US3851332A

US3851332A - Oscillator controlled color organ display

Info

Publication number: US3851332A
Application number: US00382748A
Authority: US
Inventors: R Dougherty
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-07-26
Filing date: 1973-07-26
Publication date: 1974-11-26
Anticipated expiration: 1991-11-26

Abstract

A color organ display system or music in color (MIC) system is provided for achieving musical tone separation expressed in terms of color utilizing a power supply, pre-amp and automatic volume regulator, and an RC Audio Frequency Phase Shift Oscillator. The power supply is a standard piece of equipment which can be readily purchased at any electronic supply store. The pre-amp and automatic volume regulator as well as the RC Audio Frequency Phase Shift Oscillator is comprised of transistors, capacitors and resistors which are all readily intergratable. One pre-amp and automatic volume regulator for a multi-channel operation is required. One RC Audio Frequency Phase Shift Oscillator (channel unit) is required for each note utilizing a different color light to display the note which is currently being played by the instrument to which the MIC system is connected. The tones, as for example, from a radio or an organ or jukebox, requires that separation be applied simultaneously to a bank of channels of one or more oscillator circuits which are held just barely below oscillation. Power from the many tones to be separated provides the small additional signal level necessary to drive one or more of the separate and independent oscillator circuits into operation. Thus, the output of the one or more oscillators when operating are amplified sufficiently to provide separate indicator lamp displays.

Description

Dougherty, Jr.

[ OSCILLATOR CONTROLLED COLOR ORGAN DISPLAY [76] Inventor: Robert J. Dougherty, Jr., 2306 Curcar Dr., Mississippi City Station, Gulfport, Miss. 39501 Primary E.\'aminerHarold I. Pitts Attorney, Agent, or Firm-Pugh & Laiche [57] ABSTRACT A color organ display system or music in color (MIC) system is provided for achieving musical tone separation expressed in terms of color utilizing a power sup- [451 Nov. 26, 1974 ply, pre-amp and automatic volume regulator, and an RC Audio Frequency Phase Shift Oscillator. The power supply is a standard piece of equipment which can be readily purchased at any electronic supply store. The pre-amp and automatic volume regulator as well as the RC Audio Frequency Phase Shift Oscillator is comprised of transistors; capacitors and resistors which are all readily intergratable. One pre-amp and automatic volume regulator for a multi-channel operation is required. One RC Audio Frequency Phase Shift Oscillator (channel unit) is required for each note utilizing a different color light to display the note which is currently being played by the instrument to which the MIC system is connected. The tones, as for example, from a radio or an organ or jukebox, requires that separation be applied simultaneously to a bank of channels of one or more oscillator circuits which are held just barely below oscillation. Power from the many tones to be separated provides the small additional signal level necessary to drive one or more of the separate and independent oscillator circuits into operation. Thus, the output of the one or more oscillators when operating are amplified sufficiently to provide separate indicator lamp displays.

9 Claims, 3 Drawing Figures BACKGROUND OF THE PRESENT INVENTION The present invention relates to an audio frequency filter circuit which separates music, speech or other audible t tones from one another dependent upon frequency or pitch and presenting them for visual display on one or more colored lamps. The instant MIC system of musical tone separation adds an exciting and interesting dimension to the enjoyment of hi-fidelity sound. With the addition of color and sight, music contains a new depth and understanding. The human voice is divided and displayed into a flash of color while an orchestra is separated and flows in waves of color and brilliance. The content ofsound is unmasked for all to see and viewed in an unforgettable way. A

This is accomplished'by using a unique electronic circuit whereby musical notes are separated with each directed to its own colored light. For example, the pure tone of a guitar will light one color at a time while the saxophone (rich in harmonics) may light several lamps. Speech, with its many and varied tones, creates a splash of random colors.

Heretofore, MIC systems required the use of expensive and bulky inductor-capacitor filter circuits. In these systems it was necessary to use a series of these filters to obtain the desired narrow band width for proper separation thereby adding to the bulk and cost of the system. Furthermore, several of these filter circuits required power for their operation from the signal source itself thereby limiting the type of circuits from which they could be powered. Generally, these types of systems are not adjustable as to band width and sensitivity and many channels would be activated by one strong signal. A further disadvantage from a presentday manufacturing standpoint is the fact that these circuits did not lend themselves to intergration because of large inductance and compacitance values required for low audio signal frequencies.

The instant MIC system is inexpensive, compact, and light-weight. It contains no bulky and costly filter circuits and is readily intergrated using current'manufacturing' techniques in electronics. Moreover, it requires no power from the signal source for its operation and is therefore compatible with any sound system. For example, its input can be from a small transistor radio, a TV, tape. phonograph or HI-FI equipment. The number of simultaneous inputs is unlimited and it can be used with monaural, stereo, four-track, four-channel, etc. The range of power acceptance is very wide and varies from transistor radios to high powered stereo equipment upwards to jukeboxes and theatre systems.

The instant MIC system is powered by 110 AC current with the musical input from one or more speaker terminals.- It is self-adjusting over wide ranges of projustable at the desire of the user as is the sensitivity of each channel in the overall response.

