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tempus fugit
 
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Default need help repairing old Heathkit weather computer

Hey all;

I'm working on repairing a Heath weather computer. Initially, none of the
funcitons really worked (temp, pressure, clock, etc.) I got it to the point
last night where everything was working except the clock, which kept time,
but I couldn't actually set it. So, I (stupidly?) poked around a little more
to try to get the clock going. I noticed a 4066 with some black stuff on the
pins, and some weird voltages around it, so I pulled it out, fired the unit
up, and checked the voltages again. They were still weird, but when I put it
back in and turned it on again, the pressure and temperature stayed at 0. I
was messing around with it again tonite, and the pressure and temperature
readings were more normal, but I noticed a couple of opamps (in different
locations) that were hot to the touch. There were no shorts in either of
them, and the voltages around them pretty much matched the schematic. I now
get bad readings in the temperature (-40) and pressure (0). I'm guessing the
opamps are at least part of the problem. Any idea why they are getting so
hot? Any other suggestions?

Thanks