Sensibly equivalent¶ to:
The TDD2A is a double diode triode for battery receivers. The function was as detector, AGC rectifier and first audio voltage amplifier in a superhet broadcast receiver.
See also TDD2A for a slimmer version of the envelope.
The reverse is plain paint.
The classic envelope is 44 mm in diameter, and excluding the B5 base pins is 106 mm tall.
References: Datasheet, 1040 & 1043. Type TDD2A was first introduced in 1934.
Absolute Maximum Operating Conditions¶
Thanks to Andy Cowley for supplying the above PDF datasheet.
Updated April 03, 2014. shape:classic construction:pinch type:double.diode.triode age:1930.1940 base:b5 heater:2.0v pins:5 pin:1.a pin:2.a(d1) pin:3.f(-) pin:4.f(+) pin:5.a(d2) pin:tc.g1