-=> Roy J. Tellason said to Greg Mayman
 -=> about "UNKNOWN IC" on 08-26-04  12:06.....

 RJT> And that implies software,  and that the chip has some code in it...

Almost certainly these days.

CHANGING THE SUBJECT....

Does anyone have a circuit of a deep freeze failure alarm? I
recently had to empty about $60 worth of stuff into the garbage
when we found the power plug on the freezer had been bumped and
the thing wasn't working.

An alarm that went off before the stuff thawed out would have
saved it all.

I thought I remembered seeing such a gadget as a project in one
of our electronics magazines some years ago, but I can't find it
in any of the copies I've saved.

I have some ideas of my own, but I thought I'd toss the matter
into the ring to see whether anyone has already got something.

The requirements are:

1. Battery powered

2. Alarm to go off if temperature rises above a preset limit.

3. Preset limit to be adjustable between 0 deg C (32 F) and -20 C
   (-4 F) or thereabouts.

4. Long battery life in the non-alarmed condition.

5. Alarm to be able to operate for several hours without draining
   the battery, in case the house is unattended when the alarm
   goes off. Alarm must be very low drain or operate in short
   beeps.

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

... To keep milk from turning sour: Keep it in the cow.
___ Blue Wave/386 v2.30

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