Automatic audio-visual program control apparatus

Claim 2

An audio-visual display system comprising: magnetic tape recorder means for recording audio program signals on magnetic tape and for reproducing same during playback of a recorded tape; a plurality of auxiliary display units for producing audio effects or visual effects or both; cue encoding means coupled to the tape recorder means for recording plural channel cue signals on the magnetic tape at desired points in the audio program, said cue encoding means including means for producing time-multiplexed signals which comprise repetitive groups of pulses and means for independently changing the time interval between each of a plurality of selected pulses and a corresponding adjacent pulse in each group to thereby provide a plurality of independnet control channel cue signals for control channels designated by the selected pulses; and cue decoding means coupled to the tape recorder means and to the auxiliary display units during tape playback and responsive to reproduced control channel cue signals for automatically and independently controlling the different auxiliary display units in step with the playback of the recorded audio program signals.

Claim 3

An audio-visual display system in accordance with claim 1 wherein the cue encoding means includes: a clock pulse generator; a series of cascaded delay circuits, the first of which is coupled to the clock pulse generator; means for adding the output signals from the clock pulse generator and the delay circuits to produce a train of cue pulses; and means for independently changing the time delay of each delay circuit for providing a plurality of independent control channel cue signals.

Claim 4

An aduio-visual display system in accordance with claim 2 wherein the time delay changing means for at least one of the delay circuits comprises an analog device for varying the time delay in a continuous manner.

Claim 5

An audio-visual display system in accordance with claim 1 wherein the system further includes: multiplex mixer means coupled between the cue encoding means and the tape recorder means for converting the control channel cue signals to tone burst signals and combining same with at least some of the audio program signals for enabling the combined signals to be recorded on a common track on the magnetic tape; and frequency selective signal separator means coupled between the tape recorder means and the cue decoding means during tape playback for separating the cue signal tone bursts from the intermiNgled audio program signals and for converting same to pulse type signals for use by the cue decoding means.

Claim 6

An audio-visual display system in accordance with claim 4 wherein: the multiplex mixer means is constructed so that the level of the recorded cue signal tone bursts is substantially less than the average level of the recorded audio program signals with which it is combined; and the signal separator means includes frequency selective means for boosting the level of the cue signal tone bursts relative to the level of the lower frequency components of the intermingled audio program signals before the cue signal tone bursts are separated from the audio program signals.

Claim 7

An audio-visual display system in accordance with claim 4 wherein the multiplex mixer means comprises: an audio-frequency oscillator; gate circuit means coupled to the output of the oscillator and responsive to the control channel cue signals produced by the cue encoding means for producing at the output of such gate circuit means tone burst signals corresponding in position and duration to the pulses of the control channel cue signal; and circuit means for mixing the tone burst signals with an audio program signal.

Claim 8

An audio-visual display system in accordance with claim 4 wherein the signal separator means comprises: high-boost filter circuit means for boosting the level of the cue signal tone bursts relative to the level of the lower frequency components of the intermingled audio program signals; sharply tuned bandpass circuit means coupled to the high-boost filter circuit means for passing substantially only the cue signal tone bursts; circuit means coupled to the output of the bandpass circuit means for converting the tone bursts to pulse type signals and for supplying same to the cue decoding means; and low-boost filter circuit means for boosting the level of the lower frequency components of the audio program signals relative to the higher frequency components, such circuit means being constructed so that the low frequency boost equalizes the low frequency attenuation experienced in the high-boost filter circuit means to develop an audio output signal for use by a loudspeaker type reproduction system.

Claim 9

An audio-visual display system in accordance with claim 7 wherein the multiplex mixer means comprises: an audio-frequency oscillator; gate circuit means coupled to the output of the oscillator and responsive to the control channel cue signals produced by the cue encoding means for producing at the output of such gate circuit means tone burst signals corresponding in position and duration to the pulses of the control channel cue signals; and circuit means for mixing the tone burst signals with an audio program signal to provide the combined signals for the magnetic tape recorder means.

