On Sat, 30 Nov 2002, Wagner Lipnharski wrote:

*>I canceled the previous order of thermocouple thermometer and ordered a non
*>contact infrared unit, so I can measure the temperature right over the
*>boards inside the oven, locate the most uniform temperature spot and
*>calibrate the controller.  I just hope the non contact thermometer will not
*>be tricked by the oven door glass temperature (lower than the boards
*>inside).

It is not the glass temperature, but its lacking transmission at those
wavelengths that is going to get you.

*>Will tie the 1N4148 sensors directly to the grill tray metal, so probably
*>will be measuring the same temperature from the boards.

Maybe lose the diodes and use a honest rtd ? The diodes will drift and go
bad when exposed to high temperatures over some time so your calibration
will soon be off.

Peter

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