Sensibly equivalent¶ to:
The VR102 (= M-OV Type BL63) is a low-impedance double triode with one grid taken to the top cap.
The VR102 was supplied by M-OV to the RAF during WWII. Thanks to Frank Whitby for confirming that the VR102 was used for the R1155 receiver that was fitted to Lancaster and other bombers. As part of the direction finding (DF) circuitry, it formed the visual meter switch operating at either 30 or 80 Hz. Its output fed the twin-needled Visual Indicator and one of these instruments was usually fitted on the top of the cockpit instrument panel.
A description of this clever circuit, designed by the Marconi Wireless & Telegraph Co. is given in the Manual for the R1155 (AP2548A Vol I Chapter 2). This can be seen on the Vintage and Military Amateur Radio Society's website.
The classic envelope is 42 mm in diameter and, excluding the IO base pins, is 113 mm tall.
References: 1040. Type VR102 was first introduced in 1939. See also 1939 adverts.
Absolute Maximum Operating Conditions¶
Updated January 05, 2022.