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The attached files are also useful. Common Emmision Mode Designators.pdf FCC Service and Station Codes.pdf

I appreciate the kudos! The CB Bar was a great addition. It's hollow square stock with some pre-drilled hole, but it's also easy to use self-tapping sheet metal screws for custom installations. The tubing helped me hide most of the wiring up there.

How about looking at this option?

Nice job! I am big fan of clean installations. How do you like the "CB Bar?" I am going to be moving on from my Midland MXT275 to an Anytone D578, which lacks a detachable faceplate, so I will need to be able to see the radio and interact with it's buttons and knobs. Seems like it might be the cleanest way to mount a radio without a detachable faceplate.

I've got a local Motorola dealer/shop 5 miles from me that also supports the ham radio community and usually has a table setup at any hamfest in the area. Guess I could call him and see if he could check it out. Again, I plan on donating it and don't mind spending another $100 or so to get it up to snuff but if there are issues with it I'll flip it for parts.

We went four-wheeling this weekend, went up to Sedona. On the trail itself the Tidradio TD-5R radios were quite helpful, but we were basically line of sight or not much past it. They were also helpful for the drive up from Phoenix and back down again, we were able to coordinate stops etc. In-town was another matter. I'll have to look up the band-plan or whatever the GMRS equivalent is, there must've been some kind of repeater on one of the channels because occasionally there was a morse-string transmitted, and there was a lot of other random chatter, some of which might have been FRS users. I haven't looked into what it takes to do CTCSS/DCS or equivalent, I will need to do so. Finding a clear channel was a bit of a pain but if we can use those features it might work better, presuming that others are also using those features. I'm now thinking about what I want to do for a mobile install on my truck. In a nutshell I have three services I would need to deal with... receiving commercial broadcast radio (ie, normal FM, possibly ability to receive AM and satellite radio, but the latter is less important to me), communicating on GMRS, and communicating on amateur radio on various bands that Technician allows. I'm toying with leveraging either the factory commercial radio broadcast receive antenna location and using a diplexer, or leveraging the existing hole in the roof of the truck where the satellite radio receiver sits in order to do either GMRS or amateur, or both depending on what I ultimately go with. The shorter wavelength of GMRS may work better with that roof location. This is an Australian D40 Navara antenna: This is what they went with instead of a cowl-mounted antenna like on the Frontier, where instead that hole is used for the satellite radio receiver. If I replace the satellite receiver with a GMRS-tuned antenna and go with a diplexer for the commercial broadcast receiver then this is a pretty good spot for it. Though I haven't decided on if I would like how it looks. I could then decide if the current cowl location gets an antenna that will do some of the ham bands. Or, I could replace the XM antenna with a sharkfin antenna for other Nissans that has AM/FM/XM on it, and then use the cowl position for other purposes, and possibly put a GMRS antenna on the cab further back. We'll see what go with. Been wanting to do something for amateur for a long time, this modern use of communications has given me the impetus to revisit.

