Designed as general purpose triodes, two independent valves exist in the ECC82 envelope. A special quality version was also produced, the E82CC. Designed for differential amplifiers in industrial equipment, the anti microphonic and matched pair version E182CC was also made.
An amplification factor of 17 is quoted, and the ECC82 is virtually a pair of EC90 triodes in a single envelope but not designed for RF use.
The yellow lettering dates from 1969 - the 50th anniversary of the founding of Mullard.
Each triode can dissipate 2.5 Watts.
The anodes are stitched together and tabs passing through the mica discs hold them in place.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A base pins, is 48 mm tall.
References: Data-sheet & 1040. Type ECC82 was first introduced in 1951.