| 摘要 |
PROBLEM TO BE SOLVED: To provide a control system for superpositing voltage for automatically determining whether a DC voltage is to be superposed or not in a main device for supplying the DC power supply voltage to a sub device via a universal high-frequency connector and a cable, while it is supposed to a high-frequency signal. SOLUTION: A main device is provided with a determining circuit, a key is added to a cable for connecting the main device to a sub device, and it is automatically determined whether the key is fitted to the determination circuit or not, thus automatically controlling whether a DC voltage should be superposed from the main device. |
