Automatic emergency alarm reception apparatus using specific fre

Details Automatic emergency alarm reception apparatus using specific fre Automatic emergency alarm reception apparatus using specific fre

1996-10-07

1998-05-05

Vo, Nguyen

Telecommunications

Receiver or analog modulated signal frequency converter

Responsive to an input signal of particular predetermined...

455142, H04B 116

Patent

active

057490503

ABSTRACT:
An automatic emergency alarm reception apparatus for a broadcasting receiver which has a radio frequency part and a low frequency part, comprising an ON/OFF switch connected between the radio frequency part and the low frequency part, for turning on the broadcasting receiver when a specific frequency signal indicative of a state of emergency is received at an antenna of the broadcasting receiver, and an emergency alarm signal detection circuit for detecting the specific frequency signal from the radio frequency part to control the ON/OFF switch. The emergency alarm signal detection circuit includes an air defense alarm signal detection part and an air-raid alarm signal detection part. The air defense alarm signal detection part is provided with a band pass filter, a level comparator, an inverter, a pulse generator and a counter. The air-raid alarm signal detection part is provided with first to third band pass filters, first to third level comparators and a sequential detector. The emergency alarm signal detection circuit further includes an OR gate for performing an OR operation with respect to an output signal from the counter and an output signal from the sequential detector, and an R-S flip-flop for controlling the ON/OFF switch in response to an output signal from the OR gate.

REFERENCES:
patent: 3657655 (1972-04-01), Fukqata
patent: 3921074 (1975-11-01), Baird
patent: 4020421 (1977-04-01), Elder et al.
patent: 4079317 (1978-03-01), Baird
patent: 4334319 (1982-06-01), Gurry
patent: 4479252 (1984-10-01), Souchay et al.

Affiliated with

Also associated with

Rating

Automatic emergency alarm reception apparatus using specific fre does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Automatic emergency alarm reception apparatus using specific fre, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automatic emergency alarm reception apparatus using specific fre will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-71388