Lscott

In an automotive application vibration might be a factor that could fatigue a solid conductor if it's allowed to move around a bit and not adequately secured. Also consider that the cable running from the pole to your house for cable TV is a solid conductor. Those cables hang up there for years with few problems.

About the signal strength difference there shouldn't be any between wide or narrow band. Many modern radios are now software calibrated, no more popping the cover and turning screws. What I suspect is something in the firmware was changed that affects the signal strength reading itself. Some calibration/scaling factor got tweaked besides the wide band narrow band setting. There might be other "tweaks" in the firmware as well to fix other issues you might not have noticed. Your comment about the audio is that your experience or just a "hypothetical" case? It sounds like the later. If so if the repeater is programmed for wide band TX and RX and you use narrow band to TX to the repeater the RX audio level signal will be low and TX on the output as such. Now a narrow band radio monitoring the repeater's output, which now has a low deviation due to the RX audio level being low, will look like a narrow band signal to a narrow band radio. The user will hear the audio at what they are accustomed to as being "normal", no real mystery.

Are you asking about the center conductor or the shield over the dielectric? If it's the center conductor it doesn't make much difference unless the cable is being flexed frequently. This could be an issue with a trunk or engine hood mounted antenna, especially the trunk mount, in which case the stranded center conductor might hold up better. If the antenna is mounted on the roof IMHO either one is OK.

I did about the same thing with 3 nearly useless Kenwood TK-3200 2-channel ProTalk radios a buddy gave me for free. He had no use for them. These radios "officially" have 56 per-configured frequencies you can choose from in the programming software or in the radio's firmware when field programing the radio. Non of the frequencies are for GMRS. Further there didn't appear to be anyway to set the TX frequency different from the RX frequency in the software either, so repeater operation was impossible. Using a hex editor, and some lucky guesses, I figured out where and how the RX and TX frequencies were stored in the code plug. Now I have them programmed for the local wide area GMRS repeater and a simplex channel. Now they are usable for something practical. TK-2200_3200 Brochure.pdf

That's why I did an FCC license search. Even if the license is now expired it would still be listed. That's not what I found, so the FRS radio suggestion by @wrci350 make sense too.

I did an FCC search on 462.5625 and 467.5625. I found only one listing, and the license was expired. It was not for a railroad. I have no idea why Radio Reference has this listed for a railroad unless it's an error in their database. https://wireless2.fcc.gov/UlsApp/UlsSearch/results.jsp https://wireless2.fcc.gov/UlsApp/UlsSearch/licenseFreqSum.jsp?licKey=1754132

My wild guess why this happens is due to the fact no license test is required, like Ham Radio where the above type of groups and activities are commonly found. Then, if some members are too cheap to even pay the $35 GMRS fee they try and use FRS radios. I agree with the points above with LMR radios. I'm, again guessing, that getting permission to use already licensed LMR frequencies by "affiliated" groups wouldn't be a big problem. I do not agree completely with GMRS "NOT to be relied on for life and death communications" in the event that local communication infrastructure is destroyed due to fire, floods etc. GMRS might be one of the very few ways the general public has available to maintain communications in a local area. In fact I think that was mentioned some time back in another thread.

Being TDMA with about a 50 percent duty cycle that works out to an average power of about 50 watts. Maybe that's how the FCC looked at it for the license grant.

No, but they do allow vanity calls like this for Hams. https://wireless2.fcc.gov/UlsApp/UlsSearch/license.jsp?licKey=806849 Note the Ham is a female too. You figure it out.

The first "miracle" required is just getting the FCC to allow digital voice modes on GMRS in the first place.

That's what some people have used for building a simple repeater using two separate radios. Best use of one is for a cross band repeater. Lets say between 2M and 70cm bands for Ham use. You can run two low power radios into one antenna using a duplexer. https://mfjenterprises.com/products/mfj-916b I believe you can get about 60db isolation between to two ports with the above model.

I seem to recall reading a few messages on other boards about problems with some repeaters not opening up due to the low volume of the access tone in narrow band mode.

I'm primarily a Kenwood guy but I do have several of the older Motorola XPR-6550 radios. https://forums.mygmrs.com/gallery/image/261-e451d5e2-f358-40dd-95a1-af106f7e8584jpeg/ Yes they can be programmed to work on GMRS. However I checked my documentation and non of the FCC certification grants show Part 95 on them so technically they are not legal to use. I have no idea if any Motorola commercial grade radios that will work on GMRS carry Part 95 certification. To start off with you should be looking for a radio that has it regardless of manufacture anyway. On the other hand a number of my Kenwood radios have Part 95A certification and are legal. The one I carry around lately is the TK-3170 Type-1. https://pdfs.kenwoodproducts.com/9/TK-2170&3170Brochure.pdf Another one that a few have as well is the TK-3180 Type-1. While the Type-2 will work only the Type-1 has Part 95A certification. https://pdfs.kenwoodproducts.com/10/TK-2180&3180Brochure.pdf I do have a collection of other radios some of which also have Part 95A certification. If you have questions about those I can help with that. https://forums.mygmrs.com/gallery/image/249-934916052_radiocollectionjpg/ Here's a couple of photos of the mid-tier radios I have. https://forums.mygmrs.com/gallery/image/254-tk-5320-1jpg/ https://forums.mygmrs.com/gallery/image/251-nx-300jpg/ This is a cool radio, will work on GMRS, BUT it doesn't have Part 95 certification, doesn't have an FCC ID either since it was never sold in the US! Bummer. Works great on the Ham bands for DMR and FM, which is why I got it. https://forums.mygmrs.com/gallery/image/255-tk-d300e-fmdmr/ https://forums.mygmrs.com/gallery/image/271-new-in-the-box-tk-d300e/

