DE3 pair Marconi – Amplion AML2/30 – Electron 404 – D3 Mullard – Ediswan PV6DE pair

Description

This section shows seven interesting valves, from left:

Pair of Marconi DE3 dull emitter triode of 1923, one with metal base.

Amplion type AML2/30 “shortpath’ taken from the design of the Cosmos SP18 is a triode.

Electron 404 power valve R type helix.

D3 Mullard a  4-pin triode and dates from 1924. It is a dull emitter triode and the two red rings denote the HF variant; ones with two green rings were for LF (AF)

Pair Ediswan PV6DE is a low impedance output triodes.