Radio Instrument Co. radio power supply

Radio Instrument Co. radio power supply

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Usage conditions apply
Description (Brief)
Used in Supreme Court case, 1935. Marked: BS31247; tags: (1) In the U.S. Pat. Office Interference Nos. 51204-21702-53153-53154-53155. Lowell & Dunmore Exhibit No. 46. (2) U.S. District Court District of Delaware Plaintiffs Exhibit No. 67. (3) Supreme Court of the U.S., Oct. Term 1935, Plaintiffs--Respondents Exhibit no. 20. Bureau of Standards. No.: R-597. Rectifier unit was employed as the power supply for the A.C. operated receiver (Cat. #321925). Rectifying tube is a UV201-A with grid and plate tied together to form a diode. Transformer contains five windings, one supplying 6 volts AC to the rectifier filament, one supplying 6 volts to receiving tube filaments, one supplying 300 volts for filtering and use as plate voltage, and one supplying four volts to the filament of a "Tungar" rectifier tube. The 110 volt input or primary winding was tapped to furnish plate voltage to the "Tungar" gas rectifier. This latter tube supplied DC current to the filed coil of a Magnavox speaker. In this case, the choke employed for filtering purposes was the twin filed coil of the Kolster Arc. (Cat. No. 321936) Reference: Bureau of Standards "Scientific Paper No. 450" (1922).
Currently not on view
Object Name
Rectifier Unit
power supply
date made
c 1922
ca 1922
associated person
Radio Instrument Co.
overall: 12 in x 8 3/4 in x 8 1/2 in; 30.48 cm x 22.225 cm x 21.59 cm
ID Number
catalog number
accession number
Credit Line
from John B. Brady, thru Mrs. John B. Brady
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Work and Industry: Electricity
Data Source
National Museum of American History
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