-=> Roy J. Tellason said to Greg Mayman
 -=> about "UNKNOWN IC" on 09-01-04  12:09.....

 GM> 1. Battery powered

 RJT> I'd use a 9v alkaline -- they have a pretty good shelf life (several
 RJT> years) at this point.

Yes, alkaline is the only way to go for something like that.

 RJT> Use a thermistor and a resistor to bias one input of a comparator, 

Some thermistors are quite high resistance, so the battery drain
would be low. It could be kept even lower by pulsing the circuit
briefly, say for 1 second every five minutes or so.

   ,-./\
  /     \ From Greg Mayman, in beautiful Adelaide, South Australia
  \_,-*_/    "Queen City of The South"    34:55 S  138:36 E
       v

... "640K ought to be enough for anybody." - Bill Gates, 1981
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