Sensibly equivalent¶ to:
The IW3 is a full wave rectifier from the early days of mains radios with the 4.0 Volt heater that was standard at the time. With a current rating of 120 mA at 350 Volts this would have powered a substantial piece of equipment.
The picture shows the top view of the envelope. The heater rating is clearly shown.
The balloon envelope is 52 mm in diameter and, excluding the B4 base pins, is 105 mm tall.
References: 4023 & 1043. Type IW3 was first introduced in 1933.
Absolute Maximum Operating Conditions¶
Updated January 04, 2013. shape:balloon construction:pinch type:rectifier.fw age:1930.1940 base:b4 heater:4.0v pins:4 pin:1.a(1) pin:2.a(2) pin:3.h.k pin:4.h