Title:
Electrostatic telephone
United States Patent 1550381


Inventors:
Joseph, Massolle
Hans, Vogt
Josef, Engl
Application Number:
US51842521A
Publication Date:
08/18/1925
Filing Date:
11/28/1921
Assignee:
TRI ERGON LTD
Primary Class:
Other Classes:
381/174
International Classes:
H04R19/02
View Patent Images: