The twelve pin base of the Compactron.
The idea of putting two valves in the same envelope has been widely employed in the past, but recently the General Electric Company of America have considerably extended the idea by including up to four valves in the same glass envelope. These valves will, for obvious reasons, be know as 'compactrons'.
The first two valves of the series are mainly intended for use in domestic superhets, although may other uses will certainly be found for them. These two valves will enable the ordinary 'four plus one' superhet circuit to be constructed using only two valves - the power rectifier being incorporated in one of the valves! The first of the valves will be used as a converter and IF amplifier; it contains two sections which are roughly equivalent to a 12BE6 and a 12BA6 in the same envelope. The second valve will be used as a detector (diode), audio amplifier (high μ triode), power output (tetrode) and HT rectifier.
The valves will be of a similar design to the present miniature types, but will have bulbs of somewhat larger diameter in order to accommodate the various sections. The height is expected to vary between about 1 in. and 2.75 in., according to type. A special 12 pin base (B12C) is used in order to provide the necessary number of connections to the various sections of the valve. The pins are in a 0.75 in diameter circle protruding from a glass base of about 1.125 in diameter.
At the moment the valves are being developed mainly for domestic radio and television equipment, but the manufacturers are making plans for designing and producing up to about a hundred types of compactrons for all kinds of uses. It is expected that the price of each compactron will be about twenty per cent lower than the total price of the conventional valves which it can replace.
On Junkbox are two lists of GE Compactrons, One from June 1962 and the other from Spring 1964.