Claim 10

An audio-visual display system in accordance with claim 1 wherein one pulse in each group is a sync pulse and the other are position-modulated cue pulses for different control channels and wherein the cue decoding means comprises: automatic gain control circuit means for receiving and conditioning the cue pulses; sync separator means responsive to the sync pulse in each group for producing separate sync signals; saturable switch circuit means responsive to the cue pulses and the separate sync signals for producing separate sets of width modulated pulses on a plurality of output lines, the pulses on any given output line being width modulated in accordance with the position modulation of the pulses for a particular one of the control channels; a plurality of width detector circuit means individually coupled to different ones of the saturable switch circuit output lines for producing separate control signals for the different control channels; and a plurality of signal coupling means for individually coupling the width detector circuit means to different ones of the auxiliary display units.

Claim 11

AN audio-visual display system in accordance with claim 9 wherein the cue encoding means comprises: a clock pulse generator; a series of cascaded delay circuits, the first of which is coupled to the clock pulse generator; means for adding the output signals from the clock pulse generator and delay circuits to produce a train of cue pulses; and means for independently changing the time delay of each delay circuit for providing a plurality of independent control channel cue signals.

Claim 12

An audio-visual display system in accordance with claim 9 wherein the cue pulses received by the automatic gain control circuit means are negative-going pulses and such automatic gain control circuit means comprises: a field effect transistor having gate, source and drain electrodes; circuit means for biasing the field effect transistor to a normally conductive condition; circuit means for enabling the gate electrode of the field effect transistor to receive the incoming negative-going cue pulses; a p-n-p transistor having bare, emitter and collector electrodes; circuit means for coupling the base electrode of the p-n-p transistor to the drain electrode of the field effect transistor and for biasing the p-n-p transistor to a normally conductive condition; and output circuit means coupled to the collector electrode of the p-n-p transistor for providing negative-going amplitude discriminated and conditioned cue pulses.

Claim 13

An audio-visual display system in accordance with claim 9 wherein the saturable switch circuit means comprises: a series of cascaded switch circuits each comprising n-p-n transistor, circuit means for applying operating voltage between the emitter and collector electrodes of the n-p-n transistor, a p-n-p transistor having its collector electrode connected to the base electrode of the n-p-n transistor and having its base electrode connected to the collector electrode of the n-p-n transistor and circuit means for biasing both transistor to a normally non-conductive condition; circuit means for supplying the separate sync signals to the base electrode of the n-p-n transistor in the first switch circuit in the series for repetitively turning such first switch circuit on; circuit means for coupling the n-p-n collector electrode of each switch circuit to the n-p-n base electrode of the next switch circuit in the series for turning the latter switch circuit on when the earlier switch circuit turns off; circuit means for supplying the cue pulses to the p-n-p emitter electrodes of all of the switch circuits for turning off the switch circuit which is turned on when a cue pulse occurs; and the output lines for the saturable switch circuit means being individually coupled to the n-p-n collector electrodes in different ones of the switch circuits.

Claim 14

An audio-visual display system in accordance with claim 9 wherein each width detector circuit means includes: one-shot multivibrator circuit means coupled to one of the saturable switch circuit output lines and responsive to the leading edge of each width modulated pulse appearing on such output line for producing a reference pulse of predetermined width; add circuit means responsive to each width modulated pulse and to the one-shot reference pulse produced by the leading edge thereof for producing an output pulse having a width corresponding to the difference in widths of the width modulated pulse and the reference pulse; and integrator circuit means for integrating the add circuit output pulses for producing a control signal for the particular control channel with which the width detector circuit means is associated.

Claim 15

An audio-visual display system in accordance with claim 9 wherein each signal coupling means includes: light emitting means coupled to the output of one of the width detector circuit means for emitting light in response to the appearance of a control signal at such output; light responsive means responsive to light emitteD by the light emitting means for producing a control effect; and circuit means coupled to the light responsive means and to one of the auxiliary display units and responsive to the control effect produced by the light responsive means for controlling the auxiliary display unit in accordance therewith.

Claim 16

An audio-visual display system in accordance with claim 9 wherein: the cue encoding means includes a clock pulse generator; a series of cascaded delay circuits the first of which is coupled to the clock pulse generator, means for adding the output signals from the clock pulse generator and the delay circuits to produce a train of cue pulses, and means for independently changing the time delay of each delay circuit for providing a plurality of independent control channel cue signals, the time delay changing means for at least one of the delay circuits comprising an analog device for varying the time delay in a continuous manner; and the width detector circuit means and signal coupling means for the control channel employing the analog device includes one-shot multivibrator circuit means responsive to the leading edge of each width modulated pulse for the analog control channel for producing a comparison pulse, comparing circuit means for comparing the width modulated pulses with the comparison pulses for producing an error signal, a servo mechanism controlled by the error signal for enabling a continuous adjustment of the auxiliary display unit controlled by the analog control channel, and means coupled to the servo mechanism for adjusting the pulse width of the one-shot comparison pulses until a practically zero error signal is produced by the comparing circuit means.

