WRQL370

It’s already answered for you with shortening the antenna. Your repeater channels are transmitting at 467. That’s at the edge of the band. Antenna is tuned way lower currently.

WRQL370/S was not on .575. It was on .725

Anything you ever wanted to know about the Gm300’s can be found at https://www.repeater-builder.com/rbtip/

Ok, that’s in the subscriber radios , and wouldn’t be on the receive of a repeater, it would be a setting on the transmit. But even with that set , it only drops the PL or muting the receiver of the subscriber radio, if programmed to CTCSS/DPL before the carrier drops to eliminate the squelch tail noise. But unless the signal is full quieting, will still exhibit noise. When a repeater is programmed to not have a hang time, it’s exactly the same on the subscriber radio transmitting like simplex. When you un-key, that’s it, there is no signal coming back immediately

I'm looking through codeplugs for 4 of my repeaters, and none of them have a setting for " squelch tail"

You can use two repeaters , one duplexer with a combiner, but you have to keep the frequencies close together so everything falls within the pass/reject band of the duplexers. The duplexer tuning will have to be slightly staggered so you take a bit of performance hit, but if you don't have tower space for a dedicated RCV antenna and a rcv multicoupler with a pre-selector, it could work. The down side is the cost of a combiner. Even two channel hybrid combiners are salty used.

The only problem with no hang time is the kerchunking morons tend to keep doing it expecting to hear the tail. eventually they give up though.

Negative, What you are referring to is called the hang time. That is the amount of time the transmit carrier is present after the station stops receiving an input signal. This is done to keep the transmitter from constantly keying and un-keying from a loss of marginal received signal There are options in higher grade repeaters to setup timing for reverse burst, or to stop the PL before the carrier drops to eliminate "squelch tail".

"How to attract more young people into the Amateur Radio Hobby" Ill say it, and this goes for many, Stop being creepy.

This is poor advice. You don’t jump on someone’s repeater unless you have permission to do so and you certainly don’t just use it until told otherwise. Some repeaters may still be leftovers from when businesses were licensed on those frequencies, and regardless, at the end of the day, the repeaters are private property of the owners. While the airwaves are not, the repeater or this method of using them is, and by using a repeater without permission is basically unauthorized use of private property. This is the same as coming across someone’s yard or land, and just using it until you are told otherwise or thrown off. Until you identify who’s repeater it is and make contact with the owner or responsible party, treat it as a closed repeater and stay off it.