Batboard

I have found some good references on this site about making a GM300 repeater system but needing some help as I am still new at this.
My setup is this
1.I have two GM300s 16 channel setup in the repeater mode with a duplexer.
Note: works but when transmitting through the repeater from truck to truck the audio sounds like it overdriving the speaker, allot of base.
2.I read the web link on Non-R.I.C.K. Interface Cable and are these pins the only ones I need to hookup for the CROSS-CONNECTION between the radios or are the others? Radio1 Radio2
PIN 3 PTT ___________________ PIN 8 COR
PIN 8 COR ___________________ PIN 3 PTT
PIN 5 TX Audio __________________PIN 11 Disc Audio
PIN 11 Disc Audio __________________PIN 5 TX Audio
PIN 7 Gnd ___________________ PIN 7 Gnd
3. I have cut the watts on the TX radio and out the duplexer am getting almost 25 with good 4-inch fan mounted to the heatsink as this will be a low use repeater.
Note: I have read a couple of different things about putting a trim pot in but still not sure if I am doing this between my PINs or I need to do this on the logic board it self. Correct me if I am wrong but it almost seems like the receive audio gain is over doing it. The voices are not distorted just like it’s too much. Any help for this novice would be appreciated.

Number 1 you do NOT use the discriminator out put or the pin 5 input for what you are trying to do. Pin 5 bypasses the transmitter audio (modulation) limmiter stage and will over dev the TX.

Do a search here for Todd's hookup.

Thanks for the reply will look for that, I did find some useful things on this link

http://www.storm.ca/~nand/990/RICK/rptr.pdf

That PDF is what I refered to, not a bad way to do it.. works fairly well.

Pin 11 should provide muted filtered recive audio.

Got one put together today and it controls the audio real well. Going to make three backup repeaters just in case our mains go down should be a good temp option to have. I have looking to see if it's possible to do the Motorola Radius M1225 4 channel mobiles but I don't see it in the software for some kind of generic repeater setup.