The CV2209 is a miniature HF pentode. Typical operating conditions are found in the attached data-sheet.
The prototype was the Mazda designed CV1116 that was fitted with an MO base cap.
The KB/F identifies this valve as being made to specification K1001 or K1006, the B denotes qualification by a UK authority and the F identifies the maker as STC, Paignton.
The two small plates of the anode are joined by an integral strap. The screen grid is has a fine pitch and this allows g3 to act as a second control grid if required.
The STC logo and the commercial Type designation of 6F33.
The thin glass tube envelope is 18 mm diameter and excluding the B7G base pins, is 45 mm tall.
Reference: Data-sheet. Type CV2209 was first introduced in 1952. See also1952 adverts.
