| 摘要 |
An alarm system primarily for a motor vehicle includes an electronic circuit (10) which is arranged to respond to a drop in the supply voltage derived from the vehicle's battery as a result of energisation of any electrical equipment on the vehicle whilst the alarm is operative. To detect mechanical interference with the vehicle, an optional movement detector unit (23) is provided, which includes a movement sensitive switch (24) operating to energise a dummy load (R20) and thereby trigger the alarm. The system may be adapted for use with non-motorised vehicles, and electrical equipment, and as an intruder alarm in domestic or commercial premises. <IMAGE> |
