> Cool! An excellent idea, and with the interesting "glass-blower"
> approach is very interesting. So you modify the bulb to become a
> special purpose temp sensor? Does it matter if the bulb vacuum fails?

It does not matter if the vacuum fails since I do not intend to run the
bulb (electrically) hot. A tungsten filament is ok in air until it gets to
about 1200+ degrees C when it will burn up in the air oxygen (producing
white smoke).

> The larger resistance (10k+) wire wound resistors use a very fine
> nichrome wire and over 100'C they are quite usable for temp trip
> points and some low res temp measuring.

Roman, Nichrome, Constantan and other heater and resistor wires are
specially formulated for low tempco. You are better off using the
unadultered metal. Like Iron, Copper, Aluminium, Tungsten, Platinum, you
get it. The bare metal always has a higher temp. coefficient than the
alloys formulated for low tempco. A simple copper coil (high temp, rated
miniature choke etc) will work better probably. Also beyond a certain
degree of heat there are other choices (like molten salts and conducting
glass ;-). These have rare applications however. FYI molten glass is not
so bad a conductor, under the circumstances.

Peter

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