Re: Making defender power supply adjustable

From: John Robertson <>
Date: Wed Sep 21 2011 - 01:58:46 EDT

Neil Bradley wrote:
>> I disagree.
>> A rebuilt Williams Power Supply is way better than a switching on. :)
> Please explain. I'm honestly curious how a linear regulated supply is
> better than a switcher.
> -->Neil
> ----------------------------------------------------------------------------
> C. Neil Bradley - Excessive process falsely elevates the incapable and
> ties
> the hands of the exceptional.

Mostly it is the way the reset is handled on the Williams video games.
They prefer the ramp up to +12, rather than the instant on. So my
experience is that the boards start better with a good working linear
supply than the switchers.

The risk for the linears is if the pass transistor shorts out...the cure
for that is the Williams Reset Protection PCB that goes between the
linear supply and cabinet harness to PCBs.

John :-#)#

John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 
Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, VideoGames)
"Old pinballers never die, they just flip out"
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Received on Wed Sep 21 01:58:51 2011

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