Sensibly equivalent¶ to:
The EF86 is a low noise pentode intended for use as a RC coupled AF voltage amplifier, particularly in the early stages of high gain audio amplifiers, microphone pre-amplifiers and magnetic tape recorders. It replaced the EF37A and EF40. In use it is recommended that it is fitted into a vibration resistant base. This has a synthetic rubber mount.
The screen encloses all of the electrodes. The connecting wire from the base pins is copper. Additional screening can be seen below the lower mica.
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 EF86 was first introduced in 1953.
Absolute Maximum Operating Conditions¶
PDF scanned from an original document held by the museum
Updated April 10, 2016.