This thermocouple (described in literature as a thermojunction) is designed to be built into the walls of coaxial lines and waveguides. Referring to the main photo the junction is in the upper section above the copper disk. There is a small bypass capacitor built in below the disk so the device is open circuit at d.c. but will pass RF. The junction and support structure forms a loop which is substantially aperiodic at frequencies up to 6GHz.
The device itself has a resistance of about 20 ohms and gives an e.m.f. of about 12mV for a current of 10mA. The copper disk is notched to provide location of the plane of the loop with respect to the circuit. The end cap is positive to the disk.
The device carries the serial number 7629 on the glass.
Donated by Martin Byford
This file was last modified
15:10:40, Tuesday September 02, 2014