JPS6230400Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inspection device that enables rapid inspection of the state of a large number of two-terminal audio devices such as microphones connected to an amplifier.

Conventionally, when amplifying sound from a speaker using a mixing amplifier (mixer) to which multiple audio devices such as microphones and tape recording devices are connected, if there is a long connection cable between the audio devices, the operating status of the audio devices can be directly monitored from the mixer installation location. It is often impossible to see. If there is a malfunction in operation, it is not clear whether the problem is with the mixer, the connecting cable, or the audio equipment, so it is necessary to find out the cause and repair it, and wait for a long time before it can be used normally. It often took time. It is particularly difficult to detect failures when a large number of microphones are connected and their cables are crossed.

The purpose of the present invention is to improve the above-mentioned drawbacks, to provide a power source for testing in a device that performs operations such as amplification, to display operation indicators that are switched sequentially by a changeover switch, and to
An object of the present invention is to provide a device for inspecting the condition of audio equipment.

Embodiments of the present invention shown in the drawings will be described below. In the drawings, CH1, CH2, . . . CHn indicate each channel of the mixing amplifier, and a microphone, a tape recorder, etc. (not shown) are connected to the front stage, and a speaker, etc. (not shown) is connected to the rear stage. AMP indicates the operating circuit in each channel, and includes mixing operation and amplification circuits. DTR is a circuit for detecting disconnections and short circuits in microphones, etc. CG1, CG2...CGn are changeover switches that connect microphones, etc. to the movement detection circuit DTR, and RCT is a ring counter that obtains operation pulses for the changeover switch. . POS is a pulse oscillator,
The repetition frequency is selected to be a relatively slow value to the extent that it corresponds to the operation cycle when sequentially inspecting by manual operation, and the repetition frequency can be made variable by a variable resistor VR. The ring counter RCT is driven by the output of the pulse oscillator POS. SW-B is a switch used to connect and disconnect the output of the pulse oscillator POS to the ring counter RCT. In addition, the motion detection circuit DTR
consists of an oscillator OSC that oscillates a frequency for impedance measurement of microphones, etc., a series resistor RR, a differential amplifier DFA, a rectifier RC, and a comparator CMP. In the display device DSP, a light emitting diode LED is inserted into the collector circuit of the transistor. Switches SW-A and SW-C also operate in conjunction with each other, and in the illustrated position they are on the motion detection side of a microphone or the like.
That is, the switch SW-A is used to connect/disconnect the operation detection circuit DTR and the changeover switches CG1, CG2, . . . CGn, and the switch SW-C is used to reset the ring counter RCT. When switch SW-C is switched to the opposite side as shown in the figure, the output of each stage of ring counter RCT becomes "0", and changeover switch CG
1, CG2, . . . , the side connected to the operating circuit AMP is conductive, and the side connected to the switch SW-A is non-conductive.

Now, in order to test microphones, etc., set switches SW-A, SW-B, and SW-C to the positions shown in the figure, and then oscillate the pulse oscillator POS. The output pulses will sequentially pass through each stage of the ring counter RCT to "1". ”, along with the changeover switch CG1,
CG2... becomes conductive and non-conductive sequentially. Therefore, microphones etc. are sequentially connected and disconnected from the motion detection circuit DTR. Since a device number is attached to the changeover switch, that is, the microphone that performs the connection/disconnection operation, the device number can be displayed using the output of the ring counter RCT. For example, ENC is a binary code encoder, NDS is a numeric display (using a light emitting diode, etc.),
SGD converts binary code signals into segment decoders.
Use what is decoded into a segment display signal for displaying decimal digits. Therefore, the first pulse oscillator POS
When inspecting by output, the numeric display NDS
For example, indicates 01. On the other hand, since a microphone or the like is connected to the motion detection circuit DTR via the changeover switch CG, the motion detection circuit DTR compares the voltage across the series resistor RR with the oscillator output voltage in the differential amplifier DFA. When a fault occurs where the microphone side becomes open, the voltage across the resistor RR becomes zero, and if a short circuit occurs, the voltage across the resistor RR and the oscillator OSC become zero.
is equal to the output voltage of Therefore the comparator
By setting the operating point of the CMP, when the above-mentioned failure occurs, the operation indicator DSP operates and its light emitting diode
You can light up the LED. If pulses are supplied from the pulse oscillator POS for the number of microphones to be tested, when the light emitting diode LED of the display circuit DSP lights up, reading the number displayed on the device number display will immediately detect the malfunctioning microphone, etc. Prove. The overall condition can be inspected in a relatively short time, and if a defective condition is expected, the inspection can proceed while taking time to check the relevant equipment.

In the above case, when the microphone or the like is disconnected or short-circuited, the display will operate, but there is no way to distinguish between the two cases. Therefore the comparator
If CMP were to have a circuit configuration that distinguishes between a disconnection display and a short circuit display, a large number of elements would be used, but the status inspection would be more accurate and countermeasures could be taken quickly.

In this way, according to the present invention, even if there are a large number of devices to be tested, they can be sequentially tested by using a changeover switch and a device number display, which is effective in actual use, and is particularly effective in preventing failures. We can respond quickly and reliably. Furthermore, even if an extremely large number of devices to be tested are connected, the test can be performed efficiently.

[Brief explanation of the drawing]

The drawing is a circuit diagram showing the configuration of the present invention. CH1, CH2...CHn...Mixing amplifier channel, RCT...Ring counter, DTR...Operation detection circuit, DSP...Operation display, POS...Pulse oscillator, ENC...Binary code encoder, NDS...
...Numeric display.

Claims (1)

[Scope of Claim for Utility Model Registration] A device for connecting audio equipment and performing operations such as amplification is provided with an operation detection circuit for the audio equipment, the operation detection circuit has a built-in power supply for testing the audio equipment, and an output terminal of the power supply. In an audio equipment testing device, a two-terminal type audio equipment to be tested is connected to the equipment via a series resistor, and the voltage across the series resistor is compared with the test power output terminal voltage to test the state of the audio equipment to be tested. , a plurality of audio devices are connected to the motion detection circuit via a changeover switch, the changeover switches are automatically switched in sequence, the state of the audio devices is inspected, and the device number display of the audio device indicates the sound that is being detected. An audio equipment inspection device characterized by displaying equipment numbers.