Matches 151 - 191 out of 191 < 1 2 3 4
Match Document Document Title
4088838 Voice response system  
Improvements in a push button signal receiving device for use in a voice response system, wherein in order to permit a push button signal from a user's telephone terminal to be received even during...
4061885 Digital tone decoder  
A digital tone decoder includes means for generating a timing signal, zero crossing counter means for generating a decode signal after a predetermined number of zero crossings in response to an...
4048450 Trunk circuit traffic analyzer  
Analyzer for monitoring the traffic of a group of trunks conveying decimal code signalling and dialling impulses and multifrequency code signalling and dialling signals. It comprises multifrequency...
4044206 Digital decoder for multiple frequency telephone signalling  
A multiple-frequency decoder which measures the two-tone output from a multiple-frequency dial type telephone and identifies what number was dialed. A unique binary code is produced as a timed...
4042787 Output processing and output coupling circuit for a digital tone receiver  
A circuit is provided to convert a set of mutually exclusive digital signals representing presence or absence of individual tones of a Dual Tone Multiple Frequency (DTMF), or 2-of-8 signal, system...
4042790 Voice guard circuit for a tone receiver  
Analog detection of invalid signal conditions at the input to a Dual Tone Multiple Frequency (DTMF) tone receiver is provided. The average of the voltage peak amplitudes of the signals in the upper...
4042788 Tone detector  
A digital tone detector is of the period detection type employing a digital counter which is stepped by means of a high speed clock. The counter is reset by zero-crossings of an analog tone signal....
4028501 Method and apparatus for translating multiple frequency signalling  
A multiple frequency signalling receiver translates combinations of tone signals received from a telephone set to derive binary two out of eight coded signalling. Received signals are directed by a...
4025730 In-band signal receiver  
A multifrequency signal receiver for an in-band audio frequency signalling system uses Discrete Fourier Transform or Fast Fourier Transform processing techniques or a combination of both to...
4016370 Digital tone decoder  
A decoder is disclosed for use in a communication system wherein bits of information are conveyed by the transmission, on a communication line, of code tones of distinctive frequencies each...
4016371 Frequency tone detection  
The detection of frequency tones, such as used in telephone pushbutton dialing to identify the digits of a called number, is performed in a digital manner which affords both speed and reliability...
4009353 Analog signal detection  
Disclosed is a method and apparatus for detecting the presence of signals, particularly touch-tone signals, of characteristic complex waveforms by comparing unknown signals with pre-specified...
4001521 Signal identification system  
A signal identification system, in which a signal of a specified frequency included in an analog signal indicated by an input pulse train converted from the analog signal is detected from the pulse...
3963878 Signal interpreting system for frequency selective multifrequency tone dialing  
A signal interpreting system for frequency-selective multi-frequency tone dialing includes a code tester and a code converter, and two serially connected delay means processing the output of said...
3961143 Multi-frequency signalling system  
A multi-frequency receiver is provided as part of a system able to evaluate the presence of 2 out of 5 signals and which incorporates 5 channel paths each including a parallel resonant circuit each...
3959603 Dual tone multiple frequency receiver/decoder  
A method and apparatus for separating the two analog component signals which make up a dual tone multiple frequency (Touch Tone) signal, converting the component signals into digital identification...
3934097 Multifrequency tone detection  
A method and apparatus for detecting multifrequency tones in a received signal by summing aperiodic samples and without using bandpass filters. In a receiver capable of detecting m different tones...
3931480 Time compression receiver  
Time compression receiver for detecting the signalling tones in a DTMF (dual tone multi-frequency) format present on eight receiver input lines. A multiplexer repeatedly samples the input signals...
3917912 Multifrequency dialing signal receiver for push-button type telephone systems  
A dialing signal receiver for use in a push-button type telephone system is described. In the proposed system, the multifrequency dialing signal is first divided into a pair of frequency...
3906365 Limiter circuit  
In a multi-frequency receiver for use in telecommunications system, tones within the audio frequency range are received. The tones transmitted are separated, amplified, and shaped into square...
3706855 GENERATOR FOR DIGITAL PULSE SIGNALS REPRESENTATIVE OF ANALOG SIGNAL PAIRS  
A technique of multifrequency pulsing consisting of transmitting a digitally valid number over pulse code modulated carrier from a time division multiplex office. The signals generated thereby...
3649771 VF PUSHBUTTON SIGNALING ARRANGEMENT  
This relates to "guard" arrangements for a VF receiver, especially for handling 2 × (1 out of 4) code signals from pushbutton subscriber sets. It is shown that if signals from a high-impedance...
3614322 SYSTEM FOR SELECTING AND REPRODUCING PERCEPTIBLE PROGRAMS  
A system for selecting and reproducing audio, video, or other humanly perceptible programs comprises a program source providing a multiplicity of program signals, a plurality of stations at which...
3582565 TONE CHANNELS FOR MULTIFREQUENCY RECEIVERS  
A tone channel of the type used in multifrequency receivers has in cascade an input band-pass filter that has a frequency curve similar to that of overcoupled filters, a limiter-amplifier, and an...
3562434 INTEROFFICE SIGNALING SYSTEM EMPLOYING SELECTED ONES OF THE TOUCH-TONE TELEPHONE FREQUENCIES FOR ESTABLISHING INTEROFFICE CONNECTIONS  
A system for providing interoffice connections as may be necessary to couple calling and called parties within a telephone network employing multifrequency signals of the Touch-Tone telephone type...
3539731 MULTIFREQUENCY SIGNAL RECEIVER  
3482051 VOICE-FREQUENCY KEY DIALLING FACILITY  
3428757 MULTIFREQUENCY INBAND TELEPHONE SIGNALING SYSTEMS  
3334190 Centralized repertory system for multifrequency signaling telephones  
3270144 Dial signal receiving facilities  
3259697 Telephone signaling system  
3231675 Multidigit register circuit  
3229041 Voice-frequency signal receivers as used in telephone systems  
3209076 Multi-frequency supervisory signal receiving system  
3140357 Multifrequency receiver  
3133994 Conference circuit for telephone switching systems  
3129290 Impulse register  
3114005 Inband signaling system  
3057964 Multifrequency signaling receiver  
2847508 Stage-by-stage all-relay telephone switching system using voice frequency control  
2832834 Signalling arrangement for telecommunication systems  
Matches 151 - 191 out of 191 < 1 2 3 4