The CV1065 is an HF pentode with an MO base - thus a Mazda designed valve. Prior names for the CV1065 include the RAF VR65, the Army ARP36 and the GPO POVT200. The prototype was a modified SP41. The SP41 has a 4 Volt heater and the SP61 a 6.3 Volt heater.
The KB/K identifies this valve as being made to specification K1001 or K1006, the B denotes qualification by a UK authority and the K identifies the maker as ETEL, Electronic Tubes, High Wycombe.
The UK up arrow.
The The whole envelope is coated with zinc loaded screening paint.
The classic envelope is 32 mm in diameter, and excluding the MO base pins is 81 mm tall.
Reference: Data-sheet. Type CV1065 was first introduced in 1941. See also1941 adverts.
