History of Science Museum: Collection Database Search

Record Details

Marconi Radio Valve Type DEQ, by Marconi Company, English, c. 1923

preview image for Marconi Radio Valve Type DEQ, by Marconi Company, English, c. 1923
Inventory Number: 74920
Object Type:
Place Created: England United Kingdom Europe
Accession Number: 2004-9/192
Brief Description: Marconi Radio Valve Type DEQ (Dull Emitter Q), in thin glass envelope. With single wire filament running the length of the envelope and tensioned by a spring at end opposite the anode and grid brass supports. The anode and grid connections are on the envelope and pass to a shaped piece of glass rod that supports the electrodes. The grid helix can be clearly seen within envelope. A distinctive feature of DEQ valve is green band of paint around centre of envelope. Type DEQ valves had a very high impedance and primary function was as detector. Previously catalogued with five other valves: Marconi Type Q Valve (Inv. Num. 33191), Marconi Type V24 Valve (Inv. Num. 35245), Marconi DEV Valve (Inv. Num. 15771), Mullard ORA/B Valve (Inv. Num. 18833), Marconi FE2 Valve (Inv. Num. 92775).
Primary Inscriptions: "D.E.Q. BBC / 041 1_________" stamped on one side of exterior surface of bulb. "MARCONI _____ VALVES / ________ VARIOUS PATENTS" stamped on other side of exterior surface of bulb.
Provenance: Presented by the Marconi Corporation.
Collection Group: Marconi Collection
Material(s): Brass
assorted metals.
Height Width Depth Diameter Unit
78 30 mm


Image with multimedia irn 32481Image with multimedia irn 32482Image with multimedia irn 39791Image with multimedia irn 39792

Permalink: http://www.mhs.ox.ac.uk/object/inv/74920