a squelch code on it so that it will leave you alone. The "Call" button is confusing, given the oddly translated instruction manual. It seems to be for storing frequencies into next-empty memory slots, but I haven't gotten it figured out yet. The memory labels are only six-characters max. All caps. I really like having a squelch dial rather than only digital settings. For my uses, it's a great value; I paid about $159 for it. And it outputs the power I want, and with scanning and channel storage features I wanted. It's a better radio than my old MXT275 in most ways except for size and the feel of the mic. Sound is better. Flexibility is much better. It has some quirks, for sure. But they're pretty easy to work around once you get it configured with CHIRP.

Do you have a data cable for your UV5G? I have two UV5Gs, but couldn't tell you how to program a repeater into them from the keypad. I know it's a two step process, but to me at least, I find CHIRP more intuitive. Here are the steps with CHIRP: Download and install CHIRP on your computer. Plug in the cable and turn on the radio. Select the Radioditty UV5G as the radio type under the "Radio" menu. Download the current configuration from the radio. In CHIRP, add repeaters and channels as you prefer. Upload it all back into the radio. I realize this is more than two steps. But it's convenient having everything on one screen where you can compare one row to another to verify you've got settings correct, and where you can easily organize your entries into segments within the radio's memory. A cable will set you back $8 to $14, and could arrive at your doorstep as early as tomorrow. Once you've gotten familiar with CHIRP, the familiarity will follow you to other radios in the future. For example, I recently obtained a Retevis RA87. It came with a cable, works with CHIRP, and I uploaded my channel lineup to it within minutes of installing it in my vehicle. Repeaters usually require an input tone to get them to listen to you. And they often send an output tone that you can set your radio to listen for. The input tone on the repeater prevents it from retransmitting a bunch of kids playing on dad's FRS radios a block or two away. The input tone causes the repeater to only open itself up to retransmit when the incoming signal is on the right channel, and transmitting the correct sub-audible tone. When it hears that tone on the frequency it's tuned to, it begins retransmitting on its output frequency. On its output frequency a repeater will usually also transmit a subaudible tone. This is for you, the listener's benefit. If you set that same tone in your radio, it will only open itself up to playing the incoming transmission if the tone is also heard. You are not required to set an RX tone. If you do not, your radio will play over its speaker anything it can hear on the frequency you're listening to. If you do set a tone, it must be the same tone that the repeater is sending, so that it can sense that tone and play over its speaker the incoming transmission. So to summarize: To send a transmission through a repeater you must be on the correct frequency, and you must have your radio set to transmit the tone that repeater requires. To listen to a repeater, you can set no tone (and you'll hear everything transmitted on that frequency), or you can set the repeater's output tone (and you'll only hear that repeater). If you set an RX tone on your radio, it has to be correct or you won't hear incoming transmissions. Your output (TX) tone must always be correct or the repeater won't listen to you.

Just found this: 60w amateur transceiver This appears to be the same radio as the RA87, with an Amateur radio firmware instead of a GMRS firmware. It appears to be a single-band radio, that allows one to choose between 134-176MHz/ 340-400MHz/ 400-480MHz. This model is called Recent RS-900, and is marketed as 60w. Yesterday I found some literature showing that the RS-900 can transmit at 60w/50w, whatever that means (I found somewhere a source that claimed 60w for VHF, 50w for UHF, but I can't find that now. Here's another link: https://www.anyradios.com/product/recent-rs-900-vehicle-mouted-radio/ In this link, you must select the version; vhf, 340-400UHF, or the 400-480 UHF band, which further supports that this is a single band radio, probably configured by its firmware. Using this link you can see the power levels that the RS900 should be capable of: https://twowayradioshoppe.com/copy-of-copy-of-vhf-marineb-transceiver-mobile-radio-rs-900-p4476598.html . In that link, the power levels are listed as 5/10/20/30/50. I think that the RA87's manual claims 5/10/20/30/40. So I don't know if the marketing is inflated for the RS900 (showing 50 max), or if the GMRS firmware for it is capping at 40w, or if the manual for the GMRS version is just wrong, since there are some reviews for the RA87 that claim people are getting more than 40w out of it. Anyway, it doesn't ultimately matter; 35w, 40w, 50w... all about the same thing.

All my computers run Ubuntu Linux. Chirp is easy to install on Debian derivatives; Mint, Mate, vanilla Ubuntu, and so on. I've been using Chirp there for a couple of years. You can also see the list of supported devices on the Chirp website, and even download all of the Chirp source code from GitHub to read through.

