McDonald "howl arrester"
date: label: date made
content: ca 1927
notes: label: Description (Brief)
content: Marked on box: "McDonald / Howl / Arrester / Clean / Reception / Assured / Patent / Pending"; on unit: "McDonald Tube Shield / Patented Dec. 7, 1926 / No. 1610208 / RS3". Scientific Products Canada, Limited / Licensed under Patents Pending / [distributed by] Spartan Electric Corporation / New York, N.Y., U.S.A." A hard rubber microphonic suppressor for 301-A and 201-A tubes. Includes original box and instruction sheet. This device would shield the tube elements against accidental shocks that often resulted in microphonic audio noises through the speaker. Reference: Box labeling and instruction leaflet.
label: Location
content: Currently not on view
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.321550.01
label: catalog number
content: 321550.01
label: accession number
content: 241556
label: patent number
content: 1610208
objectType: label: Object Name
content: radio tube shield
physicalDescription: label: Measurements
content: unit: 2 1/2 in x 2 in; 6.35 cm x 5.08 cm