Lscott

That would be a big improvement. Just about, if not all of the commercial radios where I looked at the schematics, use some type of tracking filter on the front end as well. If somebody has access to the service manual for this radio it shouldn’t be hard to tell if the same was done there. From some comments made on another site I believe the Anytone D878UV, and likely the D578UV, have tracking filters on the receiver’s front end. Very likely the reason why they cost more and perform better that your typical $20 CCR. In any case a super heterodyne design will help with image rejection if the IF frequencies are picked right.

I would wait until someone else buys one and uses it in a typical urban environment. I suspect due to the small size this is likely just another inexpensive radio-on-a-chip design with a fancy screen and more power output compared to an HT. Where these radios really fail is in the receiver section. For example I got a TYT-8600 new for $100 a couple years ago. On UHF the receiver selectively is poor. I get very strong signals showing up on various FRS/GMRS channels I know for a fact is not there, confirmed by simultaneously monitoring with a good commercial radio. In my case it was a high power police dispatch system 10 miles out and a DMR repeater at a hospital about the same distance the other direction. Remember if you can’t hear the other station because of a poor receiver then your transmit power makes no difference.

You can find these on line at places like Amazon, eBay etc. I think I got my second one off an eBay seller.

I would suggest trying this one out. https://www.dxengineering.com/parts/pry-al-800 I’ve used these on a short run of RG-58 coax. They work fine without a ground plane. The match on the Ham bands is pretty decent. On MURS and FRS/GMRS it’s up a bit but I think it was still under a 2:1 match making it usable.

https://www.manualslib.com/manual/779398/Kenwood-Tk-880.html https://all-guidesbox.com/download/499649/kenwood-tk-880-series-service-manual-70.html

Does anybody use one with an external antenna? It seems Motorola took a good radio and sort of mucked it up by using that funky stud type antenna connector. Looking at some videos, showing a stud to BNC adapter, a thin copper foil ground strap is required to be run from the inside edge of the antenna well, over the top rear edge of the radio down to the mounting screw for the belt clip. That screw is in the aluminum chassis providing the ground connection for the adapter. When the adapter is screwed in the “shell” makes contact with the copper foil ground strap completing the coax shield connection to the ground side of the radio. This doesn’t require any permanent modifications to the radio or interferes with the normal use of the rubber duck antenna. I really don’t like this since the length of copper foil from the antenna well to the grounding screw likely results in a significant impedance bump. However without it the coax just turns in to one long grossly mistuned antenna. At least with the older XPR6550’s I’m going to experiment with they use fairly standard SMA antenna sockets on the radios. I have a bunch of SMA male and SMA female to BNC adapters I can use.

If I got one for free I’m not complaining. Maybe some future update might eliminate that restriction. Likely the two that I would use are DMR and P25. The radios are very expensive and the software requires registration with license files etc. For a business they can deal with it. For a private individual for hobby use, not going to happen, not me anyway. I have a used XPR6550 VHF radio I just purchased for $75 off my favorite auction site coming. I have a used XPR6580 for $45 that should be shipping in a day or two. There is reportedly a way to put it on the Ham 33cm band. That’s why I was interested Unfortunately it seems I need the conventional version of the firmware. The radio looks like it has the trunking firmware which I’m lead to believe won’t work with the code plug hack to put the radio on 33cm. Until I can scam up the right firmware the radio will go into a storage box. I would also like to get my hands on the current version of the XPR6550 firmware for the VHF/UHF radios. Now that I seem to have a functioning version of the Motorola Mototrbo software I going to experiment with a few of them.

We can kiss and makeup. No harm done.

Yeah, I understand that. If somebody gifted me a nice Kenwood NX-5200, 5300 with all three digital modes, NXDN - DMR - P25, enabled I wouldn’t turn that down either. https://comms.kenwood.com/common/pdf/download/NX-5000_portable_Specsheet_K_02_prnt.pdf

About radios, you get what you can afford and fits your operating requirements. I don’t care if someone is using a $20 CCR or a $5,000 Motorola. I use primarily Kenwood radios, I do have a small number of Chinese ones, not because they are better, it’s just a personal choice.

Noted.

I don't make the rules. I just offered an explanation. One is always free to contact the FCC and petition for a rule change. It's been done many times before. https://www.law.cornell.edu/cfr/text/47/1.401 https://www.fcc.gov/about-fcc/rulemaking-process

I've looked briefly at those. I might consider getting one or two if I can find a super good deal just to experiment with them. I don't have any 900 MHz radios. I looked at the Kenwood TK-481's but the radio's internal IF filters kill the signal once you drop below the upper band limit. To make them really functional they need to be replaced. Second, you need a utility to put in the real frequencies since the FCC requires the use of channel numbers I believe. Not convenient for Ham use. https://www.qsl.net/kb9mwr/projects/900mhz/plan.html I noticed there is a code plug hack to modify the XPR6550 800 MHz radios. I think I can find those fairly cheap.

Oh, it's the 400 to 470 MHz band split model. Perfect for Ham Radio's 70cm band and also covers the FRS/GMRS channels too when running analog FM.

If you shop carefully you can find some good deals. I got this one eBay for $110 on an auction I won, it's a TK-5320. https://comms.kenwood.com/common/pdf/download/TK-5220_5320_Specsheet.pdf The radio looked like new, didn't have a scratch on it anywhere, not even a finger print on the display cover. I had to get a power brick to go with the charger base and the radio came with a used 3300mAh Li-Ion battery pack.

