JP2005045748A - Audio transmission control circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an audio transmission control circuit which attains enhancement in economical efficiency and construction efficiency of a wiring quantity so as to realize a control signal line by laying around two wires for each speaker. <P>SOLUTION: When transmitting audio signals from a broadcast sound source through an amplifier to speakers of a terminal via an audio transmission line, in an audio transmission part, the audio signal is digitized, a relay switch at the side of each speaker is selectively controlled in a time division multiplex manner under sequence control, and the audio signal is outputted to a digital signal transmission line via a selective relay switch. At the side of each speaker, a reception part which receives the digital signal time-compressed at the side of the audio transmission part via said common digital signal transmission line, and which applies time-expansion thereto, comprises a switch control part which recognizes a digital signal corresponding to the relevant speakers and controls said relay switch. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an audio transmission control circuit for sending system-specific switch information to a place where a speaker is installed in a local broadcast and controlling on / off of the speaker.

  In this type of audio transmission control circuit, the simplest circuit configuration for selectively ringing speakers arranged at various locations on the premises is to selectively control an on / off switch corresponding to each speaker prepared on the transmission side. In this case, the audio transmission line must be wired for each speaker. Usually, for N speakers, 2N in the case of the 2-wire system and 3N in the case of the 3-wire system are required. For this reason, the amount of wiring becomes enormous, which is uneconomical.

  Therefore, a relay switch is provided on each speaker side, and a method of branching the distribution from the common audio transmission line to each speaker is adopted, and the control signal of these relay switches is transmitted from the broadcasting sound source transmission side wirelessly. The output is also put to practical use in so-called TDM (Time division Multiple Access), currently TCP / IP (LAN).

However, wireless control is unavoidable for malfunction due to disturbance, and depending on the installation location of the speaker, it may become impossible to control due to the radio wave barrier.
JP-A-10-174186 JP-A-9-149497

  The present invention has been made on the basis of the above circumstances, and can reliably control a relay switch for turning on / off a speaker connected to an audio transmission line, and a control signal line is connected to each speaker. Therefore, an object of the present invention is to provide a voice transmission control circuit in which the wiring amount is economical and the construction efficiency is improved so that it can be realized by drawing two wires.

  For this reason, in the present invention, in the audio transmission control circuit for sending on-site system switch information to the place where the speaker is installed in the local broadcasting and controlling the on / off of the speaker, the audio transmission line is transmitted from the broadcast sound source via the amplifier. Therefore, the audio transmission unit that transmits the audio signal to each speaker of the terminal has a sequence control circuit for selectively controlling the relay switch on each speaker side by the time division multiplexing method, and the voice recognition prepared for each speaker. Means for converting an analog signal sent from the amplifier via an IC into a digital signal, and digital signal transmission via a selection relay switch that is turned on / off by time division control of the sequence control circuit Each speaker side via the common digital signal transmission line, A receiving unit that receives a time-compressed digital signal on the voice transmitting unit side and extends the time, and a switch control unit that recognizes the digital signal corresponding to the speaker and controls the relay switch. It is characterized by that.

  As an embodiment of the present invention, a selection switch group corresponding to each speaker is provided in the amplifier between a broadcast sound source and a voice recognition IC, and each speaker has a selection switch group. Equipped with a dip switch group for selecting whether or not to send a signal to the corresponding relay switch is effective in realizing control diversity.

  With this configuration, the present invention can achieve transmission of the control signal to each speaker by routing the two wires by using the time division of the control signal. Can be planned.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In the audio transmission control circuit according to the present invention, the switch information for each system is sent to the place where the speaker is installed in the local broadcasting and the on / off of the speaker is controlled. In this case, the audio transmission unit 1 is a microphone or the like. An audio signal is transmitted from the broadcast sound source 2 to the speakers SP-1 to SP-n of the terminal via the amplifier 3 and the audio transmission line 4.

  The voice transmitting unit 1 includes a sequence control circuit 5 for selectively controlling the relay switches RS-1 to RS-n on each speaker side by a time division multiplexing system, and a voice recognition IC 6− prepared for each speaker. Means for converting an analog signal sent from the amplifier 3 through 1 to 6-n into a digital signal, in this embodiment, A / D converters 7-1 to 7n, and the digital signal to the sequence control circuit 5 And an interface 10 for outputting to the digital signal transmission line 9 via selection relay switches 8-1 to 8-n which are turned on / off by the time division control.

