Re: RE: Techtoolslist Digest, Vol 6, Issue 2

From: Rodger Boots <rlboots_at_cedar-rapids.net>
Date: Sun Apr 03 2005 - 00:42:29 EST

<x-flowed>You didn't use the wrong family by any chance? 74C has the worst output
drive followed by 74LS. 74HC has good pullup. And don't just look at
the chip you replaced, also check the other chips that that one drives.

OR, add a pullup resistor. Others have suggested 1 K, but 4.7 K would
probably be a better choice (you get the value too low, expecially if
driving a lot of inputs, and you can affect the low-state voltage).

Robert C. Bullock wrote:

>No, new chip. Replaced a lot of the chips in the timeing circuit and
>socketed them with double wipe sockets.
>
>
>-----Original Message-----
>The legs of the chip in question aren't rusty by any chance are they?
>
>Just a thought :)
>
>Martin.
>
>On Saturday 02 April 2005 16:00, Robert C. Bullock wrote:
>
>
>>I have a Pac with a low 6M* line, when I piggyback a 74LS86 (IIRC, *****
>>
>>
>
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>
>
>
>

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</x-flowed>
Received on Sun Apr 03 10:12:41 2005

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