Best capacitors to use for se/30 recap ?

[srieck]

Sounds easy enough but with my tag end coming out of the C5 negative hole in the board I might need to improvise on that one...Are you still selling these caps ?

Also does my "fix" for C5 work in theory or is there something I don't understand? Looks straghtforward...the pad connected directly into the hole where I found the tiny solder dot (which was created on the other side of the board)...There do not appear to be any other traces there so if I can get the C5 neg lead connected to that dot...it should work i hope?

I'm being very careful about cleaning around the traces and it all looks clear and clean to me.

 

[srieck]

To correct my earlier post - I know it's C4 not C6 that is the 1uf/50v

What about those big electrolytics? C2 and C11 I think...should I swap these out? They look like there in good shape.

Sorry for all the questions but I noticed on my original SE (68000) logic board, there are no surface mount caps...just the original electrolytic ones and they look original and not popped or leaking. That computers runs perfectly. Never a problem. So the question is do all electrolytics go bad eventually or do some last indefinatley?

 

[phreakout]

Srieck,

If your improvised solution for C5 doesn't work, I traced the connection out and the negative pad DOES connect with CHASSIS GROUND. So, in a pinch, you could solder a small gauge wire from there to any point at ground, such as the metal bracket behind all the connectors on the rear that the outside bottom Torx screws fastened with.

Regarding that eBay link, those are polymer tantalum capacitors. In a pinch, those will work fine. I just didn't want you to reply on electrolytic caps. If you did, you would have needed to possibly redo the recapping 10-15 years down the road.

When Apple released the SE, they were still utilizing manufacturing resources from the last 4 models in the assembly line, which doesn't surprise that much. In fact, I liked it that way, since you could technically stop by Radio Shack if you needed replacement components. But a problem arose when the SE/30 and other models from that period were being developed: they ran out of space. So they had 2 choices: (1) use surface mount components, or (2) try and consolidate a vast majority of parts into a chip called the "gate array". The latter was done when the SE was introduced.

Electrolytic capacitors will go bad eventually, but not right away. They were built to be an alternative to the ceramic disc caps and primarily for use in circuits dealing with power, such as power supplies, amplifiers and regulators. They aren't meant to last forever.

73s de Phreakout. :rambo:

 

[srieck]

Thanks for taking the time to check that out for me phreakout! Makes sense that it would go to ground and that should be easy.