I apologize for resurrecting an old thread but i thought it would be better than creating a new topic.

I need some help programing my newly acquired GP68 radio for use on GRMS frequencies. I have already found the frequencies compatible for listening to GRMS channels, but when i try to transmit all that is heard is a horrible screeching noise.
I have searched the interwebs to the best of my ability and am still having difficulties making this work.
any help would be greatly appreciated.

-JD