ID:
2337
Maker's Name:
Edwards High Vacuum Ltd
Where made:
England
Dimensions:
27 × 16 × 7 cm
This consists of a heated filament which is cooled mainly by convection. This affects the temperature of the filament, and therefore the electrical resistance of the filament.
The filament forms part of a Wheatstone bride for determining the resistance, which is a measure of the vacuum in the gauge.
This gauge must be calibrated against a known vacuum using eg a McLeod gauge.
The gauge must be separately calibrated for different gases. Hydrogen removes heat rapidly, and the noble gases slowly.
This gauge is only suited to low vacuums.