  On the other hand, each speaker side receives a digital signal time-compressed on the audio transmission unit 1 side via a common digital signal transmission line 9 routed by two lines, and a reception unit 11 for time expansion, And a switch control unit 12 that recognizes a digital signal corresponding to the speaker and controls one of the relay switches RS-1 to RS-n corresponding to the speaker.

  Furthermore, in this embodiment, the amplifier 3 is provided with selection switch groups 13-1 to 13-n corresponding to each speaker between the broadcast sound source 2 and each of the voice recognition units 1C6-1 to 6-n. Yes. In this embodiment, a special switch 13-R for realizing voice transmission corresponding to all speakers in an emergency is also provided.

  Each speaker is equipped with a dip switch group 14 for selecting whether or not to send a signal to one of the relay switches RS-1 to RS-n corresponding to the selection switch group.

  In such a configuration, whether or not to use the speaker can be set in advance by the selection setting of the dip switch group 14. For example, five dip switches 14-a to 14-e are provided in each receiving unit 11 corresponding to five speakers.

  Further, by using the dip switches 14-a to 14-e in combination, it is possible to realize selection setting for use of many speakers. For example, the dip switch 14-a is 1, the dip switch 14-b is 2, the dip switch 14-c is 4, the dip switch 14-d is 8, and the dip switch 14-e is 16. Thus, by selecting a plurality of dip switches, for example, by selecting the dip switch 14-a of the constellation 1 and the dip switch 14-b of the constellation 2, it is obtained by the calculation of (1 + 2 = 3). The use of the third speaker can be selected. Such setting is effective in realizing control diversity.

  Therefore, in the audio transmission unit 1, the sound by the audio signal from the broadcast sound source 2 is selected for each speaker by manual on / off control of the switches of the selection switch groups 13-1 to 13-n. . That is, as a control signal, an analog signal sent to the voice recognition IC is converted from a high level to a low level of the voice signal and converted into a digital signal by the A / D converter.

  Then, the selection relay switch is controlled to be turned on / off by a control signal from the sequence control circuit 5, whereby a digital signal compressed by time division is received by each speaker via the digital signal transmission line 9. Sent to the department. Here, the digital signal is time-expanded, and the switch control unit 12 can turn on the corresponding relay switch to give an audio signal to the speaker and make it ring. When the switch 13-R is set to ON, the selection relay switch is turned ON so that all the speakers set to ON by the dip switch are sounded.

  In this case, unlike the control by radio, there is no malfunction due to radio interference and no control due to radio wave barrier, and the relay switch for turning on / off the speaker connected to the audio transmission line 4 can be reliably controlled, Moreover, the control signal line can be realized by drawing two lines for each speaker. Accordingly, it is possible to improve the economical efficiency of the wiring amount and the construction efficiency.

  It is a circuit block diagram which shows embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Audio | voice transmission part 2 Broadcasting sound source 3 Amplifier 4 Audio | voice transmission line SP-1 to SP-n Speaker RS-1 to RS-n Relay switch 5 Sequence control circuit 6-1 to 6-n Voice recognition IC
7-1 to 7n A / D converters 8-1 to 8-n selection relay switch 9 digital signal transmission line 10 interface 11 reception unit 12 switch control unit 12
13-1 to 13-n Selection switch group 13-R Switch 14 Dip switch group

Claims (3)

In the audio transmission control circuit that sends the switch information by system to the place where the speaker is installed in the local broadcasting and controls the on / off of the speaker.
An audio transmission unit that transmits an audio signal to each speaker of a terminal from a broadcast sound source via an amplifier via an audio transmission line is a sequence control for selectively controlling a relay switch on each speaker side by a time division multiplexing method A circuit, means for converting an analog signal sent from the amplifier through a voice recognition IC prepared for each speaker into a digital signal, and the digital signal is turned on / off by time-division control of the sequence control circuit An interface for outputting to a digital signal transmission line via a selection relay switch;
Each speaker side receives the digital signal time-compressed on the audio transmission unit side through the common digital signal transmission line, recognizes the digital signal corresponding to the speaker, and the reception unit that expands the time, A voice transmission control circuit comprising: a switch control unit that controls the relay switch.   2. The voice transmission control circuit according to claim 1, wherein a selection switch group corresponding to each speaker is provided in the amplifier between a broadcast sound source and a voice recognition IC.   The voice according to claim 2, wherein each speaker is equipped with a dip switch group for selecting whether or not to send a signal to the relay switch corresponding to the selection switch group. Transmission control circuit.

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