>this was built in 1980 and didn't have a PIC in it.  
>The logic was just a comparator,

It fair takes me back, (puffs slowly on pipe..)
just proves that more complex isn't 'Always'
better,it's pointless switching something with the 
responses of a heater on and off at a zillion 
times a second; a jet fighter's controls,
now thats different!Theres a very apt saying 
here in England 'handsome is as handsome does'
in other words don't use a racehorse to pull a plough.
why not use a plug in timer socket; they're cheap
and safe...
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