SteveShannon

More people should take a few minutes out to help somebody in need. The world would be a more pleasant place to live in. 
I spent half of my weekends for about a year or so along with my two sisters taking a shift to look after my Mom before she passed away. She had advance dementia and needed at home 24/7 care. The insurance only covered half of the cost of at home hospice care while the rest came out of their retirement savings and our volunteered help. 

Exactly.  The reason I ordered the UV380 was because I’d been programming code plugs for a blind/deaf (mostly) ham friend.  The OpenGD77 and OpenUV380 software supports a fairly rich set of voice prompts which are a huge benefit to my friend.  For the Anytone/Alinco model I found that the only way to make channels easier for him were to exactly duplicate the channels for every DMR zone. That way he could memorize the numbers of the zones and the numbers of the channels within the zones.  So, channels 191, 291, 391, … all pointed to Talk group 91, the North American talk group, differing only in zone number. But as you say that’s a lot of duplication and ends up with many channels that differ minimally.  The OpenGD77 model is much more intuitive.

👍🏼

Normally when the 7/8 hardline enters the building/shelter it goes to a polyphaser on the bulkhead. From there you would use 1/2" superflex to the N on the kenwood. 7/8" is the feedline for the tower only. 
 

Hi John,
For GMRS and FRS, the FCC has designated 22 specific frequencies for our simplex use and 8 more for transmitting to the repeater. 
The channels are interlaced. So tuning to an “in-between” frequency might be interfering with other services or other channels. 
You’ll definitely want to read the regulations to see what frequencies we are allowed and the power and bandwidth:

§ 95.1763 GMRS channels.
The GMRS is allotted 30 channels—16 main channels and 14 interstitial channels. GMRS stations may transmit on any of the channels as indicated below.
(a) 462 MHz main channels. Only mobile, hand-held portable, repeater, base and fixed stations may transmit on these 8 channels. The channel center frequencies are: 462.5500, 462.5750, 462.6000, 462.6250, 462.6500, 462.6750, 462.7000, and 462.7250 MHz.
(b) 462 MHz interstitial channels. Only mobile, hand-held portable and base stations may transmit on these 7 channels. The channel center frequencies are: 462.5625, 462.5875, 462.6125, 462.6375, 462.6625, 462.6875, and 462.7125 MHz.
(c) 467 MHz main channels. Only mobile, hand-held portable, control and fixed stations may transmit on these 8 channels. Mobile, hand-held portable and control stations may transmit on these channels only when communicating through a repeater station or making brief test transmissions in accordance with § 95.319(c). The channel center frequencies are: 467.5500, 467.5750, 467.6000, 467.6250, 467.6500, 467.6750, 467.7000, and 467.7250 MHz.
(d) 467 MHz interstitial channels. Only hand-held portable units may transmit on these 7 channels. The channel center frequencies are: 467.5625, 467.5875, 467.6125, 467.6375, 467.6625, 467.6875, and 467.7125 MHz.

My brother runs his mobile radios on a 100AH LifePo4 battery. He charges it with a LifePo4 charger plugged into the 120V inverter built into his truck. He does this so that he doesn't have to try and get power wires through the firewall since he does not keep his trucks very long. I've never heard him complain about RF issues with the radios.
Definitely get the correct charger for LifePo4 batteries if that is what you are going to use. A standard charger will ruin the battery. And there is a difference between regular lithium batteries and LifePo4 batteries.
Note: my brother uses a 100AH battery in the truck since he also uses it for Parks On The Air with his 100 watt Icom IC-7300 HF radio. You can definitely get by with a smaller battery for a 50 watt radio and even smaller one for a 20 watt radio.

On GMRS certified radios the channels [1-30] are already programmed. Channels 1-14 should have 4 digits after the decimal like 462.5625. These all end in 5 - they're 12.5KHz above and below the frequencies for channels 15-30. If you do a search you should be able to find a chart to help you visualize the relationship.
 

