Re: Just another power supply conversion.

["Michael J. Mahon" <mjmahon@aol.com>]

Lukazi wrote:
> Hi all,
>
> I've just gone through a IIGS power supply conversion. New quad
> voltage supply that fits into a IIGS power supply case. Details are up
> on my blog if you are interested.
>
> http://lukazi.blogspot.com/2011/06/power-supply-conversion.html
>
> Ta.

You did a nice conversion.  I hope it gives you great service.

On your blog, you expressed concern about the essential reliability
of an old Apple supply (implicitly, in comparison with a new one).

I believe that empirical evidence will confirm that, with the
exception of electrolytic capacitors, which have an unavoidable
failure rate with time, and the line bypass capacitor, which can
be killed by large line transients, the rest of the Apple supply
is just as reliable as the day it was made.  (Perhaps even better,
since the "infant mortality" part of the failure curve is past.)

The "wearout" part of the bathtub curve is quite distant for the
non-electrolytic components of the power supply--just as it is
apparently quite distant for the computer itself.

BTW, most 120vac switching supplies can be converted to 220vac
by changing one connection (converting a half-wave voltage
doubler to a half-wave rectifier).

-michael

NadaNet 3.1 for Apple II parallel computing!
Home page:  http://home.comcast.net/~mjmahon/

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