This exhibit was last updated on 03 December 2012
The VCR522 is the smallest of the WWII cathode ray tubes. The display is one inch diameter. The tube will operate with about 1000 Volts across it and the deflection is electrostatic. Like all WWII UK CRT's the heater is 4.0 V at 1.0 A. The heater cathode insulation is poor and the heater must be floating or strapped to the cathode.
The RADAR indicators that employed it displayed a horizontal line that had vertical blips to denote the origin and the reflection. The distance between the two was a measure of the distance. Our specimen came in a military style rugged metal tube, had rubber spacers to keep the glass from hitting the metal and a paxolin base with nine sprung sockets. The tube has a horizontal line burnt into the phosphor. The display is probably green.
The end window envelope is 36 mm in diameter and, excluding the base pins, is 143 mm long tall.
References: Radio Constructor article.