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ID = 17533
Tube type:  Reflex Klystron 
  Ca. 1925 up to 1945 extraordinarily rare. Production was less than 100 items. ****
Identical to CV87 = KRN2
Similar Tubes
Normally replaceable-slightly different:
Successor Tubes CV129   CV224  

Base Octal (Int.Octal, IO) K8A, USA 1935
Was used by Radar
Filament Vf 4 Volts / If 1.4 Ampere / Indirect

The first British klystron capable of operating as local oscillator in X-band radar receivers was developed by EMI in close collaboration with the Clarendon Laboratory. The approach was to scale-down the design of the already working S-band ‘Sutton tube’, using the same copper to glass seal technique to connect the external cavity. To prevent unacceptable dielectric losses in the glass wall, the klystron was designed to operate with the harmonic resonator proposed by Blumlein at EMI. The cavity was modified to operate in a three-quarter mode, with nodal circle in correspondence of the glass wall and an antinodal circle between the glass wall and the outer wall of the cavity.

According to Callick, early samples of KRN2 were available for experimentation by March 1941, followed by a production of about 100 units, many of which supplied to TRE for their X-band developmental sets.

Operated with 10 W in input at 1500 V and -425 V reflector, they gave about 100 mW in output over a range tunable from 3.05 to 3.45 cm. The klystron used a differential screw tuning mechanism. It was approved as CV87.

Dimensions (WHD)
incl. pins / tip
x 165 x mm / x 6.50 x inch
Information source Taschenbuch zum Röhren-Codex 1948/49   
-- Original-techn. papers.   Callick, Metres to Microwave

8fhb.png CV87: Manufacturer's Literature
Emilio Ciardiello

Just Qvigstad

Collection of



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