Lscott

Can you provide a definitive reference for the above comment?

You might getaway with slipping the payments past, but where are you hiding the "new" radio?

They can use the phone on board. https://weather.com/news/news/2019-01-07-astronaut-accidentally-dials-911-space-station https://youtu.be/3L82DHQfcF8

My radios were aways sent back to a manufacturer approved repair depot. They would have all the required test gear to work on the class of radios they have been approved to service. For scopes I would just buy one of the “cheap” digital Chinese ones new. Our company purchased a bunch of dual trace 50MHz ones from Rigol. They held up well considering how our service people beat their equipment up in the field.

Gets to be an addiction of sorts.

I've purchase many used radios on ebay. If you shop carefully you can find some good deals. Just make sure the seller has a return option. I did buy a few radios with no return option, however many sellers are HIGHLY motivated to avoid any negative feedback. In the few cases I got a bum radio, with a no return policy, the seller refunded the full, or nearly so anyway, the purchase price and told me me keep the defective radio. In that case I ended up sending it out for repair, which basically cost about the original purchase price. So, in the end I spent about the same amount of money, but ended up with a fully checked out, repaired and aligned radio.

One of the first commercial radios I purchased was a Kenwood TK-270G. It works fine on MURS. It's not Part 95 certified for it since the radio was certified in 1999, before the MURS service was created. My understating is it should be fine to use, grandfathered in, so long as the power, frequency and bandwidth are set correctly for the 5 channels. https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-95/subpart-J/section-95.2705 https://fccid.io/ALH29463110 https://www.manasrekha.com/pdf/TK-270G-370G.pdf

My experience with Kenwood radios is it’s possible to operate the radio outside of its official band split a bit. With the lower official limit of 146 it’s likely you can get it down to 144. I’ve had better luck with the 40 MHz range in the band split than the 70 MHz or higher ones. Where possible I try to get the 400-470 split on UHF. That covers the Ham 70cm band, GMRS and the usual commercial frequencies. This range seems to be more common on the dual FM/digital mode radios. It’s much harder to find in the analog only models On VHF I love my analog only TK-2170’s, those are 136-174 split. Perfect for Ham 2M, MURS, marine, FM railroads and NOAA weather. These are the VHF version of the TH-3170 I typically use for Ham 70cm repeaters and GMRS.

Yes. Then it comes in two frequency splits to make it more interesting. https://two-way.ca/wp-content/uploads/2019/11/TK780-specs.pdf If the goal was to get a 2M radio for ham it might be ok with the right spilt, 136-162, otherwise the seller is the one who got the steal on the deal. I always get the manufacturer’s brochure for any radio I’m interested in to double check the specifications first. A few that looked good initially I just forgot about it once I saw the specifications. The second thing is look up the FCC ID to see what the frequency range is. You can look up the official frequency range on the FCC’s database with the ID. Most sellers show the tags on the radio. If they don’t ask for a photo. A lot of sellers get the description all wrong. If they don’t have the ID’s or photo then forget it. There are some dishonest sellers out there trying to dump basically worthless radios for high prices.

Does anybody know of any use of dPMR, not to be confused with DMR? As a note dPMR has the same on-air modulation as NXDN, but the digital protocol is totally different. There is a “license free version” dDPMR446, but that’s a European thing. I’m looking at the licensed version of dPMR. https://dpmrassociation.org/dPMR-a-brief-overview.html I have some radios with this mode and haven’t found any info on line about Ham activity using it. https://forums.mygmrs.com/gallery/image/500-ic-f3162dt-front-and-back-sidepng/ It doesn’t even appear as a “special” mode to search for even on “RepeaterBook.com” thus my question.

