Summary

Beam Tetrode used as the output valve in radios in the 1940s and 1950s. This valve was the most common type used in domestic radios in that period but it was also widely used in amplifiers, transmitters and instruments. It is still manufactured for the audiophile and guitar amplifier market.
Australian made Mullard branded tubes were normally manufactured by Philips. The excise mark (½) indicates that this was the case for this valve.
Manufacturer: Philips Electrical Ltd., Hendon, South Australia.
6.3 V indirectly heated cathode.

Physical Description

Tubular bulb on seven pin octal base

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