Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Voice Control of Recording System

IP.com Disclosure Number: IPCOM000081271D
Original Publication Date: 1974-May-01
Included in the Prior Art Database: 2005-Feb-27
Document File: 2 page(s) / 32K

Publishing Venue

IBM

Related People

Raesz, R: AUTHOR

Abstract

An additional circuit is incorporated into a voice operated or controlled recording system for distinguishing incoming audio from line noise, and eliminating the possibility of system response due to playback.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Voice Control of Recording System

An additional circuit is incorporated into a voice operated or controlled recording system for distinguishing incoming audio from line noise, and eliminating the possibility of system response due to playback.

Circuit 1 is connected along buss 2 through separate lines to playback audio line 3 and incoming audio line 4. Lines 3 and 4 are connected to circulator 5 and dictation apparatus 6. Circulator 5 is connected to a telephone line along line 7. In circuit 1, the playback audio line 8 is connected to operational amplifier 9. R1 and R2 comprise a level setting. When playback audio peaks exceed the DC level at the negative input of operational amplifier 9, a positive pulse will be applied along line 10. The incoming audio steady state detect level is determined by R3 and R4. This level is set to be above any effects of line noise. C1 and D1 provide a change in detect level at the negative terminal of operational amplifier 11, when playback peaks cause a positive pulse at the output of operational amplifier 9.

Circuit 1 is designed to permit a fast rise, but a slow fall on the voltage across C1, thus providing sufficient integration to eliminate detection between playback peaks. When the incoming audio peaks exceed the voltage at the negative terminal of operational amplifier 11, positive pulses will be applied along line 12.

1

Page 2 of 2

2

[This page contains 2 pictures or other non-text objects]