Title:
Switching apparatus for sound reproducing systems
United States Patent 1931035


Inventors:
Louis, Reynolds John
Application Number:
US18032327A
Publication Date:
10/17/1933
Filing Date:
04/01/1927
Assignee:
ELECTRICAL RES PROD INC
Primary Class:
Other Classes:
369/198
International Classes:
G03B31/00
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