They’re all defined in Part 97 of the FCC Regulations: https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-97 (c)The following terms are used in this part to indicate emission types. Refer to § 2.201of the FCC Rules, Emission, modulation and transmission characteristics,for information on emission type designators. (1)CW.International Morse code telegraphy emissions having designators with A, C, H, J or R as the first symbol; 1 as the second symbol; A or B as the third symbol; and emissions J2A and J2B. (2)Data.Telemetry, telecommand and computer communications emissions having (i)designators with A, C, D, F, G, H, J or R as the first symbol, 1 as the second symbol, and D as the third symbol; (ii)emission J2D; and (iii)emissions A1C, F1C, F2C, J2C, and J3C having an occupied bandwidth of 500 Hz or less when transmitted on an amateur service frequency below 30 MHz. Only a digital code of a type specifically authorized in this part may be transmitted. (3)Image.Facsimile and television emissions having designators with A, C, D, F, G, H, J or R as the first symbol; 1, 2 or 3 as the second symbol; C or F as the third symbol; and emissions having B as the first symbol; 7, 8 or 9 as the second symbol; W as the third symbol. (4)MCW.Tone-modulated international Morse code telegraphy emissions having designators with A, C, D, F, G, H or R as the first symbol; 2 as the second symbol; A or B as the third symbol. (5)Phone.Speech and other sound emissions having designators with A, C, D, F, G, H, J or R as the first symbol; 1, 2, 3 or X as the second symbol; E as the third symbol. Also speech emissions having B or F as the first symbol; 7, 8 or 9 as the second symbol; E as the third symbol. MCW for the purpose of performing the station identification procedure, or for providing telegraphy practice interspersed with speech. Incidental tones for the purpose of selective calling or alerting or to control the level of a demodulated signal may also be considered phone. (6)Pulse.Emissions having designators with K, L, M, P, Q, V or W as the first symbol; 0, 1, 2, 3, 7, 8, 9 or X as the second symbol; A, B, C, D, E, F, N, W or X as the third symbol. (7)RTTY.Narrow-band direct-printing telegraphy emissions having designators with A, C, D, F, G, H, J or R as the first symbol; 1 as the second symbol; B as the third symbol; and emission J2B. Only a digital code of a type specifically authorized in this part may be transmitted. (8)SS.Spread spectrum emissions using bandwidth-expansion modulation emissions having designators with A, C, D, F, G, H, J or R as the first symbol; X as the second symbol; X as the third symbol. (9)Test.Emissions containing no information having the designators with N as the third symbol. Test does not include pulse emissions with no information or modulation unless pulse emissions are also authorized in the frequency band.

Here's an interesting tidbit from the California Highway Patrol that "exempts", if you will, radios such as commercial and CB, from hands-free laws. I suspect it applies to ham radio and GMRS as well. You be the judge, I'm just sharing it. AB-1785-CVC-23123-CHP-Memo-Leg-Intent.pdf

This is, i believe, the 4th violation/action the FCC has issued on GMRS/CB radio in the last month - which is more than the last several years combined... I think we are seeing a new dawn in FCC actions in the CB/GMRS world.. 10 years too late, but better late than never.

As a former frequency coordinator, I have to say "depends." Most of the coordination plots use the Longley-Rice algorithm and the predicted coverage area between wide and narrow band remains the same in most cases. Some coverage areas do increase while some decrease, the change being about 3%. As to the performance of a radio at the fringe of the coverage, it again depends on both the radio's specifications and any change to the coverage shift if any,

I'm sure this will spark an argument... but I want to make a few corrections. I'm not trying to pick on you... just want to put a tad more accurate info out there. Like you... my post is not very technical... more of a general concept. You are mistaken about wider signal having more range. The opposite is true... narrow band has better range. Wide has better audio fidelity. Wide receivers have less usable sensitivity than narrow bandwidth receivers because the wider the receiver, the more it fills with the broad spectrum noise. It then takes more desired received signal to pull the data out of the noise, reducing range per watt. This is why major manufactures collectively agreed, many decades ago, that 2.5 kHz bandwidth for SSB voice transmissions would be considered "normal" bandwidth. Also, the "bandwidth" and "channel spacing" are not the same. It looks like you may have mixed them up. In real-world application, GMRS WFM (aka wide band) "channel spacing" is 25 kHz and the typical occupied bandwidth is 20 kHz. The NFM (aka narrow band) channels are spaced 12.5 kHz and are typically 11 kHz occupied bandwidth. I measured one of my radios moments before posting this. My radio on wide band is 19.3 KHz with 4.4KHz deviation and narrow band is 10.3 KHz with 3.5 KHz deviation (a little hot). In laymen terms, the more bandwidth you use, the more data you can send. The more data you send, the better the fidelity can be. In GMRS voice, that data is your voice. Therefore, on wide band, you can have better audio fidelity due to more information transmitted and received. The reason audio from a narrow band transmission has low audio on a wide band receiver is because the receiver is tuned in such a way that it is listening to a wider spectrum of radio than the transmitted signal, and it is expecting more deviation than provided for the voice. The empty RF space is filled with random noise (same noise that reduces sensitivity / range) and the lack of deviation leads to lower audio levels. You combine the two and it can sound like less than half the expected/normal audio levels. The inverse is true when a narrow receiver hears a wide signal. The receiver is only hearing about half the signal (making it sound lower in tone) and the over-deviation causes a loud audio level... sometimes sounding a little distorted.

Now all I need is a Repeater! ?