68kMLA Classic Interface

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New Mac IIfx Recap?
Posted by: Uwguy2023 on 2024-05-27 15:50:07
Hi,

I have a brand new MacIIfx logic board. I assume I should recap this as well? Any suggestions or recommendations?

Thanks

Rick

IMG_3525.jpeg
Posted by: Unknown_K on 2024-05-27 15:54:05
If the machine doesn't want to shut down replace C24 and C9 which are the only leaky SMT capacitors on the board. The larger capacitors rarely if ever need changed and the tants will blow up if they need replaced (they short closed and pop generally not hurting anything in the process).
Posted by: jmacz on 2024-05-27 21:39:41
Is this a NOS board? Yeah, C9 and C24 should be replaced. Someone mentioned C1 blew in theirs and left a small crater. The original is spec’d to 16V but as recent info suggests with these tantalums, they need to be spec’d to double the voltage they will be used for. In this case I believe C1 is on 12V so instead of a 16V, you should replace it with a 25V rated one (47uf). I just replaced the axials too while I was at it.
Posted by: Uwguy2023 on 2024-05-27 22:51:41
Is this a NOS board? Yeah, C9 and C24 should be replaced. Someone mentioned C1 blew in theirs and left a small crater. The original is spec’d to 16V but as recent info suggests with these tantalums, they need to be spec’d to double the voltage they will be used for. In this case I believe C1 is on 12V so instead of a 16V, you should replace it with a 25V rated one (47uf). I just replaced the axials too while I was at it.
Thanks for letting me know.

Yes this NOS, a never used upgrade kit.
Posted by: pezter22 on 2024-05-29 16:59:48
Recapamac is the best resource for the vintage Mac capacitor info.

recapamac.com.au

Macintosh IIfx - Recap-a-Mac

The Macintosh IIfx is one of the rarer and more collectible Macs, so if you have one in your collection you should be...
recapamac.com.au recapamac.com.au
Posted by: EIMS on 2025-02-14 10:20:12
Is this a NOS board? Yeah, C9 and C24 should be replaced. Someone mentioned C1 blew in theirs and left a small crater. The original is spec’d to 16V but as recent info suggests with these tantalums, they need to be spec’d to double the voltage they will be used for. In this case I believe C1 is on 12V so instead of a 16V, you should replace it with a 25V rated one (47uf). I just replaced the axials too while I was at it.
Thanks for the tip about C1. I had a C1 blow, the original tantalum, fortunately just damage to the capacitor. I'll upgrade it to a 25V.
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