SteveShannon

In your vehicle or your house?
In your house just use a 115vac power supply  
In a vehicle using an inverter to get 115vac and then a 115vac power supply to get 13.8vdc is inefficient. Just run it off the battery. Your output will suffer very slightly when the engine is off because your battery probably provides 12.7vdc then. 
 

Connected to C201-R201-R202-L200 filter. Looks like an input for a secondary receiver, behind the antenna switch. Maybe for scanner working off the same antenna? That would explain BNC connector too.
Clever, I need to remember this for possible future installs.
Edit: the more I look at it, the more I think this is for a scanner working off the same antenna. The tap is behind the antenna switch (to not fry the receiver) and before the L203 band pass filter (to keep wide band receive). Refer to page 28, fig 2 in service manual.

The i20r controller he had sent CW ID in CSQ mode. Only PL was on when the RX radio received the PL (tones). The Communications Specialist controller does the same thing. Its all how the controller is programed and radios are programmed. Built many of those repeaters when i was at the shop with the i20, zetron, comm spec and other controllers at the time. Most commercial controllers will accomplish what the user is looking for. A ham/hobby controller will not. 
@mikevman I'd search ebay for a CommSpec TP3200, CSI 32, Zetron CR-310 or any of the Trident controllers. They pop up on and off but finding one the size of the i20 may be challenging. Most are 19" rack mounted. 

This got me curious. Some forward thinking ARES groups do include GMRS in their plans. It would be silly not to. If the goal is to communicate as widely as possible to those people who are affected by an emergency or those people who can help during an emergency you don’t turn up your nose because it’s not amateur radio. You use every means possible and you plan to succeed. 
https://www.aresd1.com/post/ares-district-1-deploys-to-hobart-for-simulated-emergency-test

Couldn't you just leave the CW ID blank when configuring the controller?

I’m curious if they have a pudgy duck antenna that wouldn’t have that gap. ?

There is some sort of glitch that I have not figured out yet:
Programmed as shown in the Screenshot above, and left on Channel 22 when programmed it works.
But once it is on another channel and then manually set to Channel 22 and then turned off and then on, it is not working.

I was wondering how this would work on a radio with only a channel display and two knobs.  This doesn't seem to be a feature I would use on this radio, but thank you for pointing it out.

Use a different manual ?
http://www.pofung.cn/UploadFiles/20200827094748361.pdf
 
It explains that you must have all 22 channels programmed and then power on while on channel 22. It will automatically begin scanning:
Scan
This function can be activated only by means of the optional programming software. To enable the Scan function, all 22 channels must be programmed. If you turn on the radio on channel 22, the scanning will automatically start. Whenever any signal is detected, the scanning will stop on a busy channel. If the PTT is pressed, you will transmit on the latest busy channel. Channel 22 is the priority channel; therefore if you don’t pick up any signal when you press PTT, the radio will transmit on channel 22.

Thanks, folks.  I've got The ARRL Antenna Book, 23rd Edition (all 1000 pages!) and Reflections III.
Looks like about three months of reading.
Well, I asked for it!?

Probably the best way is to pick up something like the ARRL Antenna book and then watch some videos that teach the use of EZNec or MMANA, which are two antenna modeling programs.  Free versions of each are available and they’re pretty easy to use.  Look for a channel on YouTube by DX Commander that has some tutorials on MMANA or David Casler on EZNec.
I would try going to a ham swap meet and getting a used copy of the book; it’ll cost much less than ordering from ARRL and the difference will be minimal.  Antenna theory hasn’t changed much lately, except for the gigahertz regime.  There haven’t been any landmark discoveries that have changed people’s minds for awhile.
I receive a big book quarterly of the Transactions of the Antennas and Propagation Society of the IEEE and I almost freeze at the titles of the articles. I think I’d have to go back to school just to understand the titles, much less the actual articles, but every article is about gigahertz or terahertz uses.  As far as I can tell the UHF stuff is relegated to the same dusty shelf as VHF, and HF.  There’s probably something still being done for ELF also, but I haven’t seen anything.

The meter is what some of us refer to as 'close enough' for what we do.  Keep in mind, the meter is user adjustable. It likely is calibrated fairly close from the factory. 
You want to keep your SWR under 3:1 for best performance.  I wouldn't touch it.

Results are inconclusive without the proper testing equipment, however signal is being radiated from somewhere, so it either can't reach the PA, or PA is shot. The supply voltages on PA are correct, you confirmed it. I'd try to test AC voltage when keying mic at the Q7, Q202, Q204, Q205. Oscilloscope would be very handy here.

Couldn't you just leave the CW ID blank when configuring the controller?