It is an object of the present invention to provide a small, light-weight and inexpensive frequency separator circuit which is readily intergratable and is adjustable as to band width and sensitivity requiring no power from the signal source and being capable of handling wide variations of signal power and programming material for use in connection with Music In Color Systems.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic of the power supply for the present invention;

FIG. 2 is a schematic of the pre-amp and automatic volume regulator for the present invention; and

FIG. 3 is a schematic of a single channel unit which is actually an RC Audio Frequency Phase Shift Oscillator.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The power supply unit shown in FIG. 1 is a standard bridge rectifier which is comprised of a plug 10, fuse ll, switch 12, neon pilot lamp 14 with its current limiting resistor 13, which serves as the input to DC transformer 15. Transformer 15' is a step-down 12.6 volts, 1.2 amps filament transformer which has connected to its output a bridge rectifier 16 whose output is con nected to a PI-type of RC filter. This filter is comprised of capacitors l7 and 19 and resistor 18. The power supply provides two positive outputs, namely, a poorfiltered full-wave DC (point 1) and a well-filtered DC (point 2). Point 1 powers the lamp circuits and good filtering is not a requirement. Point 2 powers the preamp and tone selection circuits. The voltage output of both points varies widely depending on the number of tone selecting circuits activated and the number of lamps that are lit at any one time. This wide variation is necessary to reduce the overall illumination when many lamps are lit aiding the ear-eye response. As a general rule the number of channels powered by this power supply unit is variable up to about 24 channels.

ulator. One is required for each system of about 24 channels. The pre-amp and automatic volume regula tor acts as an amplifier on soft music passages and a volume limiter on loud passages. Capacitor 20 .and 21 couple the input signals from the speaker terminals into the MIC system-

Resistors

22 and 23 prevent the signal power from one speaker from affecting the other speaker. The number of speaker inputs can be increased by the addition of capacitor 20 and resistor 22 combinations connected to the junction of resistor 22 and resistor 23. Resistor 24 is a limiting resistor which establishes the overall signal input to theunit. For small signal sources, e.g. transistor radios, etc., it must be reduced. For large signal sources, e.g. juke-boxes, high power stereo equipment, it must be advanced. Resistor 25 provides forward bias for transistor 27. Resistor 26 is the collector load for transistor 27 while capacitor 28 is a coupling capacitor to the common signal line to which the tones selected circuits are connected.

Automatic volume regulation is accomplished through two actions. Firstly, the voltage available at power point 2 is reduced when several lamps are lit due to power supply loading and the voltage drop across resistor 18. This reduces the operating voltage for transistor 27 and reduces the output of the pre-amp. The second action involves the bass-emitter rectification of the input signal by transistor 27 which reverse biases the stage on high level input. This reverse biasing action also reduces the output of the pre-amp on loud programming material. Variable resistor 24 is adjusted for the general overall level of signal power to be accepted and the automatic limiting action of the pre-amp handles wide variations around this general level.

The basic configuration of the transistor 38 circuit is that of a RC (resistor-capacitor) Phase Shift Audio Sine Wave Oscillator commonly referred to as a channel unit illustrated in FIG. 3. Resistor 30 couples the input signal from the pre-amp and provides a high degree ofisolation. The RC combination of

capacitors

31, 32, 33 and resistors 34, 35 and the base-emmiter resistance of transistor 38 comprise the 180 phase shifting network and are mainly responsible for the frequency selection. These values change with each channel unit.

Resistor 37 is the forward bias for transistor 38 while resistor 36 is the collector load and has a relatively low ohmic value thereby reducing the feedback amplitude to a point near or below that required for sustained oscillation. The low reactance of coupling capacitor 39 and the loading effect of variable resistors 40 completes the oscillation inhibiting action. Variation of the ohmic value of the resistor 40 affects the degree of loading and thusly the band width and sensitivity of the regenerating transistor 38 circuit.

The compound coupled NPN (negative-positivenegative) transistor 41, PNP transistor 44, and NPN transistor 45 circuits for lamp powered gain is selected for its low input (light loading) requirement and the low idling" current characteristic thereby reducing the effects on transistor 38 and the heat-sinking requirements later on. Transistors 41, 44 and 45 directly coupled provide the necessary current gain for the lamp power at lamp 46. Resistor 43 is a current limiting resistor for transistor 44 while resistor 47 provides runaway protection for transistor 45. Resistor 47 also establishes the average current through lamp 46 by setting the emmiter bias on transistor 45. Lamp 46 is the indicator lamp which visually shows the tone output required at normal viewing levels. Capacitor 42 acts to dampen the switching action of transistor 41, transistor 44, and transistor 45 and improves the viewing results.

ously discussed provide a phase shift of 60each which completes the necessary 360 feedback to sustain oscillation at one audio frequency, namely, the frequency which creates the 60 phase angle in the RC sections. By operating the oscillator circuit with a small collector load, feedback amplitude is reduced to a point very close or below that required for sustained oscillation. Further loading of the circuit output completes the inhibiting process. Upon the application of the proper input frequency, sufficient signal level is attained to produce oscillation. In effect, the dampened oscillator becomes a regenerative amplifier at one certain frequency. Amplification through a series of stages of transistors 41, 44 and 45 completes the channel operation thereby providing a visual color signal for lamp 46.

