Adjusting the CRT on the Neogeo
It’s been a while since I stuffed about with CRTs, and most of them I didn’t particularly give a shit about as they weren’t rare or expensive the last time I messed with them… the CRT in my Neo Geo is very different. It’s nearly 20 years later, they’re not exactly common now, and finding someone qualified or the gear to work on them myself is a bit difficult.
I don’t really have the right gear to adjust the convergence on it, as I don’t have a proper test pattern generator. I can get one for about $100USD, but for something I’d only use once or twice it seems like a bit of a stretch. I do have the various test patterns on the Neo Geo itself, but they’re not great, and I don’t have any way of cancelling the guns without adjusting them, which I wanted to avoid touching if possible.
But enough of that, the twisted yoke is giving me the shits and I decided to do something about it. Turned it off, discharged everything, undid the retention screw, and picked at the globs of silicone until I figured I could get it to move, and suddenly it did. Awesome! Fire it up with the test pattern, get it how I want it, and yep… that’s fucked the convergence. Not completely terrible, but not as nice as it was.
I pulled up the service manual for it, and followed it as best I could, and after a few goes I was fairly satisfied. The blue gun is still a tiny bit low around the edges, but I don’t think the rings will fix that. I can’t remember how it looked before but I think I have it almost as good once I adjusted the levels again correctly. I think I could get it better with a real test pattern generator, but I’m fairly happy with it now. Finally, everything is visible on screen, there’s no annoying black angles on the corners, I’m pretty happy.
Now if I could just find more time to play it!
Edit 2020-02-21: As it would happen, I found a shitty mobile phone photo of the test pattern before I touched it, and it turns out that the blue around the edges of the grid has always been off, so I’m definitely convinced I have it about as nice as it was before. It might be confirmation bias, but I feel like it looks better in-game than it did. Really wish I had a TPG to do it properly though!