The Azide Process. Technical article on cathode technology

Barkhausen-Kurz (B-K) Mode Oscillators. Early Centimetric Wave Generation.

Early Bi-Grid Valves.

How To Build a Two Valve Set A practical project from cigarette cards in 1929

How To Make a Valve Amplifier A practical project from cigarette cards in 1924

The Cossor Wuncell Range The first oxide-coated valves produced in Britain.

The Dawn of Broadcasting in the UK The earliest history of Radio Broadcasting

DER Valves. Evolution of Early Dull Emitter Valves.

Early Transmitting Valves. WW1 valve technology.

The Ediswan Safety Cap. To avoid HT across the filament.

The First Kurhaus Radio-Concerts. Part of the history of Dutch broadcasting

Sealing of Glass to Other Materials. Taken from Vacuum Tubes by K Spangenberg (1948) ¹⁰⁰¹.

The History of the UK Valve An excellent book - a `must have'

Interservice Valve Bases. Early UK Armed Services valve bases.

How To Make Your Own Wireless A practical project from cigarette cards in 1924

Osram Valves. The Early Days

The Philips-Mullard (PM) Series. The first 'azide ' valves

Type Q and type V24 Valves. The first hard vacuum valves designed in Britain

The S625 Valve. The World's first HF screen-grid tetrode.

Shortpath Construction.

Silica Valves. A Mullard speciality

Valve Adverts An archive of historical valve adverts.