what do these trimmers do?

[wenzeslaus]

I'm sure you are all familiar with the Grundig FR-200. AM/FM and SW in 2 bands.

took it all apart working on some other stuff, what do these trimmers do? and I don't see anything for FM

also VC1 and VC2 have screws sticking out all crooked. VC1 isn't even on the PCB straight. what's up with that? and what do they chage when you adjust them?

 

[wenzeslaus]

it says GR-88V03 YBJ 03.9.26

must be a PCB from a GR-88 made by Tecsun, September 2003