Sensibly equivalent¶ to:
The E2047 is an experimental valve from M-OV and this one carries the serial number 44. On the outside of the box this exhibit came in was written in pen W107 and the heater rating matches this as does the pin connections.
Our other E2047 has W77 etched into the glass but the heater ran at 12.6 Volts not 6.3. The pin connections for the W77 and the W107 are the same suggesting that the W107 was a development of the W77 with a 12.6 heater.
The The bright anode with wire grids within.
The thin glass tube envelope is 18 mm in diameter and excluding the B7G base pins, is 46 mm long.
References: Datasheet & Observation.
Absolute Maximum Operating Conditions¶
Updated September 11, 2013. shape:thin.glass.tube construction:all.glass type:pentode age:1940.1950 base:b7g heater:6.3v pins:7 pin:1.g1 pin:2.k pin:3.h pin:4.h pin:5.a pin:6.g3 pin:7.g2