Lscott

FCC database search for the Virgin Islands shows only 15 active licensed GMRS users. I didn’t drill down to see who was located where however. If they are spread out over multiple islands your chance of contacting one on the air likely isn’t very high. The chance of contacting someone using a cheap FRS radio, simplex only since they don’t have repeater functions, might be higher. I would also suggest you look at getting at least your Ham Tech class license. That will increase the opportunity of contacting somebody during an emergency. About a third of the group of GMRS users on my local repeater are also licensed Hams.

If you're worried about having communications after a major storm you should also think about a source of emergency power. Last storm through Puerto Rico for example the power was out for a really long time from the reports on the news. After a few days you likely won't find any gas for a generator so a long term solution is needed. You will likely want something like a small solar panel, charge controller and battery. Then look for a 12VDC battery pack eliminator for the radio. I have a few charging cradles for the commercial Kenwood radios, with one modified to use 12 to 14 VDC input, instead of wall outlet power, to recharge the battery pack. If you can't find a 12VDC battery pack eliminator then a few spare battery packs you can cycle through the charger works too.

If GMRS ever allows DMR I would think SFR mode would be the way to go since it would be simple for a user to setup, no fancy controller or cavity filters to deal with. In fact this would be ideal for a Ham buddy that's into off-roading with his Jeep and the group he belongs to. They are switching to GMRS since that seems to be the direction the off-roading community is moving towards. He's trying to get the group members to get their Ham Tech class tickets. If he can do that then using DMR with one radio setup as the repeater using SFR mode would fit exactly what they are looking for without a complex system to drag around. If a particular frequency is busy you just switch to another one. Can't do that in the field with a conventional setup.

DCDM, allows two voice channels on the same frequency. That's good to know. I wasn't aware there are radios that could coordinate the time slot sharing without a repeater in the mix. The question there is how many DMR radios have that capacity? The point about single frequency repeaters using DMR I think is a significant development. It just so happens the CCR's I linked to offer it but I'm not advocating people buy those CCR's, just used them as an example.

I believe that is only true when operating through a DMR repeater. The repeater supplies the sync signal so each radio knows when to transmit based on the time slot selected. When operating simplex there is no sync signal to determine which of the two times slots is slot 1 or slot 2. One of the interesting aspects of DMR is with the right programming of the firmware a radio could supply the sync signal. In the case of the D578UV, from what I've read, can do this thus you can run a single frequency repeater, no offset or tuned cavity filters required. There are some other DMR radios that claim to have the feature as well. https://www.ailunce.com/blog/What%27s-Single-frequency-repeater-function https://www.rexontec.com.tw/en/product/RPT-810.html

You can try the antennas from Ed Fong. He sells several models from base antennas to "roll-up" types for portable use. None require a ground plane so they are ideal for temporary use. For a base type antenna look at this one. "DBJ-1 (commercial) dual band base antenna - (152-157 MHz and 460-470 MHz). Maximum power input 75 watts. - $36" For portable use< roll-up type, this should work. DBJ-2 (commercial) dual band roll up antenna kit - (152-157 MHz and 460-470 MHz). Includes adapters for BNC, SMA and SMA - female. Also includes a 6 ft extension cable. Maximum power input 50 watts. - $36 The link to the website is below. https://edsantennas.weebly.com/ These are "J-Pole" antennas. For some background on what they are a basic theory how they work can be found at the following link. https://en.wikipedia.org/wiki/J-pole_antenna Without seeing your situation a roll-up antenna might be a good choice if you have something nearby to throw a light string or rope over, like a tree limb. Then you just hoist the antenna up by the string, the higher the better. When you're done just drop it down and store it. Likely you can get away with leaving the string in place for next time. Some years back when I lived in a ground floor apartment I used a portable light fiberglass "pushup mast" stuck in a heavy duty speaker tripod. That got a telescoping dual band antenna up about 20 feet. I ran the coax out of the window. This was done at night so as not to attract too much attention. http://www.randl.com/shop/catalog/index.php?manufacturers_id=67&sort=3a&page=20&osCsid=6bcm5d1bpm8b0ar83lvi2h2a40

As mentioned you can use VirtualBox to make a virtual machine and run Windows in it. You can get an old version of windows here. Using Windows XP usually isn't required so running Windows 2000 should work fine. https://winworldpc.com/product/windows-nt-2000/final

For Kenwood handheld radios I would also recommend the TK-370G-1 and the TK-3170. Both are part 95 certified. https://mra-raycom.com/wp-content/uploads/simple-file-list/Specifications/portables/TK-270G-370G-Product-Brochure.pdf https://5.imimg.com/data5/MT/AL/MY-2136226/tk-3170-handheld-portable-walkie-talkie.pdf Make sure you get the type 1 radios. For UHF there are 2 or more models available. You want the one that includes 462 to 467 MHz in its operational ranges.

