The Nixie tube is a cold cathode display for displaying
numerals using glow discharge. The glass tube contains a wire-mesh anode and
multiple cathodes, shaped like numerals or other symbols.
Applying power to one
cathode surrounds it with an orange glow discharge. The tube is filled with a mainly
neon gas and often a little mercury or argon, in a Penning mixture. Although it
resembles a vacuum tube in appearance, its operation does not depend on
thermionic emission of electrons from a heated cathode. It is therefore called
a cold-cathode tube.
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| A GN-4 nixie tube |
I recently found a rather nice wooden boxed H. Tinsley & Co. Ltd Mirror Galvanometer, the calibration certificate inside is dated 1959.
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| Calibration certificate dated 1959 |
I purchased
a Nixie
FunKlock Kit from PV Electronics. To make this
into a thermometer the kit needed some modifications, I added a Dallas DS18B20 temperature
sensor which is what is used to sense the temperature and then display this on
the Nixie tubes.
Assembling the kit..
Success! the kit works.
Now I had a working board, the next stage was to figure out how to mount the kit inside the Galvanometer case. I didn't want any screws showing so I made some brackets from aluminium bar to support the PCB.
The boards have been fixed in place so that the Nixie tubes protrude out of front of the case through the cut out where the original scale sat.
Here I have used XLR connectors for the power input and temperature sensor connection.