Although but one specific embodiment of this invention is herein shown and described, it will be understood that details of the construction shown may be altered or omitted without departing from the scope and spirit of the present invention as defined in the following claims.

What is claimed is:

1. An RC Phase Shift Audio Sine Wave Oscillator device which is readily intergratable for use in connection with a color organ display system wherein musical notes are electronically separated and modified to generate impulses for actuating a series of colored lamps, said device comprised of:

a. a transistor having a base, collector and emitter;

b. phase shifting network combination of capacitors and resistors connected between the collector and the base of said transistor, the base being connected to a common signal line for receiving signal sources; and

c. a multi-stage amplifier connected across the collector and a source of electricity for powering a lamp.

2. The device as defined in claim 1 wherein said phase shifting networks primary responsibility is that of frequency selection, and wherein there isfurther included:

d. an isolation resistor connected between the base of said transistor-and the common signal line which is adaptable to be connected to a pre-amp and automatic volume regulator;

e. a forward bias resistor having one of its ends connected to the base of said transistor, the other of its ends being adapted to be connected to a DC power point; and

. a collector load resistor having one of its ends connected to the collector of said transistor, the other of its ends being adapted to be connected to a DC power point.

3. The device as defined in claim 2 wherein:

g. a coupling capacitor is connected at one of its ends to the collector of said transistor while the other of its ends is connected to the input stage of said multi-stage amplifier which acts to reduce the feedback amplitude to a point near or below that required for sustained oscillation of said oscillator.

4. The device as defined in claim 3 wherein:

h. a variable resistor is connected between the input of said multi-stage amplifier and grounds, the variation of said variable resistors ohmic value affecting the degree of loading and thusly the band width and sensitivity of said transistor.

5. The device as defined in claim 4 wherein:

i. a visual color lamp is placed at the output of said multi-stage amplifier.

6. The device as defined in claim 5 wherein:

j. a pre-amp and automatic volume regulator is connected to said common signal line.

7. The device as defined in claim 6 wherein:

said pre-amp and automatic volume regulator is comprised of;

a transistor having a collector, base and emitter, the

emitter being connected to the ground;

a coupling capacitor connected between the common signal line and the collector of said transistor;

a connector load resistor connected between a DC power point and the collector of said transistor;

a forward bias resistor connected between the collector and base of said transistor; and

an RC combination connected to one end of a variable limiting resistor, the other end of said variable limiting resistor being connected to the base of said transistor, the RC combination being connectable tlon.

Claims

1. An RC Phase Shift Audio Sine Wave Oscillator device which is readily intergratable for use in connection with a color organ display system wherein musical notes are electronically separated and modified to generate impulses for actuating a series of colored lamps, said device comprised of: a. a transistor having a base, collector and emitter; b. phase shifting network combination of capacitors and resistors connected between the collector and the base of said transistor, the base being connected to a common signal line for receiving signal sources; and c. a multi-stage amplifier connected across the collector and a source of electricity for powering a lamp.

2. The device as defined in claim 1 wherein said phase shifting network''s primary responsibility is that of frequency selection, and wherein there is further included: d. an isolation resistor connected between the base of said transistor and the common signal line which is adaptable to be connected to a pre-amp and automatic volume regulator; e. a forward bias resistor having one of its ends connected to the base of said transistor, the other of its ends being adapted to be connected to a DC power point; and f. a collector load resistor having one of its ends connected to the collector of said transistor, the other of its ends being adapted to be connected to a DC power point.

3. The device as defined in claim 2 wherein: g. a coupling capacitor is connected at one of its ends to the collector of said transistor while the other of its ends is connected to the input stage of said multi-stage amplifier which acts to reduce the feedback amplitude to a point near or below that required for sustained oscillation of said oscillator.

4. The device as defined in claim 3 wherein: h. a variable resistor is connected between the input of said multi-stage amplifier and grounds, the variation of said variable resistor''s ohmic value affecting the degree of loading and thusly the band width and sensitivity of said transistor.

5. The device as defined in claim 4 wherein: i. a visual color lamp is placed at the output of said multi-stage amplifier.

6. The device as defined in claim 5 wherein: j. a pre-amp and automatic volume regulator is connected to said common signal line.

7. The device as defined in claim 6 wherein: said pre-amp and automatic volume regulator is comprised of: a transistor having a collector, base and emitter, the emitter being connected to the ground; a coupling capacitor connected between the common signal line and the collector of said transistor; a connector load resistor connected between a DC power point and the collector of said transistor; a forward bias resistor connected between the collector and base of said transistor; and an RC combination connected to one end of a variable limiting resistor, the other end of said variable limiting resistor being connected to the base of said transistor, the RC combination being connectable to a set of audio speakers.

8. The device as defined in claim 7 wherein: said pre-amp and automatic volume regulator is intergratable.

9. The device as defined in claim 8 wherein: said pre-amp and automatic volume regulator has its output connected to a multiplicity of RC Phase Shift Audio Sine Wave Oscillators which act as tone separators when held just barely below oscillation.