| 摘要 |
PURPOSE:To ensure the protection against robbery by sending the identical signal with a preset secret code to a receiving IC for switching on an ignition circuit or a door-lock circuit. CONSTITUTION:Switches 9 and 16 are turned on by an engine key to connect a transmitting and a receiving circuit 1 and 2 to power sources 17 and 27. A secret cord is inputted by a keyboard 11, and a signal corresponding to the secret code is transmitted by a code-generating circuit 12. The signals is sent through a pulse-modulating circuit 13 and an amplifying circuit 14, and converted into infrared rays by a light-emitting diode 15 for transmission. This light signal is received by a light-receiving diode 21 of the receiving circuit 2 for converting into an electric signal. The signal is sent through an amplifying circuit 22 and a detection wave-form shaping circuit 23, and compared with the preset secret code in a code-reading circuit 24. When the signal is found identical with the secret cord, the circuit 24 sends a signal to switch on a power amplifier circuit 25, and operates a control circuit 26. Consequently, an ignition circuit 4 is brought into operation. The same process is performed for door locking. |
