URGENCY ANNOUNCING APPARATUS

• US 3,860,746 A
• Filed: 05/21/1973
• Issued: 01/14/1975
• Est. Priority Date: 05/20/1972
• Status: Expired due to Term

• Current Assignee: Takeshi Takeuchi
• Original Assignee: Takeshi Takeuchi
• Inventors: Takeuchi, Takeshi
• Primary Examiner(s): Richardson, Robert L.
• Application Number:
  US05/362,252
• Time in Patent Office: 603 Days
• Field of Search: 178/5.6,5.8R,DIG.23,DIG.13 325/308,64,57,53
• US Class Current: 725/33
• CPC Class Codes: G08B 25/085 using central distribution transmission lines
• CPC Class Codes: G08B 27/008 with transmission via TV or radio broadcast
• CPC Class Codes: H04N 7/10 Adaptations for transmission by electrical cable H04N7/12 takes precedence

Abstract

An urgency announcing apparatus for use in wired television signal transmitting system includes providing at the head end of the system, such as a community antenna television system or a master antenna television system, a modulator for modulating frequencies of urgency announcing signals transmitted from an image signal generator such as an industrial television camera, a video tape recorder, or the like to those in the intermediate frequency band for television receivers and also providing at the side of each television receiver of the system a change-over switchgear for interrupting television signals when urgency announcing signals are transmitted and sending urgency announcing signals to the intermediate frequency amplifying stage of the television receiver.

Claims

1. An urgency announcing apparatus for use in a wired television signal transmitting system having a head end and trunk lines leading to subscribers television sets comprising modulating means for converting alarm signals into frequencies in the radio frequency band, a mixing means which receives broadcast television signals and said converted alarm signals from said modulating means, control means operatively connected to said mixing means, said control means including a first filter means passing only broadcast television signals, second filter meaNs passing only converted alarm signals, first and second relay switches controlled by the output from said second filter means, an intermediate frequency amplifier means, said first switch having a first normal operable position providing a first connection to said intermediate frequency amplifier means to relay broadcast television signals via said fist filter means, said first switch having a second alarm position in which said first connection is terminated and a second connection is established between the output of said second filter means and said intermediate frequency amplifier to relay alarm signals, said second switch having a normal position which disconnects a power source from the television set and an alarm position which connects said power source to the television set while by-passing the normally operated on-off switch on the television set, whereby converted alarm signals from said mixing means pass to the television set via said second filter means, said first switch, and said intermediate frequency amplifier means to interrupt any television broadcast signals regardless of the position of the manually operated on-off switch on the television set.

2. An urgency announcing apparatus according to claim 1 wherein said second filter means comprises a first filter element and a second filter element each of which passes only said converted alarm signals, said first filter means and said first and second filter elements being connected in parallel, a relay connected to the output of said third filter element for operating said first and second switches, whereby actuation of said relay moves said first switch from said first normal operable position to said second alarm position and moves said second switch from said normal position to said alarm position.

3. An urgency announcing apparatus according to claim 2 including circuit means between said second filter element and said intermediate frequency amplifier means, said first switch when in said second alarm position completing said circuit means to provide a path through said second filter element, said first switch, and said intermediate frequency amplifier means.

4. An urgency announcing apparatus according to claim 1 wherein a single relay simultaneously actuates said first and second switches.

5. An urgency announcing apparatus according to claim 1 including splitter means connected to said second filter means, one circuit means connecting said splitter to said first switch and another circuit connected to a high frequency amplifier, a relay for actuating said first and second switches, a circuit between said high frequency amplifier and said relay including an electric power amplifier for amplifying the signals from the high frequency amplifier, whereby alarm signals passing through said second filter means actuate said relay to move said first switch from said first normal operable position to said second alarm position and to move said second switch from said normal position to said alarm position.

6. An urgency announcing apparatus according to claim 5 wherein said one circuit means includes said first switch whereby when the latter is in its second alarm position, a path is provided between said second filter means, said first switch and said intermediate frequency amplifier means.