| 摘要 |
PURPOSE:To obtain an antitheft action free from incorrect functioning by detecting sound waves propagated through a vehicle body or the like when the vehicle body or the like is contacted, setting a solid-state sound recording device by means of an output from an amplifier of high sensitivity combining the propagated sound waves and frequency bands, and by producing a warning sound signal by wireless transmission. CONSTITUTION:A signal of a sound produced when a vehicle body is contacted and detected with a detector 1 such as a microphone is amplified with an amplifier 2 of high sensitivity combining the propagated sound and its frequency bands and is applied to a solid-state sound recording device 3. This causes the solid-state sound recording device 3 to be driven and to be set to a recording condition. At the same time, a 1st transceiver 4 carried on the vehicle is driven to produce a warning sound signal by wireless transmission. The warning sound signal is received with a 2nd transceiver 5 carried by an owner of the vehicle. When the owner hears the received signal and learns that the vehicle is in a condition of being robbed, the owner operates a pushbutton or the like to drive a warning device such as a horn via a transceiver 4 to stop the robbery in advance. |
