Browse Prior Art Database

Network for Providing Comparison Hysteresis

IP.com Disclosure Number: IPCOM000095157D
Original Publication Date: 1965-Sep-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 47K

Publishing Venue

IBM

Related People

Clapper, GL: AUTHOR

Abstract

This network provides discrimination against noise and improves the hysteresis action of comparing devices forming a part of speech analyzing systems. Such devices comprise that portion of the system utilized for the detection of local maxima signals representing peak energies in voice sounds of the speech spectrum.

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Network for Providing Comparison Hysteresis

This network provides discrimination against noise and improves the hysteresis action of comparing devices forming a part of speech analyzing systems. Such devices comprise that portion of the system utilized for the detection of local maxima signals representing peak energies in voice sounds of the speech spectrum.

The network comprises Nand's N1... N4. These provide the local maxima signals respectively designated Mh, Mi, Mj, Mk and comparing devices which include transistors X1-X2, X4-X5, and X7-X8. The collectors of these transistors connect to the Nand's and also to a +6 volt supply by way of 2K resistors. The emitters of these transistors are connected in pairs to node points E1, E2, and E3. These are separated from each other by 820 ohm resistors. The nodes are further connected to constant current generators which include transistors X3, X6, and X9. The constant current generators together with the resistor network connected to it act as variable degenerative emitter load resistors for the transistor pairs in the comparing devices.

Analog signals, derived from integrated outputs of frequency analyzers, not shown, which are tuned to the various frequencies of the sound spectrum, are fed into the bases of the transistors in the comparing devices. In this network, a nominal gain results when no voltage differences exist at the inputs. The gain for the units associated with a local maximum is increased. The gain for...