Sensibly equivalent¶ to:
The 2E26 is a small VHF transmitting beam tetrode that was typically used in mobile transmitters. As a single ended Class C RF amplifier it would generate up to 5.5 Watts in the VHF range to 125 MHz. If used in push-pull with up to 500 volts on the anodes the pair could produce up to 50 Watts but 27 would be more typical. The maximum dissipations of 10 Watts anode and 2.5 Watts for the screen had to be observed and so it is probably that they would have been used for telephony rather than CW.
As with other transmitting valves the design allowed them to be used as AF modulators as well. For AM modulation the 2E26 would be used as either class AB1 push-pull or single ended for low powers. With this dual use the transmitter would need fewer valve types as spares. This was particularly required in mobile communications.
The box anode is surmounted by the top mica. Above the mica the grid cooling fins can be seen.
The wide glass tube envelope is 28 mm in diameter, and excluding the IO base pins is 76 mm tall.
References: Datasheet & 4038. Type 2E26 was first introduced in 1947.
Absolute Maximum Operating Conditions¶
Updated February 21, 2014.