| 摘要 |
PURPOSE:To control remotely a power supply state of a microphone and propriety of speech or the like by using a phantom power supply. CONSTITUTION:In the remote controller for a phantom feeding system microphone in which supply currents divided equally to both signal lines of microphone cords are supplied from a power supply circuit and a shield wire of the microphone cord is used for a return conductor, an output voltage from the phantom power supply is used to activate any of reference voltage circuits 21a-21d through on/off of analog switches 22a-22d selected to cause voltage fluctuation and it is outputted to the microphone cord from relevant terminals 11a-11d to activate the controller comprising a comparator 53a connecting to a drive circuit of the microphone unit 35a connecting to the microphone cord to control the propriety of speech of the microphone unit 35a based on the fluctuation voltage from the reference voltage circuits 21a-21d, an analog switch 55a and flip-flop circuits 56a, 60a. |
