The CV95 is a bolometer element. When mounted in a suitable cavity it would be used to measure microwave power. It operates by changing resistance as it changes temperature, and the incident energy from the microwaves would cause it to heat up. Bolometers are very delicate and can easily burn out if subjected to excess power.

The measuring instrument would probably have used a Whetstone bridge with a calibrated variable resistance in the other arm. The variable resistance would have been altered so that a null was produced across the mid point of the bridge.

The thin glass tube envelope is 10 mm in diameter and, excluding the base pins, is 22 mm tall.

This exhibit was last updated on 19 January 2003