The VR56 is a pre-WWII military receiving pentode valve. The VR prefix in the type designation stands for Valve Receiving. This exhibit was made in Canada by Rogers and also has the old stores code of 10E/11402 printed on the screening paint.
The valve in civilian name is an EF36. This valve was obsolete by the 1960s, and our data sheets show that the EF36 had identical characteristics and pin connections to the EF37 and EF37A. These were all high gain low current intermediate frequency amplifiers in superhet receivers and all featured external metalisation. With their low capacitances they would be useful at radio frequencies as well as IF.
The Rogers name and logo.
The A M and Crown for the Uk Air ministry.
The wide glass tube envelope is 29 mm in diameter and, excluding the IO base pins, is 82 mm tall.