The PC900 is a miniature VHF amplifier triode for use as an RF amplifier in television receivers. It is low impedance and has a high mutual conductance. This is partly achieved by a very low cathode to grid spacing. The anode is made of two rectangular channels, one either side of the cathode. The beam plates form the electrons into two beams.
The grid is wound on strips rather than rods and it looks as if the strips are welded to the horizontal bar. This would indicate a frame grid where the very thin wire has been wound at 50% of the breaking strain. This would stretch the wire and keep each strand flat. This allows the very small gap between cathode and grid.
The anode is shaped so that only a small section faces the control grid. The rest is heat sinking.
The thin glass tube envelope is 18 mm in diameter and, excluding the B7G base pins, is 34 mm tall.
References: Data-sheet, 3002 & 1040. Type PC900 was first introduced in 1963. See also1963 adverts.
