The 6CB6 is a sharp cut-off amplifier valve. The 6CB6 was designed for use as IF amplifiers at frequencies above 20 MHz.
The internal construction shows the two inner grids close to the flat cathode and with their wires straight and parallel to the anode. The anode is some distance away and is formed from two plates, one each side of the cathode. The beam plates are small formed sheets with rectangular holes in them.
Another view of the main construction
The anode is the dark metal and the beam plates are the brighter sheet behind.
The envelope is 17 mm in diameter and, excluding the B7G base pins, is 47 mm tall.
