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CV2381 / N1034A backward wave oscillator

This valve measures 260x125mm overall and has a 7 pin base

This is an S-band backward wave oscillator.

Nominal heater voltage (a)6.3V
Max heater current2.6A
Max surge heater current4.0A
Min delay line voltage (b)150V
Max delay line voltage (b)1.17kV
Max delay line current (c)50mA
Max delay line dissipation60W
Max anode voltage200V
Max anode current30mA
Max negative grid voltage (d)-100V
Min power output20mW
Min total tuning range (g)2400 to 4500MHz

The output terminal and metalwork are intended to be operated at earth potential.

(a) The heater voltage shall be applied at least two minutes before the HT voltages are applied
(b) The delay line voltage must always be applied before the anode voltage
(c) The delay line and collector are connected internally so 'delay line current' includes collector current
(d) For normal operation the grid is set at zero volts. Oscillations are cut off at Vg=100
(e) The magnetic field required to focus the electron beam is provided by a permanent magnet. External magnetic fields or ferro-magnetic objects might distort the focussing field and cause issues such as noise and modulation. Magnets or ferrous objects should be kept at least 8 inches away; 18 inches if low noise output is required.
(f) The temperature at any point on the external surface should not exceed 200°C. Minimum air flow directed onto the radiating fins and side of the valve should be 20 cubic feet per minute
(g) The valve is tuned by varying the delay line voltage. 150V gives 2400MHz and 1170V gives 4500MHz.
(h) The base is rigidly attached to the metal shell. The pins must be connected by flexible leads
5Delay line and collector
6Delay line and collector

CV2381 / N1034A
Quarter view Quarter view