3866206 is referenced by 13 patents and cites 3 patents.

A remote electrical signalling system in which emergency call stations are manually operable to communicate with a home station, and a confirmation signal is automatically transmitted back from the home station when a call signal has been properly received. The call stations each include an electromechanical generator to power both a emergency signal transmitter section and a confirmation signal receiver section. Switch means are provided to direct a limited duration generator output first to the transmitter section and then to the receiver section. Power is recycled back to re-energize the transmitter section if a confirmation signal is not received within a pre-determined period of time.At the home station emergency calls are received and the call station identified. A blocking circuit prevents the recording of an identifying digit or the transmission of a confirmation signal unless the previous digits of the call station identification have been recorded.

Title
Emergency signalling system having manually operated generator
Application Number
05/379,967
Publication Number
3866206
Application Date
July 17, 1973
Publication Date
February 11, 1975
Inventor
Rane Subhash R
Labib Ahmed H
DeGiorgio John A
Assignee
Solid State Technology
IPC
H04b 01/04
G08B 25/01
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