The 6J4 was the prototype for the CV1763. It is a miniature grounded grid triode with a 2.5 Watt anode dissipation for operation into the UHF at 550 MHz.
The anode is a pair of flat based U sections that are joined by bright straps. The grid is a close pitch but not a frame grid.
The Sylvania name in green paint.
The thin glass tube envelope is 18 mm in diameter and, excluding the B7G base pins, is 47 mm tall.
Reference: Data-sheet. Type 6J4 was first introduced in 1950. See also1950 adverts.
