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From: ericmcg@pro-generic.cts.com (Eric Mcgillicuddy)
Newsgroups: comp.sys.apple
Subject: Re: Western Design Center (was Re: 6V power)
Message-ID: <9045.infoapple.net@pro-generic>
Date: 26 Dec 89 05:33:12 GMT
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In-Reply-To: message from brianw@microsoft.UUCP

In my original post, I mentioned that the 65816 have the traces to the 5V
supply bypassed to prevent diffiulties with the other chips. I have thoroughly
discarded the resistor divider idea. It was quick and dirty, but not the best
solution. Several solutions are possible a 6..2V Zener is one, a 6V regulator
is another. Choose what you can work with. I assume that the people using this
idea are not electrical engineers so I attempted to keep it simple. Oh well.

The power for the entire card comes from the slot, it is poor practice to draw
power for a card from the motherboard. I would not buy a product that did and
I'm sure the AE people would not design it that way. As for hacking the
hardware to work, I would suggest that you limit yourself to 10MHz. The
designer probably built the board for 10.5MHz and de-rated it to 7MHz. This is
the rule of thumb for most designs, by reputable companies at least. The other
components can thus withstand the increased speed and power dissipation. I
would strongly reccommend not trying to push it to 13MHz, the professionals
who did took precautions. You might get away with it, but I don't recall any
statements as to the failure rate of these accelerators, might be as low as a
few minutes. 

With the TWII released, does anyone know it a TWGSII is coming soon. It might
be useful to wait for the real thing.