Re: Apple IIe power supply

[mjmahon@aol.com (Michael J. Mahon)]

Eric asked:

>I am trying to fix a broken power supply. Everytime I put in a new fuse, it
>blew when i turned on the power. Even tried increased from 1Amp to 2Amp
>fuse, still blew it. Suspected a short circuit somewhere.

You would have been wise to suspect this as soon as the first
replacement fuse blew.

>I read the FAQ, there's a common problem with the capacitor. However, is
>this a symptom to change the capacitor?

Not necessarily.  Electrolytics are not the most common cause of shorts.

It may be as simple as replacing the bridge rectifier if it was damaged
by, say, a nearby lightning strike.  But, most likely, the switching power
transistor is shorted--which will often cause some other components to
go south, or its failure may have been caused by another failure.

If the switching transistor is shorted, the easiest course is probably
to replace the supply, since it's unlikely that it will be the only problem
(especially after you've popped a couple more fuses).  ;-(

-michael

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