RCA NBC "bullet" condenser microphone

RCA / NBC "bullet" condenser microphone

Usage conditions apply
RCA / NBC condenser microphone. Vertical cylindrical case, cone tope, gauze covered opening at side marked NBC, marked: VIII on bottom, cord attached. A thin, tightly stretched diaphragm of aluminum alloy, spaced 2/1000 inch from flat brass disc form a condenser. The diaphragm, moved by sound waves, varies the capacity of the condenser. Electrical output is feeble but registers faithfully a wider range of input sound, free of the noise evident in carbon microphones. First used regularly in 1925, limited use to 1938. Required amplification close to microphone, but only two stages were feasible at the time.
Currently not on view
Object Name
condenser microphone
radio microphone
Other Terms
condenser microphone; Audio Devices
date made
RCA Corporation
overall: 8 3/4 in x 4 in x 5 in; 22.225 cm x 10.16 cm x 12.7 cm
ID Number
catalog number
accession number
Credit Line
from National Broadcasting Company, Inc.
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Work and Industry: Electricity
Data Source
National Museum of American History
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