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Hello All. I finally put together a base station for the house. I'm using a Kenwood TK-880-1 purchased from ebay, a 30 amp power supply from ebay, about 30 feet of LMR-400 type cable and a Tram 1486 antenna tuned for the GMRS band. The power supply is a bit overkill as the max needed would be 8 amps for this radio. But I didn't want to have to replace it if I later upgrade to a higher power GMRS radio. Today I was able to make my first "radio test" to a repeater (WRPD520) about 21.5 miles away using the TK-880 on high power, about 19.5 watts, with 1.25 SWR.

The question was answered by the first 5 words. It's just that OffroaderX never learned to read.

Jeesuz.. "Some people" could over-complicate a spoon in their desperate attempts to show everyone how smart they think they are. The answer, which unbelievably even after all those words was still not actually answered, is: NO

Proper coax is length neutral (it is 50ohm at the transmitter, and it is 50ohm at the antenna) -- that CB suggestion is just masking a problem by adjusting the coax so that the /nodes/ in the standing wave don't appear at the point of measurement. The SWR is still mismatched. https://www.ad5gg.com/2017/06/11/coaxial-cable-length-does-not-change-swr/ Heck -- even ignoring standing wave nodes, if you use a long enough coax and measure at the transmitter you will achieve a perfect SWR... You won't be reaching anyone, but you will have a perfect SWR. SWR is based on the power sent to the antenna, and the power reflected from that antenna. With a very long coax, you have power losses in the coax itself, all the power sent/reflected could be lost as resistive heating of the coax so there is no measurable reflected power, but also no power going out the antenna. The ideal is to measure SWR AT THE ANTENNA (or at least close enough that your body and measuring tools don't interfere with the feedpoint match). Of course, if the antenna has a permanently affixed cable you'd have to either learn to splice connectors into the cable or do the measurement from the end of the provided cable.

How do I join the myGMRS Network?

Thank you WRKC935 for explaining vertical separation as well. Many get caught up on horizontal separation of antennas, with zero mention of vertical being an option and often used by commercial users on radio towers. For the OP, just get a duplexer, they are fairly cheap now and work better than two antennas, coax, and figuring out where to place them. Keep it simple and you will get better coverage/service with less maintenance and complexity as a result.

REACT INTL ZELLO TEAM CHAT from Glendale? (actually looks like Gorman) looks like a possible better fit. It is in the coverage area and as the name states it’s on Zello. ...at least the map claims to have the coverage FWIW.

As @WRXE944 mentioned, color codes are a DMR thing, and not applicable to gmrs (currently, anyway, who knows for the future). On the second item, it CAN be done to have a repeater accept more than one tone, it can be assigned to different users, or configured for local repeat vs also passing audio to linked repeaters. However, unlike DMR (and the time slots), it doesnt allow more than one user to use the repeater at the same time.

I guess, I mean he’s a dog so who knows why he says what he does ?

Seems an odd way to tune a window filter for a RX multicoupler. And damn wide to boot. Mine are 466 to 470 for 461 to 465 inputs. And there isn't any 465 around these parts. We top out at 464 with any license I have dealt with. The other window filter (yes I have two) is tuned to 446 to 450.5 for ham repeaters. And I assume you are on a TX combiner?

Here is a screen grab of what my settings are... Radio Configuration --> Radio Wide --> Tx Audio Control Per Mode. It's the Noise Suppression check box and Attenuation Level option. The directions say it works best with the Mic AGC disabled, but I find it works best with it on.

Basically, turn it on, select a channel, and push the button while you talk. As for additional programming, what does the User Manual have to say about that?

Gonna get into the weeds here with an explanation. First is antenna separation and attenuation. And an understanding that a duplexer will provide about 90dB of attenuation. Two UHF antenna's that are mounted VERTICALLY apart on the same tower leg, will provide about 20 dB of attenuation. Two UHF antenna's separated by 80 feet horizontally will provide the same 20 dB of attenuation. So if you had a 150 foot tower, and put the receive antenna at the top and the transmit antenna at about 10 feet you MIGHT get 60 dB of attenuation. Still not as good as a duplexer. Now, lets look at the dollars and cents of this. First off you will need some sort of hardline for an install like this. And it's gonna be two runs. Lets say the tower is 30 feet from the building and it's another 20 feet to the radio. So you will need an extra 50 feet of hard line at 4 bucks a foot. Four additional connectors at 25 bucks a piece, two for the ends and two for the additional 90 dollar surge suppressor for the feed line. Then you need two antenna's. A USED DB-408 is about 150. So lets do some math. 50 feet of cable and four 25 dollar connectors comes up to 300 bucks. Now the additional 150 for the antenna, that's 450 bucks plus the surge suppressor and the labor, so 600 bucks for that additional LOW MOUNTED antenna that is gonna talk like crap because it's 10 feet off the ground. To save you HOW MUCH for a duplexer? Hell a new pass notch set is 1300 and used they are around 500 or less. So it's actually CHEAPER to run the duplexer and do it right and have it perform in a manner that would be acceptable. Yeah, gonna go the route of the duplexer every time. Oh, and you say you are gonna cheap out and run RG-8 or 9913 and not hardline. Sure... you are gonna run the RX cable down past the TX antenna in the near field of said antenna and expect the shielding from a BRAIDED CABLE to block 100% of the signal in the near field of a transmit antenna. Sure... have fun with that too.