Have a look at this site for mobile wiring recommendations. While the topic is mobile Ham gear the same exact recommendations apply for GMRS radios. http://www.k0bg.com/wiring.html

I posted a link to this in another thread about the same exact topic. http://www.repeater-builder.com/k7pp/art005.html I think the best advise given is to stay away from the guy, do not confront him. You have no idea to what length he will go to if confronted. If he is asking for personal info from kids this would likely be of interest to the local police. The guy is maybe a known offender so the matter is better left to the local PD. They do keep close watch on these people.

Well just an update. TYT won't supply a schematic but they did send me two new pin jacks free of charge. Granted CCR's are not the greatest radios but for a general "beater radio" its not bad. I'm not expecting great performance out of it. If I have real critical performance requirements I'll depend on my Kenwood radios. People forget that years ago electronics made in Japan were considered a joke too. Now those same Japanese companies have upped their game producing quality products and are respected manufactures today. I wouldn't count out the Chinese where down the road they end up producing top quality products at some point.

Well there are really two issues here. One is cheap labor. Second is cheap design. You can still move manufacturing back to the US and still produce garbage because the design was cheap. The CCR's are the way they are because of both of the above factors. Cheap labor keeps cost down. A cheap design that takes maximum advantage of highly integrated chips which very often results in a compromise somewhere in performance with a trade off in reduced cost. Now you have a really cheap radio with so-so performance. There is a reason why the higher end radios perform better, cost more, than many CCR's is because more effort was made during the design and testing phase with less corners in performance cut. To design high performance hardware requires very careful evaluation of nearly every component used. For a $25 Baofeng just how much R and D money do you think they are going to spend on such a cheap radio? For the CCR's they use a "datasheet" reference design, tweak it a bit. Then try some "can you hear me now tests" and then it goes to marketing.

Just for my info what FCC rules are they violating?

I think the closest thing to what you're asking is a "simplex node" connected to the linked GMRS repeater network. For an example have a look here. It looks like a modified Baofeng BF-888S UHF radio was used. These radios go for $15 or less on-line. https://gmrs1.yolasite.com/

Yes. Look on page 11 of the service manual for how it's done for the TK-370G models with full keypads. A hardware mode needs to be done in addition to enabling self programming in the software. http://www.repeater-builder.com/kenwood/pdfs/tk-360g-tk-370g-svc-man.pdf For the older TK-370 32 channel model the instructions are here. http://rsws.zapto.org/radiosoftware/kenwood/Tk270.pdf After looking at how it's done for the 370G I would rather use the software. Trying to do this in the field would be "interesting" to say the least.

I still have my very first radio, a Kenwood TH-G71A dual band, I purchased new. Had some repairs done on it over the years but still in great shape and working. Only draw back is it can't do narrow band.

I can speak to the few Kenwood portables I own. Those are: TK-370G-1 (FCC ID ALH29473110), 128 channel, wide/narrow band setting per channel TK-3170-1 (FCC ID ALH34713110), 128 channel, wide/narrow band setting per channel TK-3140-1 (FCC ID ALH32263110), 250 channel, wide/narrow band setting per channel TK-370-1 (FCC ID ALHTK-370-1), 32 channel, wide band only TK-3160 (FCC ID ALH36423110), 16 channel, wide/narrow band setting per channel TK-3360 (FCC ID ALH415100), 16 channel, wide/narrow band setting per channel Pro's: All of the above are Part 90 certified, however the 370G, 3170, 3140 and the 370 are also Part 95 certified thus are perfectly legal to use for GMRS. The 370G and 370 are larger older models, built like a tank and a bit on the heavy side. All the other radios are "palm-sized". Depending on the radio they will take either a nickle metal hydride or lithium ion battery pack. Some will take either one. The battery packs and chargers seem easy to find, original or clone on line. All of the radios, except the 3140, use the standard Kenwood style two pin accessories and use the cheap "Baofeng", cheap Chinese, programming cable. The 3140 however uses the Motorola type multi-pin adapter for accessories and programming cable. I've had good luck finding the programming software with license keys on line. Some have the "engineer's" key which lets you do anything with the radio even if it's password locked. If one wants to use the radios for the Ham 70cm band some model sdo cover 440 MHz and up, or allows entry of frequencies below the lower official band limit, 450 MHz, with a warning popup. The radios will operate there. From what I've read the Kenwood radios seem to work about 5 percent outside of the official band limits so for a lower limit of 450 MHz you likely can get the radio to work down to 440 MHz. I've got mine programed that way, and the simplex along with the repeater section are primarily above 440 MHz anyway. I've had good luck finding operator and service manuals for these radios as well. Con's: The radios are typically only 4 watts max output, option to select low of 1 watt. The difference between 5 watts and 4 watts I doubt is noticeable in practice. Chrip doesn't fully support these radios, and with most of them it's very buggy. I highly recommend using the official Kenwood software. They all use, except the 370, the reverse SMA antenna connector you find on just about every cheap Chinese radio. I think, my guess, is when they designed the CCR's they simply copied an existing interface design, looks like they picked Kenwood. The 370's antenna connector however uses the old Motorola screw stud type antenna connector. No true VFO. However on a few of the radios, after removing a configuration diode and enabling the feature in the programming software, the radio can be front panel programmed, but only to a memory slot. I know the -370G is possible since it's covered in the service manual, not sure about the others. Most of the radios do offer some form of security, voice scrambling or inversion, but legally it can't be used, at least not on the Ham or GMRS services. For Part 90 service I don't think that's a problem.

