COMBINED FIRE ALARM,BURGLAR ALARM,AND INTERCOMMUNICATION SYSTEM
United States Patent 3487404
US Patent References:
Electronic siren and communication apparatus
- - 3051944
Electronic sirens
- - 3137846
Electrical protective system
- - 3174143
Electronic siren and communication apparatus
- - 3051944
Electronic sirens
- - 3137846
Electrical protective system
- - 3174143
Inventors:
Midkiff, James C.
Publication Date:
12/30/1969
View Patent Images:
Export Citation:
Assignee:
AVCO CORP
Primary Class:
Other Classes:
340/541, 340/533, 340/577, 340/384.700, 331/47
International Classes:
G08B19/00; G08B1/08; G08B19/00; G08B3/00