The CV5900 is a reflex klystron oscillator that operates between 6.5 - 7.7 GHz. The main electron path is between cathode and resonator. The electrons are directed back by the negative charge on the reflector - op to 400 Volts.
At the centre frequency of 7 GHz the minimum output is 85 mW. The power drops when tuned away from the centre frequency but is always above 50 mW. The mechanical adjustment of frequency is achieved by changing the geometry of the internal cavity. The flexible top can be minutely moved by the adjustment bellows. Electrical tuning is limited to 25 MHz around the set mechanical frequency. This electrical adjustment allows for some automatic frequency control.
These reflex klystrons would be used as the local oscillator in the front end of a Radar superhet receiver. The receiver needs to have an adjustable frequency response as the magnetron in the transmitter would be fixed in frequency.
This valve came within a polythene box where the lid has an internal ring that fits within the base.
The soft plastic cross pieces hold the valve firmly in the centre. The output probe is 31 mm in length and replaces pin four of the International Octal base.
Seen face-on, the adjusting mechanism sits in one of the side spaces.
The reflector at the top cap and the output probe at the bottom.
The reflector or repeller.
The output probe would pass into waveguide with the modified valve-holder being supported on fixing spacers.
The thin metal tube envelope is 26 mm in diameter and, excluding the IO base pins, is 56 mm tall.