1970s Quasar TV won’t tune to picture

[VHFUHF]

Hello all,
I came across an old Quasar set that an acquaintance wanted to get rid of. She hadn’t really used it in awhile so I went ahead and tested it, and it powered on smoothly to some static. I’ve been messing with the thing for awhile (hooked it up to a converter box) and I can’t seem to get the picture to fully come through. I adjusted the vertical and the VHF screws, but the best I can get is still very scrambled. You can see the flashes and scrambled credits and scene transitions or when words flash on the broadcast, but that’s it. The sound comes in crystal clear though. When I change the dial to a different channel, the screen seems normal, the standard ‘snow’ comes through and there appears to be no issue with the picture.

Sadly, I cannot make out any model number on the set due to damage to the original stickers. Only thing I can really make out is that I think the set is from ‘77. I can barely make out the service number, wt5985sw, which appears to match the model number as well. I attached some pictures, any advice is welcomed and appreciated. I’d love to get some use out of this thing!