Osborne 1 - Restoration

Osborne 1 - From Osborne 1 - TechWiki

Cap Lists

ASTEC Power Supply

C1 0.01uF 250v X Safety Cap
C2 0.1uF 250v X Safety Cap
C6 100uF 250v
C7 100uF 250v
C8 220uF 10v
C11 0.01uF 250v X Safety Cap
C15 1000uF 25v
C16 1000uF 25v
C17 1000uF 25v
C18 330uF 16v
C19 330uF 16v
C20 470uF 25v
C21 2200uF 16v

To note : The Osbourne (Not labelled as 1) carries the same PSU from my secondary re-build on the 27/7/2022 at the ACMS WorkShop.


Are the Safety Caps the RIFA capacitors that explode?
Can this be used as a replacement? Polypropylene Film Safety Capacitor having the same specs?

When it comes to the AC side you should consult a professional, but as long as the UF rating is the same and the VA rating is the same or higher, I believe that Polypropylene are acceptable, but may not actually filter as intended. Another member here @Jon is likely more able to offer an explanation.

In addition to the above, you should make sure your substitute is of the same “Class” as the original. Class-X (mentioned above) are intended to be hooked up between line and neutral and are designed to fail shorted. Class-Y are intended to be hooked up between line and ground and are designed to fail open.

More details here if you are interested: https://www.allaboutcircuits.com/technical-articles/safety-capacitor-class-x-and-class-y-capacitors/

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