Sensibly equivalent¶ to:
The Ever Ready K30K is a directly heated triode and identical to the Mullard PM2HL - Mullard being the actual manufacturer. This example of the balloon enveloped version is metalised whereas K30K has a plain glass bulb.
The identification is printed on to the dome.
The balloon envelope is 41 mm in diameter and, excluding the B4 base pins, is 79 mm tall.
References: Datasheet & 1043. Type K30K was first introduced in 1937.
Absolute Maximum Operating Conditions¶
Thanks to Andy Cowley for supplying the above PDF datasheet.
Updated January 09, 2017. shape:balloon construction:pinch type:triode age:1930.1940 base:b4 heater:2.0v pins:4 pin:1.a pin:2.g1 pin:3.f pin:4.f