I was reading the CHIRP python code for the RA-87 and spotted a few interesting sections: 1: A listing of the actual (targeted) power level for each of the power settings (low, low2, low3, mid, high). POWER_LEVELS = [chirp_common.PowerLevel("Low", watts=5.00), chirp_common.PowerLevel("Low2", watts=10.00), chirp_common.PowerLevel("Low3", watts=15.00), chirp_common.PowerLevel("Mid", watts=20.00), chirp_common.PowerLevel("High", watts=40.00)] 2: The programming indicates that the "left" and "right" side of the radio have rather independent memories. This is also described a bit in the manual. But to be a little clearer, the radio is marketed as having 200 memory slots for programming, and while this is correct, 100 of them are the left side, and 100 of them are the right side. In the highly unlikely event that you would ever need more than 100 repeaters programmed into your device, for example, you would need to program some of them into the left, and some into the right. For GMRS this is not terribly significant; though there may be a few people who use a lot of memory banks, I suspect that most of us aren't using more than 100. If you need <100 total, then you could make left and right both contain the same things. But I suppose for those who want many configuration combinations for GMRS frequencies, you could burn through 100 and have to start using the left side and right side for separate configuration storage. 3: The CHIRP driver for the RA-87 sets "VALID_BANDS" to [(400000000, 480000000)]. It would be interesting to see what happens if one added more ranges to VALID_BANDS. (Bricking the radio is a possible "what happens", though.) This seems to align with what others have posted, that this radio will scan frequencies between 400MHz and 480MHz but not outside that range. It does look like tuning steps can be set to 5, 6.25, 10, 12.5, 15, 20, 25, 30, 50, and 100 (kHZ?). 4: The RA87StyleRadio class definition sets _gmrs = True. I imagine this results in allowing transmission on GMRS frequencies. In searching the code, I do see other radios setting _gmrs = True, or False, and see that other common settings for other radios are _ham, _murs, _pmr... with appropriate bands set in various ways. There is another thread on mygmrs where the question is asked whether the RA87 can scan 2m frequencies (and another comment that the manual doesn't mention any such capability). It is possible that this is simply not a capability of the RA87 hardware, but it would be interesting to modify the CHIRP driver for the RA87 to replace VALID_BANDS = [(4000000000, 4800000000)] with VALID_BANDS = [(1440000000, 1480000000), (4000000000, 4800000000)] ...and upload that to the radio, hopefully not bricking it in the process. I'm sure that adding _ham = True would cross over the no-longer-type-accepted line, though. And who knows if the radio would die a sudden death if one were to key up in 2m. For anyone who wants to look at the CHIRP driver code for this radio: https://chirpmyradio.com/projects/chirp/repository/github/revisions/d644af4b89c8edfe1b59f2f4aa929fc725056edd/entry/chirp/drivers/retevis_ra87.py

Correct. They would have to move the entire screw-in-rods section to below the bracket, and lower the height of the NMO threads so that the bracket's plate could become the backing plate against which the antenna's o-ring seats. Who knows if they'll get it right. Doesn't seem like that hard of a concept but people manufacture what the blueprints say without asking questions, and the blueprints were probably drafted by someone who was just delivering what was asked for, but without fully understanding the problem being solved. Again, the purpose got lost in the several hops between good intentions and implementation.

Interesting suggestion but it defies the explanations provided in amateur radio study guides (here's one: https://www.kb6nu.com/extra-class-question-of-the-day-effective-radiated-power/ ), and in Wikipedia (https://en.wikipedia.org/wiki/Effective_radiated_power ). Putting "not" in caps and adding an exclamation point doesn't make an incorrect statement true. But I could be persuaded that all the reputable sources of information are incorrect if a persuasive argument were made with supporting proof.

I bought a Nagoya GPK-01 ground plane kit, and discovered that it isn't weatherproof. Pictures attached... With the antenna fully screwed down to the NMO threads, the ground plane rods cannot be connected. With the ground plane rods connected, you cannot fully tighten an antenna on the NMO threads. In either case, the O-ring on NMO antennas is greater diameter than the NMO backing on the GPK-01 ground plane kit. I've tried this with an HYS SDN1-T, a Midland MXTA25, and a Midland MXTA26. Each one had an o-ring of greater diameter than the backing of the NMO mount, and each one extended low enough when fully threaded that the ground plane rods couldn't be attached. I reached out to Btech before returning the product because I wanted to make sure that I was not mistaken. Btech responded within a day to say that they were forwarding the pictures and description of the problem for further review. A day later they responded to say that they were going to be addressing this issue "at manufacturing", and would send me a replacement sample for evaluation after the corrections have been made. It'll probably be a little too late for my needs; I will just get a no-ground-plane antenna to put on the sailboat mast, and don't intend to lower the mast again for a few years. But I'm really happy with the outcome of the email to support, since it helped them to recognize a design deficiency, and because they do intend to correct it. Once I've received the replacement I'll post here about it. As I look at the pictures, it seems like the part that the rods screw into could be manufactured so that it's below the bracket, and the antenna could mate against the bracket itself.

Continue asking questions. Answerable questions are great. You didn't mention what GMRS handheld you have. Some models like Midland handhelds don't allow for removing the antenna. But in the GMRS realm that's less common. Nevertheless, before buying an antenna and an adapter, do make sure you are able to remove the one that came with the HT