My buddy didn’t program the radio. He purchased it from another Ham who had gotten it from a guy that worked for the FBI, I believe he said, tonight at our weekly coffee meet. I’ve seen a person selling a service doing exactly what you mentioned, hacking the code plug, in this case to drop the lower limit to 440 from the normal 450. I’ve hacked some Kenwood code plugs, the ones I played with used simple XOR encryption, to see what they really contain. The idea was to hack a code plug for one of the cheap ProTalk radios, the ones where you can only select frequencies from a predefined list, to enter some GMRS channels. I don’t have one so I sort of dropped the idea for now.

Check it out. https://www.ebay.com/itm/Motorola-XPR6550-Mototrbo-Digital-Two-Way-Walkie-Talkie-UHF-Portable-Radio-/174821776460?mkcid=16&mkevt=1&_trksid=p2349624.m2548.l6249&mkrid=711-127632-2357-0

If you can find the FCC ID look it up and see what certifications it has, likely just Part 90.

The version I found on-line has some modified DLL files to enable the Canada full frequency range for programming anything above 866MHz for radios in that part of the UHF band, enabling the 25/20 KHz bandwidth and by-passing any code plug passwords that might be set. The password thing looks like it works because I downloaded a sample template. Using the RM app, I think I tried, to edit the template it wanted a password. I followed the patch instruction to type in anything and it will work, which it did. After playing with the Radio Manager app I have to agree it's NOT for working with just a few radios, but a rather large fleet. I had it installed so might as well play with it. Looks like I can just ignore it now. The Motorola stuff works different than any of the other CPS systems for my other radios. I do have the D878UV and built a code plug from scratch with both analog and DMR channels. That got me somewhat familiar with DMR concepts. Looks like most of that applies to the Motorola radios. Just have to sort out whatever the differences are in the terminology. At least the help files aren't too bad. I'll be talking to my buddy about buying his XPR6550 if he doesn't want way to much for it. Some of the used ones on eBay look pretty good price wise, at least not crazy expensive. One thing I quickly found out using the Motorola CPS, when they say the frequency range for a given model is 403 to 470, they mean it. You can't enter anything outside of that range. Kenwood radios are not like that. They will let you enter in an out of range frequency but you have to click through a warning message each time you do it. Looking at used XPR6550's on eBay I'm checking the FCC ID numbers to make sure exactly whats being sold. One seller has a radio up for sale, but all the ID stickers are very obviously missing. You figure out what that means.

I'm with you on that account.

For GMRS all you really need is a 1/4 wave antenna. That's about 6 inches long. The multi-band antenna won't do you much good unless you have a multi-band radio. The antenna is physically longer because it's likely designed to work on the VHF band where the frequency is lower and thus you need a longer antenna to be resonate. Stay away from the ultra short ones too, those seems to be around 3 to 4 inches long, and will defiantly be inferior to the normal 1/4 wave design. If you're the kind of person who likes to sit the radio upright on a table to monitor the longer antenna makes the radio more prone to falling over. Be vary careful buying cheap antenna off sites like Amazon, eBay etc. They are full of counterfeit antennas with packaging that looks almost identical to the real deal. Nagoya antennas seem to be one of the favorite ones that get counterfeited.

Best thing is look in the service manual. If its possible the manual will explain how its done. Looking briefly it appears the answer is no to your question. http://manuals.repeater-builder.com/Kenwood/tk/TK-8360/TK-8360(H)(K2_M2)_B51-8964-00.pdf As a matter of practice I spend time hunting down all the relevant documentation, in PDF format, for any radios I have or plan on buying. I have a library of folders for each radio/model series with user guides, service manuals, notes, FCC grants, modifications if any and manufactures brochures. The last one is the first thing I look for when thinking about purchasing a used radio. Excellent source for features, exact frequency ranges, on UHF it's common to have more that one, number of memory channels etc. If I don't like what I see then I've saved myself some money by not getting something I won't like or can't use. https://pdfs.kenwoodproducts.com/30/TK-7360HV-8360HUBrochure.pdf http://manual.kenwood.com/files/53d7482397066.pdf https://fccid.io/K44415502

I'm thinking about maybe adding some Motorola radios to my collection. Looking to buy a buddy's UHF XPR6550, and later adding in the VHF version. Before doing so I want to be sure I can even program Motorola radios, otherwise they'll just be expensive paper weights. I located and installed Mototrbo CPS V16 build 828, with the wide band (25/20 KHz) and full Canadian frequency hack. It seems to work but is considerably different than any other radio programming software I've used. My question is there any good written training materials for download showing how to use it? The actual code plug editor I'm sort of figuring out, playing with one of the sample code plugs, but creating radio "templates" using the Radio Manager app I'm getting nowhere with it. I added what I think are some radios but I can't seem to locate or add in the so-called templates. The software looks like the aim is for fleet management of radios. Maybe it's just not what I should be worrying about.

Business band type radios like the Kenwood's do not use offsets. If you look at the radio programming software there are two entries for frequencies. One is strictly used for receiving and the other is just for transmitting. For example you want to use a repeater the receive frequency would be 462.675 and the transmit frequency is 467.675. There are two tones which you can use, separately, also for receiving and transmitting. The transmit tone is the "ENC" while the receive tone is "DEC". You don't have to use a receive tone. I never use them, just the transmit tone. That way I don't care what tone the repeater transmits, I'll still hear it.

That's actually is very well made! VHF and UHF antennas are fun to build since they are rather small for the simpler designs. If you look around on the Internet you can find scanned PDF's of antenna design books. I'm not talking about the crazy vector calculus filled pages using Maxwell's equations either. They are basically construction projects that anybody with modest skills and tools can build. This is just a sample of what you can on the Internet with some effort looking. http://hamradio.uz/media/uploads/2018/04/19/arrl_antenna_book_21st_ed.pdf