That may not be as big a negative as you would think. Looking at the ARRL band plan for the 70cm band the simplex section isn't that big. So, on some of my Kenwood radios I programed in a series of simplex frequencies like 446.000, 446.025, 446.050 etc. You can look at your area to see what they typical channel spacing is. The memory names were 446-000, 446-025, 446-050 etc. Now when I rotate the channel selector it sort of looks like a VFO. Not perfect but does a good job. The radios I have use "zones" so the "VFO" channels were assigned to its own zone for convenience. Other zones were assigned the GMRS channels, repeaters etc. That kept everything organized. Then I programmed one of the function keys to switch zones. Even with a 128 channel radio I was able to cover most of the simplex sections with a few repeaters and the GMRS channels too. If you can find a radio with 250 or more channels you likely can cover everything with spare memory channels for future use.

Well I'll find out with TYT. I have one of their cheap radios when I'm not particular about the performance. This one the internal microphone quit working, external speaker mic works fine. I suspect its a problem with the jack or a cracked solder connection on the circuit board. Either way I sent their tech support an email asking for a schematic and or service manual for it. I'll see if I really get one. As a side note all of my Ham and commercial Kenwood radios I have the service manuals for them EXCEPT for the newest model, TH-D74A. All the other ones were easy to find and download online. https://www.mods.dk/manual.php

As you pointed out many sellers have little to no clue, wrong description, wrong model, wrong band split etc. for the radio they are selling. As a buyer one should do the research and know something about the brand and model of radio before bidding or buying one used.FWIW sellers with little clue about what they are selling is where I have got the best deals verses sellers that are in the radio business who do know, and they typically charge too much in my opinion in many cases. The two things I do is look for a photo showing the manufacture's model number on the ID tag, normally on the back of the radio someplace, and the FCC certification number. From that I can research that model for the brochures, user manuals and service manuals. The FCC certification number leads to the FCC grant info where i can see just what bandwidth, band split and power the radio was tested at and certified. After that I'll also look to see if the programming software is "obtainable" and any required cables or interface box can be procured, same with battery packs for portable units and chargers. For some portable units I have checked for availability of cheap aftermarket case rebuild kits. Some of the used radios the electronics are likely fine but the case is in very poor condition or simply broken. If I can get a radio that is fully functional cheap and a case rebuild kit for 10 to 15 bucks I end up with a very nice radio for an overall good deal.

Looks like it's about the same thing as the Kenwood TK-3360's. They even look similar. Kenwood's TK-2360/3360 https://www.kenwood.com/usa/Support/pdf/TK-2360_3360.pdf Motorola's CP200 base model https://bearcom.com/media/catalog/product/files/cp200xls.pdf

The point about using CCR’s as an entry to the radio hobby, because it’s low cost, until one figures out if they really like it or not is valid. However the flip side of the coin has to do with real world performance. Most of the CCR’s perform poorly in the receiver section, low sensitivity, susceptible to overloading, poor selectively etc. A newbie, with no prior two way radio experience, their poor perception of radio communications is due to the budget priced radios poor performance and not really a representative example. That alone may convince them it’s not worth continuing down the road all because of a poor choice of equipment to start out with, and they don’t even know it.

No. The J-Pole antenna is a 1/2 wave length long for the radiating section. The end of the antenna has a rather high impedance making for a very poor match to 50 ohm coax. Thus the extra length is due to an additional 1/4 wave matching section, the section with the short length of extra conductor parallel to the long one, where the tap point selected yields the desired 50 ohms. The overall length will be closer to 3/4 wave length long. At 462MHz the wave length is about 64.7 cm (25.8 inches) and 3/4's of that would be 19.1 inches, just what you measured. http://www.ka3pmw.com/files/jpole_presentation_rev2.pdf

Good point. If Wouxun is not supporting their vendors then as a user what kind of support will one see from the vendor with warranty issues? It would be easy to say send it back to China because we can't support it anymore. As a customer with a problem radio does one want to get stuck in the middle of a dispute between the manufacture and their local sales/service rep's? Anyway it's another data point to consider when making a purchasing decision.

Somebody is not having a good experience with Wouxun radios. http://www.wouxun.us/index.php