So in the case of that radio it does appear you can mix TX and RX frequencies so I off base on that one. I guess I should be more careful about making statements on radios I haven't really used. Thanks for pointing it out. In any case one can use that radio and try out the split frequency operation for fun.

VHF marine HT’s might be the way to go as long as they are used on the water. They are license free as far as I know. Many if not all will float if dropped into the water. Something a GMRS HT likely won’t do. Nothing worse than watching a $100+ radio sink out of sight.

You advocating the use of uncertified radios on GMRS? I'm not. Also this part I guess you missed, "the cheap frequency preprogrammed radios", does not apply to the UV5R type radio since it is freely frequency programmable. Radios such as the 805, 905, 935 and similar from other manufactures etc. have preprogrammed TX and RX frequencies you can't modify and are commonly used for GMRS.

It's also not Part 95 certified. I'm talking about radios certified to use on GMRS.

I would venture to say a number of people have operated in an illegal manner, modes, power etc. a few times or routinely. I would hope they know the rules and understand the consequences if the FCC notices. At least they are smart enough, most of them anyway, not to publicly advocate or mention what they are doing, it sets a bad example for the newbies.

If you wanted to keep someone from using your repeater with the cheap frequency preprogrammed radios then picking a non standard frequency split would do the trick. Since the rules don't require one to use a 5 MHz split you're free to pick from any of the 8 TX and any of the 8 RX frequencies for the repeater. The only radios that will work in that case are modified radios and commercial Part 95 certified radios which you can independently set the TX and RX frequencies. Also the same idea will work to frustrate simplex jammers. Radio one will TX on F1 and RX on F2. The other radio will TX on F2 and RX on F1. Both frequencies are legal simplex channels. Each user can have several channels programmed up with different combinations of TX and RX simplex frequencies and switch between them, memory channels, as conditions demand. To do this with more that two radios is not as simple and would likely require some method to scan several channels very rapidly, a programmable home or priority channel feature etc. As far as I can see there is nothing in the rules that prohibits this either. So long as your operation is not causing interference, as you pointed out, it should be OK.

People need to read the rules before believing some of the stuff they get on the 'net. The rules don't limit the number of repeaters, just the number of frequency pairs, GMRS "main channels", they can use, currently the rules list 8 RX and 8 TX frequencies. As a side note I don't see anything that requires the RX and TX frequencies to be exactly 5MHz apart either so long as you use one of the 8 TX and one of the RX ones listed in the rules. https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-95/subpart-E/section-95.1763 You can have as many repeaters as you want on a frequency pair so long as the frequency is shared with other users.

https://www.youtube.com/watch?v=HNLQ-O-Qx3Y

By an inline attenuator. Put that on the output. I got this one used for about $50 a while back as an example. I also have a set of low power Weinschel's to use with an old HP power meter. Narda Fixed Attenuators.pdf Models 1 and 2.pdf HP432A Specifications.pdf

Try the attached files. Canada VHF LADD Channel List .pdf CB Radio Around The World.pdf Civil Air Patrol.pdf Common Itinerant and Business.pdf Freenet-2.pdf KDR444.pdf 1156812829_PMR446WhitePaper.pdf Railroad - Scanner Frequencies and Radio Frequency Reference.pdf VHF Marine Frequencies - 1.pdf

I looked it up since the official RR frequency list can be found in the attached file and the ones you listed didn't look like what I expected. Of course there could be additional ones assigned by the FCC for special uses. Got curious and had to check. I have a code plug written with all of the official VHF FM and NXDN digital railroad channels for a Kenwood NX-200 radio. The portable radios used mostly by the railroads are from Kenwood and Icom. https://comms.kenwood.com/common/pdf/download/02_NX-200G&300GBrochure.pdf I haven't really tried it yet. If anyone is interested I've attached a copy. It also has some of the Ham 2M simplex channels, MURS and the VHF NOAA weather frequencies too. With 512 available channels it wasn't much of a squeeze. Railroad - Scanner Frequencies and Radio Frequency Reference.pdf NX-200 Railroad 20220422.dat

Very unlikely. If one wants VHF access use MURS. Want HF access use 11M CB radio. Want more channels, power, repeaters and bands get a Ham license. That's going to be their logical response.