Sensibly equivalent¶ to:
The type 77 is a general purpose pentode voltage amplifier/detector. As a high impedance device the control grid is taken to the top cap for maximum isolation from the anode circuit.
The Type 77 is a sharp cut-off pentode similar to 6J7G.
The outer screen connects to a pressed plate and the top opening is small - just sufficient for the top cap connection to the control grid supports.
The classic envelope is 39 mm in diameter, and excluding the UX6 base pins is 98 mm tall.
References: Datasheet & 4059. Type 77 was first introduced in 1932.
Absolute Maximum Operating Conditions¶
Updated January 11, 2017. shape:classic construction:pinch type:pentode age:1930.1940 base:ux6 heater:6.3v pins:6 pin:1.h pin:2.a pin:3.g2 pin:4.g3 pin:5.k pin:6.h pin:tc.g1