Probably the best way is to pick up something like the ARRL Antenna book and then watch some videos that teach the use of EZNec or MMANA, which are two antenna modeling programs.  Free versions of each are available and they’re pretty easy to use.  Look for a channel on YouTube by DX Commander that has some tutorials on MMANA or David Casler on EZNec.
I would try going to a ham swap meet and getting a used copy of the book; it’ll cost much less than ordering from ARRL and the difference will be minimal.  Antenna theory hasn’t changed much lately, except for the gigahertz regime.  There haven’t been any landmark discoveries that have changed people’s minds for awhile.
I receive a big book quarterly of the Transactions of the Antennas and Propagation Society of the IEEE and I almost freeze at the titles of the articles. I think I’d have to go back to school just to understand the titles, much less the actual articles, but every article is about gigahertz or terahertz uses.  As far as I can tell the UHF stuff is relegated to the same dusty shelf as VHF, and HF.  There’s probably something still being done for ELF also, but I haven’t seen anything.

Well, that does put you in the same range as an HT on high power, so...
Any reasonable straight freeways... "Mile" was just a suggestion -- mostly I was thinking of increased range than normal "convoy", IF you were running higher powers.
Narrow band for GMRS is 12.5kHz using an 11kHz modulation width, deviation [how much the FM signal swings around the nominal frequency] is even less. Normal GMRS is a 20kHz band (some rigs don't support 20kHz and are actually 25kHz, commonly using a 16kHz modulation. The deviation tends to track "volume" while the rate of deviation indicates the audio frequency (high pitches "vibrate" +/- the stated radio frequency faster than lower pitches). So... 11k modulation doesn't swing as far as 16k modulation -- on a radio configured for GMRS (20kHz), the smaller swing translates to quieter audio. Going the other direction, the wider swing may be clipped, causing distortion in the audio, and will sound louder/compressed [less volume variation relating to actual voice changes].
For true GMRS, only the channels 8-14 (in the 2017 combined numbering scheme) are NFM. ALL true FRS radios are NFM on all channels.
You may still want to evaluate line noise at the battery. Do you sound different if you disconnect the charger and rely ONLY on the isolated battery? It will be lower voltage, so your output power might be lower, but if you were running on a 5W channel, probably not much change.

Even setting up a ham radio for use with GMRS repeaters can be challenging for us simpletons.   But a GMRS radio like the KG1000G or XS20G is very easy to setup. You dont even need the software, you can do it directly on the radio (but, it is easier with the software).
If simplicity is your goal for GMRS, then do not get a CDM1250, XTL5000 or a ham radio - get a GMRS radio.

Nothing looks wrong on this pic.
The voltages seem fine. Without the oscilloscope with 500MHz bandwidth it's hard to diagnose. However, if you put your multimeter (totally not rated for 500MHz) into Voltage-AC mode, and check pin 1 when pressing PTT, and you see <anything>, the signal goes in. Now, do the same test on pin 4, where the amplified signal should be. Keep antenna or dummy load connected.

America is also commonly used to mean the United States of America. From Wikipedia:
The United States of America (U.S.A. or USA), commonly known as the United States(U.S. or US) or America, is a country primarily located in North America.

Ahh, screw the day job, this is fun. Here is the excerpt from the service manual, page 72:

 
Notice the R:0.01V T:7.52V (in pink) close to the bottom-left corner. So, maybe 7.88 is not too high, after all.

oh wow, ok. I just read through the data sheet again (I may have to read it a few times) I just checked that voltage regulator that I put in. It was showing 13.8v  / gnd / 7.88v so pin 2 of the PA is getting that 7.88 from the volt reg so I guess I can start from there, or should it actually be 6v? I guess the 17v is like the maximum?
At least I can hold off on buying a new PA for now. I know I'm probably putting more into this old radio than it is worth, but it's kind of fun trying to figure it out

Btw, the service manual with the schematics for the V2.0 version of the radio is here: http://www.repeater-builder.com/kenwood/pdfs/tk-880h-svc-man.pdf
I'd walk through it it with you, but I'm busy at my day job right now. LOL

Careful here. Pin 2 is 6V, Pin 3 is 17V. Refer to the table on Page 2 in the datasheet.
Edit: these are max values, so Pin 2 should be around 5V, and Pin 3 is around 12V.

Yes, this is the part. I agree with Sshannon, oscilloscope would be needed. But here is the datasheet for the PA, just in case: https://www.mitsubishielectric-mesh.com/products/pdf/ra45h4452m.pdf You can quickly check the voltages on pins 2 and 3 (refer to Page 2 in datasheet). Maybe the PA is fine, but there is no driving voltage. It also may have an effect on the audio amplifier.

Use a good quality lightning arrester where your coax enters the house and ground it. If you know a storm is approaching you should disconnect your radio from all external cables: power, ground, and coax. 
If you want something that is more resilient then there’s a document that describes how commercial communication sites are protected. Nobody goes to them and unplugs everything when there’s a storm. I’ll post a link: https://www.blm.gov/sites/blm.gov/files/Lands_ROW_Motorola_R56_2005_manual.pdf
 
Meanwhile here’s a short video: