ASTEC AA11040 - Replace or not?

[gvollmann]

Hi!

This my Apple II power supply (ASTEC AA11040) - do I have to replace the polyester caps C1 & C20? By what?

Thx for your help!

[eccerr0r]

Re: ASTEC AA11040 - Replace or not?

No, usually they don't fail, unless it's one of those old leaky Rifas which it looks like there aren't any ...

Was this PSU serviced before? I could have sworn these old apple II psus used Rifas.

[gvollmann]

Re: ASTEC AA11040 - Replace or not?

No, usually they don't fail, unless it's one of those old leaky Rifas which it looks like there aren't any ...

Was this PSU serviced before? I could have sworn these old apple II psus used Rifas.

Thx!
No service yet! I will change the other caps. In a second PSU I have this problem with the RIFAs - but already ordered new ones!

[PeteS in CA]

Re: ASTEC AA11040 - Replace or not?

Those Chemicon RX series output caps are 35 years old or more. I'd be worried about their health. If you have to replace them I'd try a really old "low impedance" series like Nichicon PS. Something much newer/better than that might cause stability problems. That TO-3 type switch device is an NPN transistor, probably 4A or 5A, probably designed for television horizontal deflection (in other words, nothing exotic).