The C70D is a mystery. It is probably a screened grid tetrode or a pentode and was probably designed for broadcast radio receivers in the 1930s.

Ever Ready is best remembered for the manufacture of radio batteries but also made and sold radio receivers. They were never a valve manufacturer, but purchased their valves exclusively from Mullard and sold them for use in their own sets.

The classic envelope is 44 mm in diameter and, excluding the B7 base pins, is 113 mm tall.

This exhibit was last updated on 02 July 2006