Browse Prior Art Database

Teletypewriter Detector

IP.com Disclosure Number: IPCOM000095574D
Original Publication Date: 1964-Mar-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 42K

Publishing Venue

IBM

Related People

Gindi, AM: AUTHOR [+2]

Abstract

Solid-state magnetic amplifiers can replace the electro-mechanical receive-relays of multiplex teletypewriter circuits if a single oscillator is provided at the multiplex receiving station and each teletypewriter loop is connected to control the resonance of the associated magnetic amplifier at the oscillator frequency.

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Teletypewriter Detector

Solid-state magnetic amplifiers can replace the electro-mechanical receive- relays of multiplex teletypewriter circuits if a single oscillator is provided at the multiplex receiving station and each teletypewriter loop is connected to control the resonance of the associated magnetic amplifier at the oscillator frequency.

Oscillator 1 serves the entire multiplex receiving station by providing an AC electrical signal of fixed frequency. There may be a large number of teletypewriter circuits, each with its own receiving mechanism, of which mechanisms 10, 20 and 90 only are shown in detail. Each receiving mechanism provides the required complete isolation between input and output.

Teletype signals, coded as intervals of current (mark) and no-current (space) on a current loop, are used to saturate or not saturate the magnetic core. Receiving mechanism 10 has coupled to it a teletype current loop 11 which serves as the primary winding of transformer core 12. Core 12 is of a linear type and by its condition, either saturated or unsaturated, controls the impedance of winding 13. Winding 13 and capacitor 14 form a tank circuit which is resonant or non resonant at the oscillator frequency depending upon the state of core 12. The output of this tank circuit is monitored by an amplifier 16 which provides the output signal. The resonant or nonresonant condition of the tank circuit is reflected by different voltages appearing across the tank circuit whi...