ANTITHEFT DEVICE

PROBLEM TO BE SOLVED: To make a dummy plug to set a theft monitoring state unnecessary for a mooring type antitheft device which monitors theft of an article. SOLUTION: The antitheft device is constituted so as to make a resistance value of a resistor (R2) 10 set up in a second sensor jack section's circuit 29, 29 to be equivalent to the resistance value of a resistance object 1 inside a tag which divides power source voltage Vccof a power source terminal 24 together with a pull-up resistor (R1) 9, and to assign a dummy plug function to the resistor (R2) 10. By this configuration, when setting the article to the theft monitoring state, it is not necessary to insert the dummy plug in the sensor jack of out-of-use in the second sensor jack section's circuit 29, 29 one by one, and the antitheft device 30 can be set to the theft monitoring state by inserting only the sensor plug 4 to which the article is moored, in the sensor jack 5. Therefore, the state that the article cannot be put in the theft monitoring state can be avoided as it becomes unnecessary to always prepare the dummy plug, and problems of loss of the dummy plug is also solved. COPYRIGHT: (C)2004,JPO