Does anybody know how much tolerance 74xx TTL chips have to a situation 
where on the LHS of the board near the V regulator is  5.13 volts while on 
the extreme RHS the voltage has dropped to 5.03 volts.  This is the new 
80386 board which draws a fair amount of current.  
See here:-
http://s100computers.com/My%20System%20Pages/80386%20Board/80386%20CPU%20Board.htm

I am using a 78H05 TO-2 regulator (Fairchild).   Even though these 
regulators are hard to find, with their heat sink they run nice and cool. 
Is the above acceptable both in terms of voltage gradient and absolute 
number i.e. >5V.

 While on TO-3 5V regulators, I have been plagued with "no name brands" 
that either quickly die or are way outside what they should be in terms of 
voltage.
Just yesterday I got 2 "LM323K's (5V, 3A) from Unicorn. One put 6.2 volts 
on a test board!!!!   I had others from Jameco that put out 4V's.

Since a couple of our recent S100 board use these regulars, please test 
them first. Mouser stopped carrying the LM323's. If anybody has a good 
source to name brand 78H05's or LM323's please let us know.
I'm reluctant to go with two L7805ACV's TO-220 (5V 1.5A) because they use 
up so much board space with their heat sinks.



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