| 摘要 |
PURPOSE:To inspect a number of devices to be inspected and to discover failures eariler in a sure manner, by providing a power supply for inspection in a device operating amplifiers and sequentially switching an operation display device corresponding to audio devices through selector switches. CONSTITUTION:A microphone and a tape recorder and the like are connected at the pre-stage of channels CH1-CHn of a mixing amplifier, and speakers or the like are connected to the post-stage, and the channels CH1-CHn are provided with selector switches CG11-CGn1, CG21-CGn2, and operation display devices DSP1- DSPn. An operation detecting circuit DTR is connected to the switches CG11- CG1n and CG12-CG2n, and the circuit DTR is provided with an oscillator OSC oscillating frequencies for measurement and a DC power supply +V and the like. Between the switches CG11-CG1n and the circuit DTR, a ring counter RCT and manual operation selector switches SW-A-SW-D are provided, so that the operating state of the channels CH1-CHn can be inspected by the circuit DTR. |
