Hi all, I recently had a system repaired from "no AV" to "almost working" by having the quartz timing crystal replaced. Now, I get AV but the signal has some issues - sometimes it has lines briefly across the screen, or sometimes the audio pops for a second. Almost like there is a small amount of interference in the signal. But there's something else slightly worse - during the games included in the system, there are many flickering black lines across the screen as well as input issues. Weirdly, I can only play these games if I use one hand to hold down one of the buttons in the top row of the calculator pad on the system. If I do this, the AV issues and input issues disappear and I can play normally. Cartridge games do not seem to have this problem.
I have tried taking out the RF box and cleaning the contacts (both the port and connection to the board) with alcohol as best I could without opening the box itself, but this has only helped a little, if at all. I'm wondering if there's anything I need to replace, short of just trying everything. New RF cable, new RF box? Something else completely? Any help is appreciated. For reference, the system is a Bally Computer System. I can provide more model numbers or a video if that would help diagnose.