Radio Instrument Co. radio power supply

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).