Claim 17

An audio-visual display system comprising: magnetic tape recorder means for reproducing audio program signals and plural channel cue signals recorded on a magnetic tape wherein the recorded cue signals are in the form of repetitive groups of time-multiplexed pulses wherein one pulse in each group is a sync pulse; and the others are position-modulated pulses for different control channels; a plurality of auxiliary display units for producing audio effects or visual effects or both; automatic gain control circuit means coupled to the tape recorder means during tape playback for receiving and conditioning the cue signal pulses; sync separator means responsive to the sync pulse in each group for producing separate sync signals; saturable switch circuit means responsive to the cue signal pulses and the separate sync signals for producing separate sets of width modulated pulses on a plurality of output lines, the pulses on any given output line being width modulated in accordance with the position modulation of the pulses for a particular one of the control channels; a plurality of width detector circuit means individually coupled to different ones of the saturable switch circuit output lines for producing separate control signals for the different control channels; and a plurality of signal coupling means for individually coupling the width detector circuit means to different ones of the auxiliary display units for automatically and independently controlling the different auxiliary display units in step with the playback of the recorded audio program signals.

Claim 18

An audio-visual display system comprising: magnetic tape recorder means for reproducing audio program signals and plural channel cue signals recorded on a magnetic tape wherein the recorded cue signals are in the form of repetitive groups of time-multiplexed pulses wherein one pulse in each group is a sync pulse; and the others are position-modulated pulses for different control channels; a plurality of auxiliary display units for producing audio effects or visual effects or both; automatic gain control circuit means coupled to the tape recorder means during tape playback for receiving and conditioning the cue signal pulses; sync separator means responsive to the sync pulse in each group for producing separate sync signals; saturable switch circuit means responsive to the cue signal pulses and the separate sync signals for producing separate sets of width modulated pulses on a plurality of output lines, the pulses on any given output line being width modulated in accordance with the position modulation of the pulses for a particular one of the control channels; a plurality of width detector circuit means individually coupled to different ones of the saturable switch circuit output lines for producing separate control signals for the different control channels; and a plurality of signal coupling means for individually coupling the width detector circuit means to different ones of the auxiliary display units for automatically and independently controlling the different auxiliary display units in step with the playback of the recorded audio program signals.

Claim 19

An audio-visual display system comprising: magnetic tape recorder means for recording audio signals on magnetic tape and for reproducing same during playback of a recorded tape; an auxiliary display unit for producing audio or visual effects; means for producing cue signals in the form of audio-frequency tone bursts in which the frequency of the oscillations in each tone burst is greater than a predetermined frequency; signal combining means for combining such tone bursts with an audio program signal and supplying the combined signals to the magnetic tape recorder means for recording same on a common tract on a magnetic tape; first frequency selective circuit means couPled to the magnetic tape recorder means during tape playback for separating the cue signal tone bursts from the audio program signal; said circuit means including high-boost filter circuit means for boosting the level of signal components at frequencies greater than the predetermined frequency relative to the level of signal components at frequencies less than the predetermined frequency and sharply tuned bandpass circuit means coupled to the output of the high-boost filter circuit means for passing substantially only the cue signal tone bursts; means responsive to the separated cue signal tone bursts for automatically controlling the auxiliary display unit in step with the playback of the recorded audio program signal; and second frequency selective circuit means coupled to the magnetic tape recorder means during tape playback for separating the audio program signal from the cue signal tone bursts for providing an uncontaminated audio program signal for use by a loudspeaker type sound reproduction system, said second circuit means including low-boost filter circuit means coupled to the output of the high-boost filter circuit means for boosting the level of signal components at frequencies less than the predetermined frequency relative to the level of signal components at frequencies greater than the predetermined frequency, such low-boost filter circuit means being constructed so that the low frequency boost equalizes the low frequency attenuation provided by the high-boost filter circuit means.

