The 3B/240M is a small VHF transmitting triode. The drive required for full output is 2.5 Watts and the maximum grid current is 35 mA. This suggests the design use is class C and so would be used for AM and CW transmitters.
The side view reveals the two independent anode fin arrangements with the cathode assembly in the centre.
A closer view of the central electrodes. The grid is wound on copper supports and passes across the flat coated cathode.
The use of multiple grid and cathode connections is to reduce capacitances and thus achieve the 200 MHz frequency.
The wide glass tube envelope is 27 mm in diameter and, excluding the B8B base pins, is 62 mm tall.
