Just picked up a Black Knight and the displays have a weird scrolling effect. Displays "scroll" left to right, if you can imagine each digit fading in and out, but timed such that the digit to the right fades on just after the digit to the left, and the digit to the left fades out just before the digit to the right, so you can only see 3-4 digits at a time, the others are off, and which digits you see scrolls from left to right. P1 and P3 scroll in sync, as do P2 and P4. Credit display also "scrolls".

Any thoughts?

I have a PSU rebuild kit I was going to use, but it seems like it may be a data issue. Anyone ran into this before or have any ideas? Re-seating connectors didn't help. Issue with strobes (shared between P1 and P3, and P2 and P4)? I've never worked on those before, I suspect parts are hard to get a hold of?

I realize now "scrolling" may imply the numbers move left-right, that is not the case, only the brightness of the digit changes.

I'm pretty sure I have a full kit from GPE, including filter caps:

https://www.greatplainselectronics.com/proddetail.asp?prod=WAN-HVP-KIT

Bam, 100uF caps it was! Turns out this game had a System 6 PSU. Not sure how common that is, but it's working now! Thanks!

Yeah, I had everything but the 5VDC filter cap (although I suppose I could have used a computer grade electrolytic...), just ordered some.

Thanks again!