Tag device and method for electronic article surveillance

A method for effecting electronic article surveillance with a system of a type having transmissions inclusive of a first high frequency signal and a second lower frequency signal, such second signal having a modulation characteristic therewith, and wherein generally rectangular tag devices are attached to said articles for receipt of said transmissions and for reradiation concurrently of said first and second signals thereof, said method comprising the fabrication of said tag devices by the steps of:

• (a) providing first and second circuit elements to be of a type exhibiting fixed inductive and capacitive reactances;
• (b) providing a third circuit element to be of type exhibiting voltage dependent capacitive reactance and forming an electrical series circuit with said first, second and third circuit elements;
• and
• (c) configuring said first and second circuit elements with respective geometric diversities, such that said second circuit element predominates in receipt of said second frequency transmitted signals over receipt thereby by said first circuit element, and such that said series circuit is resonant at said first frequency
• said step (b) being further practiced by selecting said third circuit element to coordinate the voltage dependent capacitive reactance thereof with said second frequency transmitted signals received by said second circuit element to enhance capacitive reactance change in said third circuit element in response to such signals received by said second circuit element.

A method for effecting electronic article surveillance with a system of type having transmissions inclusive of a first high frequency signal and a second lower frequency signal, such second signal having a modulation characteristic therewith, and wherein generally rectangular tag devices are attached to said articles for receipt of said transmissions and for reradiation concurrently of said first and second signals thereof, said method comprising the fabrication of said tag devices by the steps of:

• (a) providing first and second circuit elements to be of type exhibiting fixed inductive and capacitive reactances;
• (b) providing a third circuit element to be of type exhibiting voltage dependent capacitive reactance and forming an electrical series circuit with said first, second and third circuit elements;
• and
• (c) configuring said first and second circuit elements with respective geometric diversities, whereby said first circuit element extends longitudinally of said device and is of first transverse dimension, and whereby said second circuit element extends longitudinally of said device at least in part jointly spacedly with said first circuit element and is of second transverse dimension substantially exceeding said first transverse dimension to effect predominant different receipt by said first and second circuit elements of said first and second frequency transmitted signals.