Picked up an Asteroids (Wells-Gardner 19V2000). It appeared to work fine before I put it in storage. After 6 months or so, I pulled it out to work on it. Now, the vector images on the monitor appear to fade in and out about every second. They don't fade completely out, but get dim and then return to normal (and it happens throughout the screen). I tried to attach a short video, but couldn't. I tried moving it to another working Asteroids cabinet (thinking it could be a power related issue), but it did the same thing. I read an old post where someone suggested this could be a bad HV diode. I'm going to cap it anyway, but I wasn't sure if this was really a cap related issue. What could be causing this fading? Thanks in advance for your feedback/guidance.

