Murdock model 442-A Rotary Spark Gap
date: label: date made
content: 1919
name: label: maker
content: Murdock, William
label: maker
content: Robbins & Myers Co.
notes: label: Description (Brief)
content: Marked: "Wm. J. Murdock Co. / Chelsea, Mass. / San Francisco". Motor plate reads: "The Standard Motor / Alternating Current / Volts 110 No. 39470 / Cycles 60 R.P.M. 8000 / H.P. 1/10 / Robbins & Myers / Co. Springfield, O. U.S.A." A twelve spoke wheel rotates between adjustable electrodes made of aluminum. This unit sold for $19.50 in 1919. Ref: Murdock Radio Apparatus Catalog - Bulletin 19, page 13.
label: Location
content: Currently not on view
place: label: inscribed on the motor plate
content: United States: Ohio, Springfield
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Franklin Wingard
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.320842
label: catalog number
content: 320842
label: accession number
content: 241556
objectType: label: Object Name
content: Spark Gap, Rotary
label: Object Name
content: spark gap
label: Other Terms
content: Spark Gap, Rotary; Components; Radio and Television; Radio and Television
physicalDescription: label: Measurements
content: overall: 6 1/2 in x 10 in x 7 1/2 in; 16.51 cm x 25.4 cm x 19.05 cm