Claim 20

An audio-visual display system comprising: magnetic tape recorder means for recording audio signals on magnetic tape and for reproducing same during playback of a recorded tape; an auxiliary display unit for producing audio or visual effects; means for producing cue signals in the form of audio-frequency tone bursts in which the frequency of the oscillations in each tone burst is greater than a predetermined frequency; signal combining means for combining such tone bursts with an audio program signal and supplying the combined signals to the magnetic tape recorder means for recording same on a common tract on a magnetic tape; first frequency selective circuit means couPled to the magnetic tape recorder means during tape playback for separating the cue signal tone bursts from the audio program signal; said circuit means including high-boost filter circuit means for boosting the level of signal components at frequencies greater than the predetermined frequency relative to the level of signal components at frequencies less than the predetermined frequency and sharply tuned bandpass circuit means coupled to the output of the high-boost filter circuit means for passing substantially only the cue signal tone bursts; means responsive to the separated cue signal tone bursts for automatically controlling the auxiliary display unit in step with the playback of the recorded audio program signal; and second frequency selective circuit means coupled to the magnetic tape recorder means during tape playback for separating the audio program signal from the cue signal tone bursts for providing an uncontaminated audio program signal for use by a loudspeaker type sound reproduction system, said second circuit means including low-boost filter circuit means coupled to the output of the high-boost filter circuit means for boosting the level of signal components at frequencies less than the predetermined frequency relative to the level of signal components at frequencies greater than the predetermined frequency, such low-boost filter circuit means being constructed so that the low frequency boost equalizes the low frequency attenuation provided by the high-boost filter circuit means.

Claim 21

An audio-visual display system in accordance with claim 17 wherein the signal combining means includes notch filter circuit means sharply tuned to the frequency of the tone burst oscillations for minimizing tone burst frequency components in the audio program signal before it is combined with the cue signal tone bursts.

Claim 22

An audio-visual display system in accordance with calim 17 wherein the second frequencey selective circuit means includes notch filter circuit means sharply tuned to the tone burst oscillation frequency for minimizing tone burst frequency components in the audio program signal to be supplied to the sound reproduction system.

Claim 23

An audio-visual display system in accordance with calim 17 wherein the second frequencey selective circuit means includes notch filter circuit means sharply tuned to the tone burst oscillation frequency for minimizing tone burst frequency components in the audio program signal to be supplied to the sound reproduction system.

Claim 24

An audio-visual display system in accordance with claim 17 wherein: the first frequency selective circuit means includes notch filter circuit means sharply tuned to the tone burst oscillation frequency for minimizing tone burst frequency components in the audio program signal before it is combined with the cue signal tone bursts; and the second frequency selective circuit means includes notch filter circuit means sharply tuned to the tone burst oscillation frequency for minimizing tone burst frequency components in the audio program signal to be supplied to the sound reproduction system.

Claim 25

An audio-visual display system comprising: magnetic tape recorder means for recording audio program signals on magnetic tape and for reproducing same during playback of a recorded tape; at least one auxiliary display unit for producing audio effects or visual effects or both; and cue encoding means coupled to the tape recorder means for recording channel cue signals on the magnetic tape at desired points in the audio program, said cue encoding means including means for producing signals which comprise repetitive groups of at least two pulses and means for independently changing the time interval between a selected pulse and a corresponding adjacent pulse in each group to thereby provide a control channel cue signal for a control channel designated by the selected pulse further including cue decoding means coupled to the tape recorder means and to the auxiliary display unit during tape playback and responsive to a reproduced control channel cue signal for automatically controlling the auxiliary display unit in step with the playback of the recorded audio program signals.

Claim 26

An audio-visual display system comprising: magnetic tape recorder means for recording audio program signals on magnetic tape and for reproducing same during playback of a recorded tape; at least one auxiliary display unit for producing audio effects or visual effects or both; and cue encoding means coupled to the tape recorder means for recording channel cue signals on the magnetic tape at desired points in the audio program, said cue encoding means including means for producing signals which comprise repetitive groups of at least two pulses and means for independently changing the time interval between a selected pulse and a corresponding adjacent pulse in each group to thereby provide a control channel cue signal for a control channel designated by the selected pulse further including cue decoding means coupled to the tape recorder means and to the auxiliary display unit during tape playback and responsive to a reproduced control channel cue signal for automatically controlling the auxiliary display unit in step with the playback of the recorded audio program signals.