Need some help on the 82A ladder sight on my Win 52|Winchester Sights|Forum|Winchester Collector

Also some questions on that 82A sight, I may change the sight later but I want to try shooting it as is.
This is a Winchester that has had the wood refinished but the barrel wasn’t re-blued. I think it was before the speed lock addition. I think the knobs at the bottom are for windage and the slide is elevation. In my pic at the top on the left there is a rotary knob, what does that do? BTW I only made this thread because I didn’t get any clear answers on YT or other websites.
One more, I read somewhere that for closer distances you don’t need to raise the ladder, but when I tried that I did not see any ‘V’ at the rear. I assume at short distances the slide in the ladder is close to the bottom. Luckily .22 LR ammo is cheap so the learning curve won’t cost much. The serial number was 15XX.

I’ve got pics but the site won’t allow me to post them.