Catalogue
52 of 655 records previous / next
Mullard Radio Valve Type ORA/B, by Mullard Radio Valve Company, c. 1922
Inventory Number: 18833
Date: c. 1922
Maker Details: Signed by Mullard Radio Valve Co.
Inscription: "MULLARD RADIO VALVE / 36" stamped on one side of exterior surface of bulb. "BBC / PROTECTED BY PATENT / 254" stamped on other side of exterior surface of bulb.
Size: 75 mm in overall length
Materials: Glass, rubber?, assorted metals.
Other Given Number(s): Christie's 197.
Notes:
Mullard Radio Valve Type ORA/B, in thin glass envelope. ORA stands for Oscillator, Rectifier, and Amplifier. Valve was of bright emitter type and had a mu (amplification factor) of 8.5. In construction, valve has a rubber? skirt and familiar tubular anode. Grid is of curved folded arrangement and has single strand filament, tensioned by support arm. 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), Marconi DEQ Valve (Inv. Num. 74920), Marconi FE2 Valve (Inv. Num. 92775).
52 of 655 records previous / next
Record mode: Basic | Medium Images | Large Images | Documents (0)