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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
glass
assorted metals.
Dimensions:
Height Width Depth Diameter Unit
78 30 mm

Narratives

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