Antitheft device for radio receiver in vehicle - only allows radio to function if stored data in radio is same as data stored in plug-in card

摘要

The anti-theft device, for radio, tape cassette or other electronic device in vehicle, has a card (3) or plug that fits into a slot (2) or recess in the receiver and contains a programmable memory. The memory stores a given combination of data. A second programmable memory is located inside the receiver and stores an identical combination of data. Both memories are read and their two combinations of data compared with one another. Only when the two combinations are the same can the receiver be switched on. The plug-in card or plug may also contain part of the receiver's circuitry.