Lscott

So did I. Also had the matching printer that used the aluminum coated paper.

The few XPR6550’s I got used were missing the side port covers. I was at a Ham radio flea market a while back and spotted a bag with 4 or 5 of them inside on a table. The guy was selling mostly Motorola gear. Unbelievable he just gave me the bag for free after I inquired about what he wanted for them. He said he had no use for them. Who says there aren’t any nice people around anymore, there are!

Many, if not most, use the Kenwood "K" type side connector for programming and other accessories. My guess is when the Chinese needed to "copy" something and wanted a standard to follow they picked Kenwood, which BTW also used the reverse SMA antenna connectors, long before the CCR's did. I'm guessing that's how it all got started. The number of Kenwood radios for commercial use far outstrips their Ham portfolio. I guess if you're going to copy something as a standard pick one with a large market presence. For me it's really convenient since I can pickup the cheap accessories used for the CCR's and use those on most of my Kenwood radios. If you leave the port cover off they can get water and dirt/dust inside of the radio. That's the main disadvantage. Not all of the Kenwood radios use that "K" type side port. A surprising number use a multi-pin side port like you see on Motorola radios, but of course they won't use the same accessories. These ports are more environment proof since there are no openings into the radio. Unfortunately one of those pins has a live +5VDC supply on it, used by some of the GPS and noise canceling microphones. Shorting that pin out isn't healthy for the radio. If the port is not being use the cover should be installed. Now about the reverse SMA connector. Some of the older Motorola radios use them. However they are not "exactly" standard. If you look at a real Motorola antenna verses the one used on the CCR's and Kenwoods you'll notice the tip of the screw connector for the center pin is flush with the end. On the other antennas it's typically recessed a tiny bit. If you try to screw it into the Motorola radio the center pin in the socket won't slip into the connector on the antenna because the threaded barrel section bottoms out too soon. I'm sure that was done to get the aftermarket parts business for antennas. The four areas on a radio that frequently seems to get broken, or lost, are belt clips, antennas, the knobs and side port covers. People like to use the antenna or top side knobs to yank the radio out of the pocket or off the belt, particularly the antenna. The belt clips break when twisting the radio while trying to take it off the belt, or the radio will catch on something, cloths etc. and rip the radio off. Side port covers, well I guess that's the first thing that's lost after programming the radio, or attaching that external speaker mic.

This is what a Michigan Ham call sign plate looks like.

Never thought they would beef up the IRS with so many people, but surprise, they did. Am I "giddy" at the prospect of a clamp down by the FCC? No. Remember when Hams were begging the FCC to start enforcing Part 97 reg's? Nobody thought "anything" would happen, it did, not much, but there was some action taken. The way things are now I wouldn't dismiss anything, however, we're living in the Twilight Zone at the moment.

The FCC doesn't have the man power, but they did spend $80Billion on 87,000 more IRS agents. Things could change.

Good practice suggests using no more power than necessary to establish good communications. If you can get in to the repeater with only a watt or two I would do that. It keeps the hand held radio cooler and the battery pack will of course last longer.

The software should give you the option to save the radio's setup/memory programming file to disk. That's the file you want to open with the editor.

If you look at the screen shot he provided, copied here, you'll see three pairs of frequencies, for three different channels in the editor. He boxed one of the two frequencies, in red, for a pair which he determined was the TX frequency for that particular memory channel. Since initially both RX and TX were set the same that's why they look like a duplicate of single frequency, but in reality they are the discrete RX and TX settings. This radio does not use a firmware that assumes a single frequency with an offset model, typical for some Ham Radio gear. It REQUIRES two distinct frequencies, one RX, and one TX, for each memory channel. This is common for many many radios, particularly for commercial models and their derivatives. Having hack a number of Kenwood radio specific codes plugs myself I've seen the same thing using a hex editor.

I guess that’s possible. You don’t have access to the firmware code so you can’t be sure exactly what they did. Maybe some more experimentation might help to figure it out.

Yeah, if you look closely at his screen shot of the editor you will see several pairs of frequencies, one pair for each programmed channel. All he did was pick the second of the two in a pair, the one he wanted to alter, and changed it from 462.xxxxx to 467.xxxxx to get the repeater input frequency. The only down side to hacking code plugs like this is when you need to make a change to the frequency. If it's one of the hacked custom frequencies you're back using the editor again. Not real convenient but it works. Not all radio's code plugs are this simple to hack. A few use various types of encryption to try and prevent this sort of thing. I figured that out on some of the Kenwood radios I have. After decrypting the code plugs a few interesting items were found like model numbers, embedded radio serial numbers, programming software license install keys etc. I was also able to see the normally hidden radio write protect password, if used in the software, in the clear.

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/