Brief 8656A update here.
I guess I'm just going to have to do the work.
With this kind of issue in the supply rails, I've got to get a pretty solid test on the caps, bottom line, and that means lifting a leg on C17,18 and 19. I can quickly flay this board open and test these guys, that's not a problem, but here's where my mind is going -
Let's face it, these caps are 40 years old. Good caps originally for sure, and in circuit, they're not raising too much concern. But, yeah, they're 40 years old and there's ripple out of spec. on the rails they smooth.
I'm trying to get this old beast in a place to be a solid contributor on the bench. It seems inevitable that these guys are going to be replaced. Unfortunately, that "thought thread", runs headlong into the form factor problem.
I've got suitable axial replacements in my stash that could go in here. They are about a 3rd the size though. I'm going to have to come up with an appropriate mounting strategy for modern equivalents. The original zap-strap approach from the factory, won't work in the current arrangement for modern caps.
Not saying it can't be neatly done, but I'm just.............sayin'.
So, I'll test 'em, get good data, and strategize about how to get a replacement solution that's appropriate. I have to admit that I found the mounting solution by HP on these guys to be a bit "how ya' doin'" right out of the factory. I'll ponder for a bit.
Thanks again for the feedback.
JRH