Bob Blick wrote:
> Marcel duchamp wrote:
>> I'm going to test mine in a more dynamic environment and see how long it 
>> lasts.  I made a large (12 inch diameter) analog meter out of it.  A 
>> PIC16F88 compares the feedback pot on the motor to a thermocouple signal 
>> and provides a nice large temperature gauge.
> 
> Potentiometers can last a long time under the right conditions. You 
> should lubricate it. This thermometer I designed uses a 1/4 scale hobby 
> servo geared up using toothed belt and sprocket so it can swing 270 
> degrees. The first servo lasted 2 years, the second one has been in 
> about four years. Here's a look at it:
> 
> http://bobblick.com/wnw_thermo.jpg
> 
> Cheerful regards,
> 
> Bob

That's pretty cool Bob! Is it in Mendocino?

Hobby servos was a fallback plan; which type did you use?  The motor-pot 
setup might last a long time; I don't know yet.  I just imagined that it 
might wear out the pot element sawing back and forth... depends on the 
signal conditions and so on of course.  Monitoring environmental ambient 
conditions could be heavily filtered so you can avoid jitter.  I can 
probably add some hysteresis to mine - it's going to be monitoring kilns 
in ceramic studios and maybe hot glass shops.

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