Midland G9 plus trimmers

[avr]

Hi everybody,

I am looking for an image of the function of each trimmer in a midland g9 plus, but I can’t find anything.I want to adjust the squelch because my walkie is a bit deaf.

This is the PCB of my G9:



Thanks

[avr]

I have tested the trimmer near the white variable capacitor, as I see in one schematic, but it didn't do anything.