The CV67 type of klystron was used in early 10 cm radar systems as a local oscillator. This exhibit looks like a post-War replacement for one of the classic WWII reflex klystron oscillators (Sutton tubes) such as the CV35, CV36 and CV67. All were basically similar but tunable over slightly different frequency ranges. The WWII originals, dating from late 1941, had a screw terminal at the top. Later replacements had the neat top cap as seen in the photograph.
Although not marked as such it is believed that this is a CV67. The actual markings read 0341 and this may be a serial number.
These klystrons were used to provide a continuous Local Oscillator (LO) signal at the correct frequency for the particular radar so that this remained available to the radar receiver between transmitter pulses when the magnetron was silent. Typical LO power output was only 300 mW at 'S' band (approx. 3 GHz) but this was sufficient to mix with the (very weak) radar echoes in a superhet-type receiver. In early radars the tuning of the magnetron transmitter was not adjustable so the klystron had to be 'tweaked' until the LO frequency matched that of the magnetron.
The wide glass tube envelope is 30 mm in diameter and, excluding the IO base pins, is 160 mm long. The metal work is 52 mm in diameter.
References: Data-sheet & Private communication. Type CV67 was first introduced in 1941. See also 1941 adverts.
Absolute Maximum Operating Conditions¶
Updated January 08, 2022.