Apple IIe Power Supply popped and now dead

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Apple IIe Power Supply popped and now dead

Hi all,

My Apple IIe power supply just popped and died. I've opened it up and I see what looks like a capacitor or something which is labled: "0,1uF@X" has a buldge in it. There is also this dried carmel coated stuff on some of the other componets what that? 

 

Can this component be purcahsed and removeded and resoldered? I cant see anything else dmaangd.

 

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Those X2 caps (commonly

Those X2 caps (commonly referred to as "RIFA caps" because RIFA was the brand normally used in Astec and Dynacomp powersupplies used by Apple) blow frequently.  Unfortunately when they do they often pop the fuse and/or other components.  I'd start by replacing all of those large caps like that one and the fust if necessary.  If that doesn't do it then you'll need to start troubleshooting from there.

 

And yes, you can easily remove those and purchase replacements.  I bought some through Aliexpress, but places like Mouser, Digikey, JDR, etc, should also have them.

 

 

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ok thanks. I've got a local

ok thanks. I've got a local electronics shop what should I ask for? 

 

Also the mainboard that was connected to this power supply when it blu now does not boot up. The "POWER ON" led flashes and when tested with a working powersupply the power supply makes a soft cherping sound and only flashers the POWER ON LED. I've visual inspected the mainboard and can't see anything burnt out. Where should I start?

 

BTW: here is a photo of the power supply. The big thing in the middle that looks like it coated in caremel is that blowen? Or did it have some protective layer? it looks different to the blown "capacitor carmel" as its not sprayed on the mainboard its only on the actual component. And also the component to its left.

 

 

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Time to Troubleshoot

The chirping and flashing power light is generally the sign of a short circuit. The power supply is essentially starting up/shutting down/starting up/shutting down...

 

Something must have shorted when the X2 cap died. You will need to troubleshoot the board by hand using a multimeter (in continuity mode) looking for a short circuit and replace any bad components. If you are not into electronic repairs, you may need to inlist the help of someone with experience in this area.

 

Make sure you remove all cards from the expansion slots when testing to confirm whether it is the motherboard or an expansion card that has the short circuit. If after removing all expansion cards you are still getting the chirping, you know for sure that something on the motherboard has shorted. If after removing all expansion cards the problem goes away, try reinserting the cards one at a time until the chirping returns and you will have identified the offending card which will need repair.

 

The foul smelling brown goo is what is released from the X2 capacitors when they explode. You are lucky as I have had these X2 capacitors blow twice (in separate //e's) and in both cases they sprayed that brown foul smelling goo throughout the PSU case which required significant cleaning to try and get rid of the odour. The first time it happened the smoke could be smelt in my house for days! :-)

 

Cheers,

Mike

 

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Yes the components in the

Yes the components in the middle "coated in caramel" should look like that.

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Thanks for the reply. I'll

Thanks for the reply. I'll have to get myself a multimeter and read up on the testing process. Should I change any other capacitors while I have it open? 

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I would probably not

I would probably not arbitrarily replace other caps unless they show signs of leakage, swelling or they show a dead short when you meter them.

 

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