Browse Prior Art Database

Paging System

IP.com Disclosure Number: IPCOM000092188D
Original Publication Date: 1968-Oct-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 29K

Publishing Venue

IBM

Related People

Desblanche, AE: AUTHOR

Abstract

The system has a fixed installation and portable equipment. For the fixed installation, a building area, for example, is divided in several portions. Each portion is surrounded by a metallic wire or loop connected through a scanner to the RF emitter. A frequency selection system delivers to the emitter the frequency associated with the person to be called. Pulse frequency trains are sent over a loop, for example, loop n. In the portable equipment, an electromagnetic field is induced in the resonant circuit of Hartley oscillator in which the battery is replaced by a capacitor C. During the emission of pulse trains, this capacitor C is charged. Once the emitter interrupts its transmission, capacitor C is discharged and the oscillator transmits its own pulse train.

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Paging System

The system has a fixed installation and portable equipment. For the fixed installation, a building area, for example, is divided in several portions. Each portion is surrounded by a metallic wire or loop connected through a scanner to the RF emitter. A frequency selection system delivers to the emitter the frequency associated with the person to be called. Pulse frequency trains are sent over a loop, for example, loop n. In the portable equipment, an electromagnetic field is induced in the resonant circuit of Hartley oscillator in which the battery is replaced by a capacitor C. During the emission of pulse trains, this capacitor C is charged. Once the emitter interrupts its transmission, capacitor C is discharged and the oscillator transmits its own pulse train. When an RF is detected in the scanned loop, the receiver delivers a DC voltage to control devices not shown.

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