| 摘要 |
PROBLEM TO BE SOLVED: To increase an output level of an FM signal outputted during power failure without using expensive components.SOLUTION: Since a PIN diode D1 in a circuit A is ON while a power supply is energized and is OFF while the power supply is cut off, an AMP1 is separated from the photodiode PD1 during power failure. Since a PIN diode D2 in a circuit B is ON while the power supply is energized and is OFF while the power supply is cut off, a capacitor C6 is turned from earth to open in the power failure. Consequently an FM signal from the photodiode PD1 is outputted at an extremely large output level from an FM terminal 12 through a coil L1 and a photo MOS relay 11 during the power failure. |
