IBM 5155 Power supply schematics or info

[Jules Richardson]

On Wed, 2005-11-16 at 16:21 -0800, Chuck Guzis wrote:
> On 11/17/2005 at 12:43 AM Alberto Rubinelli - A2 Sistemi wrote:
> 
> >As soon as I touched the trimmer, I discover the problem !! The cursor was
> >instable !!
> 
> Congratulations!
> 
> One of life's hard-learned lessons:  On old equipment, pots, switches,
> sockets and connectors are not your friends.  

pots normally seem to be OK though *until you touch them*, as the wiper
still has good contact until it's moved onto a corroded spot. Personally
I've found it unusual to find one that's failed without even being
touched. 

(sockets and connectors seem much more prone to vibration or heat-
related movement, and of course switches always live with some of their
contacts exposed to corrosion anyway)

cheers

Jules