Abstract: Apparatus for detaching an electronic surveillance tag from an article to which it is attached, the tag having a locking member therein and defining an exteriorly accessible passage to the locking member, comprises a motor, a probe rotatable by the motor for movement in the passage into and from unlocking relation with the locking member and drive controller for the motor. The drive controller includes circuitry for (1) establishing a time period for energization of the motor, (2) effecting first sense movement of the probe during a first portion of the time period, (3) discontinuing movement of the probe during a second portion of the time period, and (4) effecting second sense movement of the probe following expiration of the second portion during a third portion of the time period.

Abstract: A combination comprises an EAS tag having an exteriorly accessible channel and a releasable lock for securing the tag to an article, the lock being disposed at a given distance along the channel, and a detacher for detaching the tag from the article, the detacher including a probe adapted for movement in the passage, a drive unit energizable for moving the probe in the channel, and timing circuitry for controlling energization of the drive unit such that the drive unit moves the probe through distance corresponding to the given distance. The timing circuitry controls energization of the drive unit to move the probe through a distance corresponding to the given distance in a first sense for disposing the probe in releasing engagement with the lock. The timing circuitry controls energization of the drive unit to move the probe through a distance corresponding to the given distance in a second sense for moving the probe from engagement with the lock means to the exterior of the tag.

Abstract: An EAS system in which a transmitter alternately drives first and second antennas with the same coded message signal in its entirety. The antennas, in turn, transmit first and second signals each containing the coded message signal into respective first and second partially overlapping parts of an interrogation zone. Also disclosed is an antenna structure comprised of a plurality of loops extending one after the other and successive ones of which are of opposite phase. One of the loops circumscribes an area which is smaller than each of the other loops to realize reduced coupling to adjacent structures.

Abstract: In an EAS system a transmitter alternately drives first and second antennas with the same coded message signal in its entirety. The antennas, in turn, transmit first and second signals each containing the coded message signal into respective first and second partially overlapping parts of an interrogation zone. Also disclosed is an antenna structure comprised of a plurality of loops extending one after the other and successive ones of which are of opposite phase. One of the loops circumscribes an area which is smaller than each of the other loops to realize reduced coupling to adjacent structures.

Abstract: An electronic article surveillance tag comprises an electrical power source, receiver circuitry for receiving coded messages for diverse state dispositions of the tag, decoder circuitry for decoding received coded messages and for directing the tag into active and inactive states, alarm circuitry for providing audible output indication of unauthorized activity in respect of the tag in an active state thereof, and motion detector circuitry operative upon disposition of the tag in an inactive state for lessening drain on the electrical power source and further operative on detecting movement of the tag when in the inactive state to dispose the tag in an active state with increased drain on the electrical power source. The alarm circuitry and the motion detector circuitry share common electrical circuit elements, inclusive of a piezoelectric unit.

Abstract: In an electronic article surveillance system, a jamming apparatus is provided for establishing a jamming zone in which tags can be situated and not respond to message signals from a surveillance system transmitter and in which the surveillance system receiver can be situated and still respond to tag signals.

Abstract: The invention provides in combination, an electronic article surveillance system for disposition in an area to be subjected to such surveillance and control circuitry connected with the system, the system generating a readiness signal when prepared to effect electronic article surveillance and being thereafter responsive to an input signal to commence electronic article surveillance, the control circuitry being responsive to the readiness signal selectively to generate the input signal and being adapted to suppress generation of the input signal responsively to further input to the control circuitry indicative of the existence of a predetermined condition. The predetermined condition is the presence in the area of a further electronic surveillance system which has not generated its readiness signal, and the invention looks to interconnecting the further system to the control circuitry.

Abstract: A tag for use in a magnetic article surveillance system employs an antenna means responsive to a transmitted magnetic signal and a piezoelectric means responsive to the antenna means for generating an audible acoustic signal. Embodiments are provided responding to unmodulated, amplitude modulated, and frequency modulated magnetic signals.