Hi John,
For GMRS and FRS, the FCC has designated 22 specific frequencies for our simplex use and 8 more for transmitting to the repeater. 
The channels are interlaced. So tuning to an “in-between” frequency might be interfering with other services or other channels. 
You’ll definitely want to read the regulations to see what frequencies we are allowed and the power and bandwidth:

§ 95.1763 GMRS channels.
The GMRS is allotted 30 channels—16 main channels and 14 interstitial channels. GMRS stations may transmit on any of the channels as indicated below.
(a) 462 MHz main channels. Only mobile, hand-held portable, repeater, base and fixed stations may transmit on these 8 channels. The channel center frequencies are: 462.5500, 462.5750, 462.6000, 462.6250, 462.6500, 462.6750, 462.7000, and 462.7250 MHz.
(b) 462 MHz interstitial channels. Only mobile, hand-held portable and base stations may transmit on these 7 channels. The channel center frequencies are: 462.5625, 462.5875, 462.6125, 462.6375, 462.6625, 462.6875, and 462.7125 MHz.
(c) 467 MHz main channels. Only mobile, hand-held portable, control and fixed stations may transmit on these 8 channels. Mobile, hand-held portable and control stations may transmit on these channels only when communicating through a repeater station or making brief test transmissions in accordance with § 95.319(c). The channel center frequencies are: 467.5500, 467.5750, 467.6000, 467.6250, 467.6500, 467.6750, 467.7000, and 467.7250 MHz.
(d) 467 MHz interstitial channels. Only hand-held portable units may transmit on these 7 channels. The channel center frequencies are: 467.5625, 467.5875, 467.6125, 467.6375, 467.6625, 467.6875, and 467.7125 MHz.

There are some things to be careful of.  If you get a LiFePO4 battery and intend to charge it from the alternator, there are special chargers that need to be used to avoid burning out your alternator.  There are lots of YouTube videos about it.  I haven’t done it and have no experience.

Doesn't have to be perfect, just tolerable to those on the other end. I don't want to be "That Guy"! Thanks again, Steve. 

Yes, it’s possible. A secondary battery would be the most efficient and have the least opportunity to create noise, but there’s no guarantee it’ll be a perfect cure.

That's why I have those channels set to not transmit on my mobile units. They're there, and if I have a good enough reason, I can fairly quickly turn the transmit feature back on. Having them in the radio means I can listen and even scan them if I want. So far, I haven't felt the need to do that, but it's an option.

Hopefully you get your interference issues figured out. I know RFI can drive a person crazy trying to chase down.

Alternator was 17 years old and I found one at a higher amperage so I went ahead and replaced it. I grounded the antenna and felt that 3 bolts in the alternator should provide a good ground. I may strap it too. Ferrite beads on Alternator to battery cable, radio power supply, coax, and a few nearby power leads. I was going to place the chokes on the LED headlights as well, but there is no interference when I turn them on. It's only when the engine runs.
The spark plugs and wires are about a year old. Plugs are resistor type and the cables are not the very top of the line, but the better of the in-store choices.
Same whine. I ordered a filter today as a least resort.

My ole eyes and brain just did not compute this knowledge until, NOW!  Thanks to all that asked and to those that answered!
I kept seeing the words "Mobile GMRS" and thinking my MXT-400 qualified for that.  But then comes along...
"467 MHz interstitial channels. Only hand-held portable units may transmit on these 7 channels. The channel center frequencies are: 467.5625, 467.5875, 467.6125, 467.6375, 467.6625, 467.6875, and 467.7125 MHz.
So now I realize why I don't have those channels in my radio!  We had this exact problem on the trails (Trail Guild wanted to use CH 10.....) now it sinks in after studying this, again Thank you all~!

No kidding!  We go there every Sunday for breakfast.  They have a piece of my artwork on the wall, too.  Meet us there!  0900 ish.

No, I know of Wilsall 😁. My dad’s cousin owned the Clyde Park Tavern in the 70’s or 80s.  

Nothing about the general personal radio services regulations nor those of part B (FRS) or part E (GMRS) support the position that a licensed user has a greater right to the 22 shared channels. 

It wasn’t a stupid question.  

It wasn’t a stupid question.  

I'm going to close my post out with something that will piss some people off, and others will say I don't know what I am talking about... so if you don't want to read all of the post, you may want to skip to the END.
 
