1636

RCA 1636 beam deflection mixer.

The valve measures 118mm from top connector to base, 33mm across the glass, and an extra 12mm for the side connectors. It has an octal base.

This valve was used as a balanced mixer for 600MHz. It was used in the AN/TPS-3 radar.

The metal cylinder inside the valve is marked with E (or three horizontal bars) and 286.

Heater voltage	6.3V
Heater current	300mA
Max grid to anode voltage (G2, 3, 4)	300V
Max dynode voltage	250V
Max deflecting electrode voltage	150V
Max grid-anode dissipation	3W
Typical operation
Grid-anode voltage	30V
Dynode voltage	240V
Deflecting electrode voltage	140V +/-15V
Deflecting electrode centering voltage	-5 to +5 V
Cathode shield (G1)	0V
Deflecting electrode voltage for operation on oscillator fundamental frequency	1V max

The operation of the valve depends on the movement of an electron beam across narrow apertures. A well defined rectangular electron beam is focussed on a barrier, and deflected across two narrow apertures by a signal voltage and a local oscillator voltage applied to the deflector electrodes. It also incorporates a single stage of secondary-emission multiplication.

Pin	Function
1	Heater
2, 4, 6	G2, 3 and 4
3	n/c
5	G1
7	Cathode
8	Heater
Side contacts	Deflecting electrodes
TC	Dynode

The construction consists of a cathode, a cathode shield (g1), and a combined grid-anode (g2, 3 and 4) assembly. G2 and 3 are apertures, followed by the deflecting electrodes, and finally G4 which has a barrier aligned with the apertures of g2 and 3 which stops the electron beam. Two apertures either side of this barrier allow the beam to reach the dynode when deflected to pass through them.

Thanks to John Walker for providing data on this valve

This file was last modified 15:35:43, Saturday November 12, 2011