Title:
Method and system of secret communication
United States Patent 2463502
US Patent References:
High-frequency signaling system
- - 1638925
Suppression of echoes and singing in four-wire circuits
- - 1653738
Echo-suppressor circuits
- - 1711562
High-frequency signaling system
- - 1638925
Suppression of echoes and singing in four-wire circuits
- - 1653738
Echo-suppressor circuits
- - 1711562
Inventors:
Atkins, Carl E.
Publication Date:
03/08/1949
View Patent Images:
Export Citation:
Assignee:
TUNG SOL LAMP WORKS INC
Primary Class:
Other Classes:
380/283
International Classes:
H04K1/02