The reason CB went to the wayside isn't known for sure, but I have a few ideas.  Modulation type isn't one of them.  I think there is zero chance of CB replacing FRS.  I don't think it could even take a significant part of the market, and I will explain why.
First, people get extremely frustrated because their mobile CB radio performs so poorly, with regard to range.  As mentioned above, that is almost always due to the antenna.  The primary problem is, the average DIY person doesn't poses the tools or skills to properly install a CB and antenna, nor verify if it is working correctly.  This wasn't always the case, but somewhere in time, this common knowledge kind of vanished, leading people to think they can just bolt on the antenna and life is good.
Then, there is the size of the antenna. The shortest proper length for a CB antenna is 104 inches.  That's not a type-o... that is over eight and a half feet.  Not everyone is willing to put an antenna that big on their vehicle.  So, you see everyone using a compromised antenna... like the 4' and even 3' firestik antennas.  I own a 4 footer and a 1 footer, but I know they are only going to work for a mile or less. 
FRS is at a frequency that only requires a 6" antenna, and the installation is way, way more forgiving.  Just by it's nature, its not common to incorrectly install an FRS antenna.  And when manufacturers put even shorter antennas on them, say a 3", it's no where near the compromise made in CB with a 3' antenna.
So, you take a radio and antenna that doesn't install correctly easily and complicate that install with an antenna that more resembles a dummy load than an antenna, and yeah, the performance is gonna suck.  Creating an even smaller, overpriced version in a handheld doesn't sound like a good time, either.
Now, there is also another issue to deal with.  While there are FM CB radios available, FM quality on CB is no where near the audio quality of FRS.  FRS radio uses a lot more bandwidth, which means the signal can carry more data, aka higher fidelity audio.  Many people will prefer FRS just because it sounds better. 
 
END
Now to upset some people... I believe that a properly installed mobile CB and antenna or a quality CB handheld will outperform an FRS radio 100% of the time.  I also believe that a properly installed mobile CB and antenna AND a quality CB handheld will outperform their counterpart in GMRS radio a vast majority of the time, when it comes to P2P comms.  The two top reasons why GMRS has made it to the top of the pile is due to repeaters and the frequency used is ideal for heavily wooded and dense urban areas.  While generally, I believe CB is superior in many cases, it seems that US radio use in dense woods and cities are the most common use cases... hence GMRS (and FRS) win over mobile and handheld CB.

This doesn't sound like the best use of GMRS and based on what I'm reading here, it really seems that the OP's area is ripe for a decent 2 meter repeater setup.
The amateur radio Technician's License (to start with) isn't terribly hard to get and with that, one can use those 2 meter frequencies and legally maintain the gear.
I would think that the local emergency infrastructure would welcome additional communications and it would likely be easy to get tall tower space somewhere. Our club has a repeater antenna up on top of a local water tower. The initial setup is relatively expensive, but donations can often defray the costs.

Here is a full list of all the FRS/GMRS channels.
https://www.buytwowayradios.com/blog/2022/11/list-of-gmrs-frequencies-and-channels.html?srsltid=AfmBOopMy04seYsWSiiA4DFSusU7BoworzqVnVNJg83cZ5PuwO9Wl5V7

Hi John,
For GMRS and FRS, the FCC has designated 22 specific frequencies for our simplex use and 8 more for transmitting to the repeater. 
The channels are interlaced. So tuning to an “in-between” frequency might be interfering with other services or other channels. 
You’ll definitely want to read the regulations to see what frequencies we are allowed and the power and bandwidth:

§ 95.1763 GMRS channels.
The GMRS is allotted 30 channels—16 main channels and 14 interstitial channels. GMRS stations may transmit on any of the channels as indicated below.
(a) 462 MHz main channels. Only mobile, hand-held portable, repeater, base and fixed stations may transmit on these 8 channels. The channel center frequencies are: 462.5500, 462.5750, 462.6000, 462.6250, 462.6500, 462.6750, 462.7000, and 462.7250 MHz.
(b) 462 MHz interstitial channels. Only mobile, hand-held portable and base stations may transmit on these 7 channels. The channel center frequencies are: 462.5625, 462.5875, 462.6125, 462.6375, 462.6625, 462.6875, and 462.7125 MHz.
(c) 467 MHz main channels. Only mobile, hand-held portable, control and fixed stations may transmit on these 8 channels. Mobile, hand-held portable and control stations may transmit on these channels only when communicating through a repeater station or making brief test transmissions in accordance with § 95.319(c). The channel center frequencies are: 467.5500, 467.5750, 467.6000, 467.6250, 467.6500, 467.6750, 467.7000, and 467.7250 MHz.
(d) 467 MHz interstitial channels. Only hand-held portable units may transmit on these 7 channels. The channel center frequencies are: 467.5625, 467.5875, 467.6125, 467.6375, 467.6625, 467.6875, and 467.7125 MHz.