[Adam]

Here's a page from an RCA factory manual which shows how it works. Basically you turn those screws for the channels you want all the way clockwise, ones you don't counterclockwise. And it does have the fine tuning, push in the small knob over the push-bar and turn it, and it adjusts it separately for each channel. A different gear corresponding to each channel lines up with it each time the tuner rotates. The manual calls it "One-Set" fine tuning. If you want a bigger image of that scan let me know, that's the largest size pic I can attach.