be sure to merge the link if it is on two or more lines.
Or go to eBay and search under AN/FMQ-13(V)
Five have been sold; two remain.
Aha, it's a "The Amateur Scientist" column, "Measuring the Wind with Hot Metal" by Shawn Carlson. A CD of all the Amateur Scientist columns is available at (click the $29 link at the bottom of the page).
It may be easier to change the circuitry to operate on 3.3V, as there's very little to it. The circuitry appears to be a heater (resistor) driven by a 7805 (not needed with a well-regulated 3.3V source, just lower the resistor to give the same heat at 3.3V as the one shown gives at 5V) and an op-amp (there are 3.3V ones meant to run on 'digital' power for modern computers, cellphones and such) to amplify the difference voltage between two thermocouples. Voltage is read by a DMM.
I think that is a good idea. And I think you should use a fresh bulb, because once used, the wire get brittle. /Sven W
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