Lscott

I have no idea. It's a free download and simple to install. You can get it and check.

You're likely to do well going with a commercial grade radio. They are designed to withstand hard use and function in harsh RF environments. There are a lot of quality used ones on the market. The programming can be a bit more involved but you also gain flexibility that many of the cheaper Chinese radios lack. Some of them have Part 95 certification, required for GMRS, in addition to Part 90 so there is no issue with questions about the legality of using them on GMRS.

Use the attached file as a guide. https://www.polyphaser.com/search?Category=RF+Surge+Protectors&Rfpssp99app=Amateur+Radio&sort=y&view_type=grid https://www.polyphaser.com/search?Category=Grounding&sort=y&view_type=grid Antenna System Bonding and Grounding Requirements in the USA.pdf

Just so people have an idea what these antennas look like and the performance I attached a datasheet for the DB408. For repeaters there is one spec that often gets overlooked, that's the "down tilt" angle if it has one. That's important at high gains and you need close in coverage to the site. https://www.kpperformance.com/Antenna-Downtilt-A-Practical-Overview.html https://www.telecomhall.net/t/what-is-antenna-electrical-and-mechanical-tilt-and-how-to-use-it/6388 DB408-B Product specifications.pdf

Some have recommended carrying a SAT phone.

As a side note if you have to deal with industrial equipment water, even water vapor, has corroded electronic components. This was particularly true of leaded types, not SMD. The leads are cheap steel wire which are copper plated. Crack or otherwise break the copper plating then the steel wire underneath starts corroding. I've seen enough PCB's where the parts have fallen off due to this.

http://www.wouxun.us/category.php?category_id=94

https://groups.io/g/AT-D578UV/topics

Well if it gets crowded enough maybe the FCC will expand the number of frequencies allowed. They eventually did that with CB, went from 23 channels to the now 40. In Australia, and some other areas, have a UHF FM CB service with 80 channels. It seems to work for them. https://en.wikipedia.org/wiki/UHF_CB Example radio. https://www.ohmelectronics.com.au/products/ic-450

Well at least on GMRS you don't have to deal with the idiots on the "Super Bowl", CH6, on 11M running multi KW stations with their echo mics trying to own the airwaves.

That's always an excellent practice! Due to the large number of models of HT's I own, or just wanted to mess with the programming software, I have to be VERY organized in the way I save and track the code plug files. I use a separate folder for each model type. In each folder if there is more than one sub type or band split I have a folder for it. I also save any original code plugs from the used radios I buy as well. I've attached some screen shots of how I do it. Note the code plugs are all tagged with a date code: xxxxyyzz, xxxx - year, yy - month, zz - day. Saving old code plugs sometimes helps if I'm making a major editing change and screw something up. At least I have the older version to fall back to.

Reminds me of the old “Liberty Net” that got lots of attention.

Maybe the batteries were dead and he didn't notice.?

Around the Detroit area 2M and 70cm are dead most of the time. Many of the repeaters see little use. On 70cm with 20MHz of spectrum it’s easy to get lost in it if you’re looking to talk to somebody. On GMRS you only have a handful of frequencies to use so it doesn’t take much to find activity. On the Ham 70cm band yeah you have some grumpy people. With GMRS it’s geared for “family” use and the range of permissible uses is far greater than the Ham band allows. On GMRS everyone has the same type of license call, none of the 1x2, 1x3 etc. calls depending your license class. Some Hams won’t talk to somebody with a tech class call for example. On GMRS nobody cares how much DX you’ve worked, how fast you can send and receive CW, you run 1500 watts into an antenna on a 200 foot tower in your yard etc., it levels the field.

That's the interesting thing I noticed too with the FCC grants. Part of the documentation for each radio model I own is get the FCC grant info, which shows the frequency, power, modulation type and rules part the radio is certified under. Where some of the UHF radios that have multiple ranges and have both Part 90 and 95 certifications are the models that DON'T cover the ham bands. For example the NX-300 models I have in my collection. See attached files and look at the FCC ID's in the brochure for the different band splits. NX-300 FCC Grant - 1.pdf NX-300 FCC Grant - 2.pdf NX-200_300.pdf

As a side note I've notice that a surprising number of schools are now using NXDN radios verses analog. They quit using the cheap FRS radios.

Ah, the magic of 3-D printing. We have a 3-D printer in our engineering department. We don't use ordinary plastic thread. Instead, I'm told, it's a more expensive carbon fiber type for extra strength. For things like belt clips you might want to look into that. Also you have to watch out which direction the layers are put down verses the forces applied. Plastic printed parts have failed along the boundaries between layers, they don't bond that well. A few suggestions have been made where people have put the finished part in an oven to get the plastic temperature up where it will bond better at the layer boundaries then let it cool back down.

https://www.miklor.com/COM/UV_Squelch.php

You could build two of those and mount them at 90 degrees to form a turnstile antenna at 6M. That would give you horizontal polarization and a 360 degree compass coverage. Some Notes On Turnstile Antenna Properties - QEX 2002-03.pdf

After seeing the TH-D74's selling for $1,000 and up on eBay in some cases I can believe it. https://www.ebay.com/itm/394386920360?hash=item5bd34ad3a8:g:v2cAAOSwm0pjoSSL&amdata=enc%3AAQAHAAAA4LPOYFxcbXMope3RzgBYPvEsMI8ZHIf8nhH6%2FeDmniW%2F1xIXD14qQW0B%2F4pMriRSYaTbFGxqYCiHcdn2QpWzqYZVjFbAO9kvot8k0%2FmxeFSqLxeFMYO1J43OJ%2F41lhTO0X4Iedf43yQ54HE1Lp7K8FABrwV%2BdxfkgvnPZ6lArRISC%2FmJ0Zzl2ibsbYpeUFiaFg7ikVdxCS5ra%2FHZXyUGqUS02FfXDeYm10j2JKt%2B7hWdDvvZriDDjvWIKJkbdV53Xzh2DvKinifhwgHPGWlr9McsBhcoJ7WskSgBeusULWBX|tkp%3ABk9SR5DH4PewYQ

For a cheap portable antenna for 6m the one in the link looks simple enough to build out of coax. https://vk1nam.wordpress.com/6m-sota-antenna/

When the band is open most of the activity is on SSB and you may not need a lot of power either. There aren't too many choices in that area. A favorite for portable/backpack operations is the IC-705 which seems a popular choice, put it's not cheap! https://www.icomamerica.com/en/products/amateur/handheld/705/default.aspx https://www.hamradio.com/detail.cfm?pid=H0-017149 HRO will do the MARS/CAP mod for you at extra cost but will also honor the warranty on the radio so it might be worth it.

My TH-D74A HT is modified. These sell for scary high prices used now that they are discontinued.

This doesn't seem to get mentioned much but if you're an active scanner user there might be some pitfalls. https://www.law.cornell.edu/uscode/text/47/605

I'm and engineer, spelling wasn't my strong point.?