I have the software for the MTX400. Never tried it since I don't own any Midland radios. MXT400_Setup_1.05.zip

Unfortunately manufactures "assume" that GMRS repeaters are using the "usual" 5MHz so that gets baked in to the radio's programming software and or firmware. For the most part it works so it's a fair assumption and simplifies the radio programming. This seems to be the case with the GMRS specific radios being sold. The options to work around that is to to use a radio that can be unlocked so arbitrary frequency splits can be programmed, or use a commercial grade radio. The later option typical requires the radio tech to program in two frequencies, a receive and a transmit, there is no entry for a frequency split, or offset. When I first got into using commercial grade radios years back, and coming from a Ham radio back ground where the radios had entries for the offset, it was a bit of a mental adjustment to get use to the idea. You do have to pay attention to which frequency goes into which column. It's easy to switch the two around and end up transmitting on the output frequency and receiving on the input frequency, oops. This is one of my preferred analog only radios for GMRS. https://forums.mygmrs.com/gallery/image/263-tk-3170jpg/?context=new This is a sample of the programming for a Kenwood TK-3170, which is what I usually carry around for Ham UHF and GMRS use.

You might want to look at something like the antennas in the below link. https://n9taxlabs.com/shop/ols/products/dual-band-murs-gmrs-slim-jim-with-10-or-16-foot-cable No ground plane required. You can try hanging it up on the window.

Oh, that won't be very popular.

Gee, that's might be hard to do. Have two radios and a cold beverage, but only two hands. Got to make a hard choice what to hold on too.

The interesting thing about the rules is it simply states that the repeater input frequencies and output frequencies have to be picked from the allowed list. Note the rules say nothing about any kind of required frequency shift. https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-95/subpart-E/section-95.1763 There is no requirements the input and output frequencies must be 5MHz apart. While that is the usual case it's not required. One could really frustrate users of preprogrammed, firmware locked, GMRS radios by selecting a pair of frequencies, from the allowed list for repeaters, that are not using a 5MHz split. Any talk about how that would affect channel sharing is another topic.

Yes, but I read it as only allowed as specifically mentioned in the rules under narrowly defined conditions. I also though I read amateurs are only allowed to communicate with other stations in the amateur service, USA or other countries, as a general rule at one time, but I can't seem to find the exact location where that was in Part 97. I could be miss remembering.

Great! I had picked up a BTECH amp used at a Ham swap for about $50. It was basically new in the box. https://baofengtech.com/product/amp-u25d/ I noticed the power gain drops off outside of the Ham band noticeably from the max of 40 watts. On the GMRS repeater frequencies for 4 watts input I get maybe 20 to 25 watts out. It could be better, but I didn't pay that much for it. I was more interested in something that would handle all of the typical digital modes and FM analog for the various HT's I own. The amp fit the requirements. I've been looking out for a deal on a used VHF version of the amp.

I've seen those for sale. I always wondered if they were any good.

What kind of amp are you using BTW?

These are the Part 97 rules that apply. 97.111 Authorized transmissions. https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-97/subpart-B/section-97.111 97.113 - Prohibited transmissions. https://www.law.cornell.edu/cfr/text/47/97.113 97.115 - Third party communications. https://www.law.cornell.edu/cfr/text/47/97.115

Very nicely built!

https://wd8iel.com/wp-content/uploads/2023/01/Duplexer-Cable-Length-Determination-Procedure.pdf https://www.repeater-builder.com/antenna/w6nbc-duplexer-book/ch9.html

Velocity factor typically unimportant unless you're using line sections for building filter stubs or phased array antenna systems. What the number specifies is how fast the signal propagates along the coax verses in free space, which at a velocity factor of 100 percent would be exactly the speed of light, so at 85 percent the signal is moving at 85 percent the speed of light. https://picwire.com/Resources/Technical/Technical-Articles/Velocity https://www.febo.com/reference/cable_data.html The reason why it's important for phased array antenna systems is the length of the cable has to be calculated so the RF signal arrived at the respective antennas at the exact point in time for the radiated RF waves to add/subtract in space to give the desired signal strength in the preferred direction. https://hamsignal.com/blog/2-element-vertical-phased-array-my-first-attempt

At a press conference on August 12th, 1986, US President Ronald Reagan said, “The nine most terrifying words in the English language are ‘I’m from the government and I’m here to help.’”