PDP 11/45 partial success.

Ashley Carder wacarder at usit.net
Fri Mar 18 15:53:44 CST 2005


Mike Cesari said:
> If that fast spike looks like:
> 
>    5v _|___|____
>        |   |
>        |   |
> 
>    0v ________
> 
> ... or similar, this can (will) cause intermittent problems when you 
> load the system
> with usage like installation, compiles, etc. Especially when the spikes 
> bottom out at
> less than 2.5v. We saw this cause very "odd" system crashes on 11/70's. 
> Components on
> the h744 regulators started to degrade, `cause DEC pushed these to the 
> limit.
> We replaced the two output electrolytic caps, the output (power) 
> transistor, and the
> two disc caps that should be at the mate-n-lock that should go from 5v 
> to ground.
> (These are an ECO from the late `70's.)
> etc.....


What does ECO mean?

Ashley





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