H7861 PSU issues

Aaron Jackson aaron at aaronsplace.co.uk
Thu Nov 2 09:22:42 CDT 2017

Thanks! It was very satisfying and not the worst thing to go wrong
for a beginner. 

I was also quite surprised that such a simple component would die,
and what I find more confusing is that it died while I was using
the machine.


Noel Chiappa via cctalk <cctalk at classiccmp.org> wrote:

>     > From: Aaron Jackson
>     > Picked up a few 555s and sockets and now it works!
> Congratulations!
> It's odd that a 555 failed, but sometimes there's no rhyme or reason to what
> fails. E.g. I was fixing some broken M7859's (KY11-LB Programmer's Console),
> and on one of them a 7493 (4-bit counter) had died. That's not one of the
> 'problem' 74xx chips, like ISTR the 7474 being?
> 	Noel

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