Title:
Reverberation circuit
United States Patent 1947621


Inventors:
Schreiber, Ernst H.
Application Number:
US61720132A
Publication Date:
02/20/1934
Filing Date:
06/14/1932
Assignee:
AMERICAN TELEPHONE & TELEGRAPH
Primary Class:
Other Classes:
84/DIG.26, 333/28R
International Classes:
G10K15/10
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