Lscott

Yes, it is a lot to digest. The first chapter is likely all most people need to read. The bottom line is worrying about the different between an SWR of 1:1 verses 1.5:1 isn't worth the trouble.

From the looks of things I would say they are serious. However I'm shocked these people will bet their life on a cheap $25 Chinese radio. It's not like they went around begging for free radio handouts. From the money they spent on the weapons etc. they certainly can afford better quality radio gear. At least get something with good encryption, like AES256, if they're worried about the government spying on them. A cheap UV-5R isn't it.

Like these guys? https://radiofreeq.wordpress.com/2016/01/19/militia-radio-frequencies/

That's discussed in the book at the following link. http://www.w3pga.org/Antenna Books/Reflections III.pdf

That's cool. Looks like you're primarily a Motorola guy. I have a few XPR-6550's and XPR-6580 (CPS hacked to put it on 33cm band). You check my album out you can see my collection.

Which radios and models? I'm mainly a Kenwood guy myself.

Well at least we know where the Chinese are earning their bribe money.

Wow and that even rimes! ?

I typically saw the orange or yellow plastic ones. You mean like this one?

Yeah, the infield was a mess. Looks like they ripped up the asphalt they put down the prior year but left chunks of it, pebble sized to fist sized, all over the place in the walkways. Made walking a bit tricky and if you had a wheelchair it was a poor experience.

The weather was great. A bit warm on Friday and sunny. Saturday it rained a bit early in the morning. By 10 AM everything was dry, NO MUD, partly sunny and it cooled off to the low to mid 70's. Looked like a really good turnout.

Kenwood offers a dPMR446 license free radio that complies with the legal standard for that service. https://www.walkies.nl/downloads/kenwood-tk-3701d-brochure.pdf However I'm interested in a higher power dPMR radio. Kenwood, I think it's been discontinued, had a version of their NX-220/320 radio that could be firmware modified to switch from NXDN to dPMR. The link is for the "E" market code radio. https://www.kenwood.eu/files/file/comms/uk/brochures/nx/NX-220E-320E_Brochure_with_MPT.pdf I have one of the NX-320K, US market code radios. I might be able to force switch the market code using the "engineer" version of the programming software. However so far I've had zero luck finding the firmware.

I would assume so since it is used for commercial radio application. The link below is the main site for dPMR. https://dpmrassociation.org/ The standards documents are found here. https://dpmrassociation.org/dpmr-downloads-technical.html Looking at "Repeaterbook.com" they don't have a selection for dPMR so it's not possible to do a quick search for dPMR enabled repeaters. For example looking at the UK, I might be making a business trip there in the near furture. https://www.repeaterbook.com/row_repeaters/index.php?state_id=GB I was interested in the mode due to the possible trip. They have a license free service there called PMR446. https://en.wikipedia.org/wiki/PMR446 The analog FM looks very much like our old rules for FRS but uses a different frequency range. Remember in the UK the Ham 70cm band is only 430 to 440 MHz. Which prompted me to as some time back if anyone notice European visitors using their PMR446 radios here on the Ham band. It would likely be at major tourist locations like Disney Land. There also two digital voice modes approved for their license free service, DMR and dPMR. https://kenwoodcommunications.co.uk/files/file/comms/uk/pmr446/PMR446-White-Paper-V6_18AUG2016_JT_KB.pdf Since I don't have a dPMR radio I'm looking at taking one of my Kenwood DMR radios and programming it up for FM and DMR on their PMR446 frequencies. https://forums.mygmrs.com/gallery/image/290-nx-1300duk5/?context=new https://forums.mygmrs.com/gallery/image/255-tk-d300e-fmdmr/?context=new Oh, they have the same issue there too with people running non approved radios and power. Their radio commission, like the FCC here, seems to ignore it. There is a message board like this one but mainly for the UK. You can get an idea on what goes on there by reading through some of the threads. https://www.transmission1.net/

The field should be minimal under the radials. And as I mentioned I ran only 1 watt using DMR. Since DMR uses two time slots and on simplex only one is used thus the average power is around 0.5 watts. Next consider one is holding an HT a few inches away from the face with an output power of 4 to 5 watts at about the same frequency on GMRS. So, which one is really worse for RF exposure?

It should be legal to use on the Ham bands here. It’s an open standard that’s published so nothing is secret about it. I would imagine it’s also legal for Part 90. It’s a FDMA modulation emission, just like NXDN which is already used here, but the frequency shifts are a bit different and the digital protocol is too. The bandwidth is the same as the very narrow NXDN mode and fits into the same 6.25KHz channel allocation. The occupied bandwidth of both is only 4KHz.

If you do what others tried, mounted HT antenna on a hard hat, the match sucks, no ground plane. I guess the Tin Foil would fix that. ?

Well this got a lot of comments from people and photos taken at the Hamvention last May. The match was about 1.1:1 or so at our group frequency of 448.5MHz. It’s a 1/4 wave design. Ran DMR at 1 watt so the average power was about 0.5 watts.

It’s a dual band radio. Using the right passcode in the programming software allows changing the band limit configuration to cover the required frequency range. The important question is it legal to use the radio to transmit on those services. Without qualification the answer is no. Anybody who does should understand this fact. After that it’s up to them what they choose to do. It’s not my job to play the part of a radio cop. About dPMR you can find info on the Internet. As far as I know there is nothing that prohibits its use here. When digging around for information on it I haven’t found a definitive reason why it’s not used in the US at least. My guess it’s just a marketing issue and more importantly which CODEC is used. The dPMR standard has THREE different and incompatible CODECS specified with an optional vendor specific one allowed. Whereas DMR, NXDN and P25 all use a specific one, AMBE+2, regardless of manufacturer. This ensures radios using the same protocol can inter communicate between manufacturers using compliant radios. That wouldn’t be true for dPMR radios. dPMR MoU tech lib Voc Bits V1 (2019).pdf

My D878 doesn’t have a problem with it either. Myself I’ve been looking for a couple of radios that can do dPMR, which is used mainly in the EU. I haven’t seen it in North America so far. It’s very similar to NXDN but the protocol is different. Anyway at least you didn’t get stuck with one of those crapy old Baofeng DMR radios.

You might want to check yours. https://radiosification.blogspot.com/2016/12/dmr-radios-to-avoid.html

Mine says “DEA” on the back. For some reason people stay away from me at concerts.

I have a load of radios. Hasn't help me any. ?