The DEH612 is a dull emitter triode with a Thoriated Tungsten filament designed for six Volt use in battery receivers. It is described as a general purpose valve and the design dates from 1927 or 1928. The presence of the BBC stamp suggests that this is a 1927 valve as the use of the stamp had ended by 1928. On this BBC stamp are the words Entirely British Manufacture
The balloon envelope is 56 mm in diameter and, excluding the B4 base pins, is 93 mm tall.
Reference: 1043. Type DEH612 was first introduced in 1927.
Absolute Maximum Operating Conditions¶
Updated April 11, 2013.