摘要 |
A vehicle burglar alarm lock has a body capable of being locked to an annular handle of a steering wheel. An alarming circuit in the body is capable of being actuated for operation. The alarming circuit has an independent battery set not being connected to a vehicle battery as a power supply. A central processing unit is operated responsive to a signal from a pressure variation detecting loop. The pressure variation detecting loop comprises: a filtering loop, a power regulating loop, a pressure sensing loop, a low pass amplifying loop, and positive and negative comparing loops for amplifying the signals and then outputting the signal to the central processing unit. The central processing unit executing preset sound and light alarming step in response to the signal. |