Sensibly equivalent¶ to:
Ever Ready made valves in the early days only, so this DAF91 was made for them. The DAF91 is a diode pentode valve was designed for battery portable radio receivers. This short grid base pentode was designed with particular reference to AF voltage amplification. The 1.4 Volt filament is to be run from a dry cell and the 90 Volt anode rating matches standard HT batteries.
The device was specified for use as a detector and first audio amplifier.
With a variation in lighting the lettering appears clearer.
The thin glass tube envelope measures 17 mm in diameter and the excluding the B7G base pins, is 45 mm tall.
References: Datasheet, 3002 & 1040. Type DAF91 was first introduced in 1946.
Absolute Maximum Operating Conditions¶
Updated February 05, 2013.