Note: Descriptions are shown in the official language in which they were submitted.
10463~
Background of the Invention
This invention relates generally to electronic
musical instruments, and more particularly to electronic
organs and the like, wherein a multi-frequency generator is
used to generate a plurality of frequencies corresponding
to the plurality of frequencies associated with one octave
of a musical keyboard~ Musical frequencies of other octave,
either higher in frequency or lower in frequency, are
generated by multiplication or division of the base frequency
obtained from the multi-frequency generator.
Electronic organs have become relatively common
in the musical industry and provide means for simulating
the sounds produced from larger wind operated pipe organs
and the like. Such electronic organs differ from one
another substantially in certain specific respects, such as
whether the tone produced from the organ is obtained by a
tone generator associated with additive or subtractive cir-
cuits. They also differ as to the specific type of generator
used to obtain the base frequencies, as for example, whether
they are transistor or tube oscillators, wind-driven reed
elements, rotating tone wheels, and the like. ~owever, all
of these electronic organs can be distinguished by certain
common features. In particular, each organ has a plurality
of tone generators, there being one tone generator for each
note of the keyboards associated with a two-manual organ.
Furthermore, associated with the less expensive types of
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electronic organs there is a single tone generator as~ ciated
with the pedal tones, these tones being derived by one or
more divider circuits which divide the frequency from the
keyboard. However, only one pedal note at a time can be
played with this type of circuit so therefore, only one tone
generator is needed.
It will be immediately apparent that there is a
rather significant redundancy of tone generators used in
prior art types of electronic organs. However, since the
maximum number of notes that normally can be played at any
one time is twelve, one note for each finger of the two hands
and one note for each foot when manipulating the foot pedals,
there are a multitude of tone generators that are not in
use. In popular organ playing, it is unusual to use more
than one pedal tone at a time and it is to be expected that
no more than perhaps five notes will be played at any one
time by the fingers of both hands. Some effort has been
made to reduce the redundancy of tone generators needed by
using tunable oscillators, wherein an oscillator is shared
with two or three adjacent notes on the keyboard. This is
done under the presumption that only one of these notes
will be played at any one time. The presumption does not
always hold true however, and this is at best a low cost
approach to developing electronic musical instruments of
this type. However, there are still more tone generators
needed than can be utilized at any one time.
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In any event, the oscillator or other tone genera-
tors provide an audio frequency oscillation which bears a
direct relation to the frequency of the note being played.
In the case oE subtractive type organ circuits, the note
generated is the fundamental of the note played. In this
case a large number of harmonics are pro~ided by the genera-
tor, and the undesired harmonics are filtered out in accor-
dance with the organ stop then being used On the other
hand, in the case of additive organ circuits, the tone
gencrated may be a sub-harmonic of the tone played and
this sub-harmonic is then multiplied to achieve the desired
frequency.
All of the electronic organ circuitry heretofor
utilized have been of the type which require discrete
active and passive components formed in large chassis or
secured to large circuit boards, such as printed circuit
boards and the like. These discrete components may take
the form of individual tubes or transistors as well as
including inductance and capacitance elements which provide
the necessary LC circuits for the oscillators. This type
of prior art configuration and any of the above types of
organ arrangements is relatively expensive to manufacture,
and furthermore, requires a substantial amount of maintenance
over the life of the organ. As well as corrective and
preventative maintenance, occasional tuning of the oscil-
lator circuit is required to maintain the organ tone qualities
in tune. `-~
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104~311
Statement of the Invention
In accordance with the present Invention, in an
electronic musical instrument having a plurality of control
means operable to energize electro-acoustic transducer means,
there is provided the combination comprising: a large scale
integrated circuit chip having first circuit means for
developing a plurality of different audio frequencies to be
reproduced by said electro-acoustic transducer means, each
of said audio-frequencies being electronically developed in
response to actuation of an associated one of said plurality
of control means, second circuit means operatively coupled
with each of one of the plurality of control means for pro-
ducing a pulse output independently of said audio frequencies
as a result of the operation of each of said control means,
sald pulse outputs being available to energize other electronic
circuits assocl~ed with said electronic musical instrument.
Brief Description of the Drawin~s
In the accompanying drawings, whichillustrate an exem-
plary embodiment of the present Invention:
Fig. 1 is a simplified block diagram of an electronic
organ circuit utilizing large scale integrated circuit components
in accordance with the principles of this invention;
B - 5
1 0 ~ ~ 3 1 1
Fig. 2 illustrates one combination of elements to
form a frequency divider and sub-harmonic adding circuit which
is configurated in accordance with the principles of this
lnven~ion, and which form one group of components on the inte-
grated circuit chip of Fig. l;
Fig. 3 illustrates a modified form of the circuit
configuration of Fig. 2 which is used to obtain one single
note output therefrom, thereby allowing two independent
integrated circuit chips to be used, one integrated circuit
chip providing 18 tone outputs while the other integrated
circuit chip provides l9 tone outputs to provide a total of
37 tone outputs for a keyboard of the electronic organ;
Fig. 4 illustrates a circuit for controlling the
input circuits of Figs. 2 or 3 either with positive or negative
static signal information;
Fig. 5 is a circuit configuration which produces
pulse signal information corresponding to the actuation of a
key on the keyboard of Fig. 1, and which pulse signal infor-
mation may be used to initiate operation of a percussive sound
generating system;
Fig. 6 is an alternate form of frequency divider
circuit which can be formed on a single integrated circuit
chip in accordance with the principles of this invention,
and used to provide audio-frequency signal information for
an electronic organ;
Fig. 7 is an alternate circuit configuration of
Fig. 6, and which can be formed on the same integrated
circuit chip therewith;
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Fig. 8 is still another alternate circuit config-
uration which can be formed on the same integrated chip;
Fig. 9 is still another circuit configuration which
can be formed in accordance with this invention and formed on
the same integrated circuit chip as those illustrated in
Figs. 6, 7, and 8;
Fig. 10 is an alternate circuit configuration formed
in accordance with the principles of this invention and formed
on the same integrated circuit chip;
Fig. 11 is still another alternate configuration of
the circuit constructed in accordance with the principles of
this invention and formed on the same integrated circuit chip;
Fig. 12 is a simplified circuit configuration illus-
trating means for producing reset pulses for the various divider
networks illustrated herein;
Fig. 13 illustrates a control circuit for controlling
~he operation of various divider networks of Figs. 6-11 and 14
through 18;
Figs.14, 15, 16, 17, 18, and 19 illustrate additional
circuit configurations that are formed on the single large scale
integrated circuit chip to achieve other frequencies for the
electronic organ of this invention;
Figs. 6, 7, 8, 9, 10, 11, 14, 15, 16, 17, 18, and 19
are all on one integrated circuit as shown in Fig. 22: only
the MFG is external. This circuit added to two pair of the
circuits of Fig. 1 converts a dual 37 note keyboard into a dual
44 note keyboard.
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104f~311
Fig. 20 illustrates an OR gate and a plurality of
parallel connected shift registers and one-shot multivibrators
which can be formed on the integrated circuit chip which forms
the circuits of Figs. 6-19 (except for 12 and 13~, This cir-
cuit configuration produces pulse signal information corres-
p~nding to a key on the upper keyboard;
Fig. 21 illustrates still another circuit configura-
tion of an OR gate and shift register with series connected
one-shot multivibrators in accordance with the principles of
this invention, and this circuit produces pulse signal infor-
mation corresponding to a key from the lower keyboard; and
Fig. 22 is a partial circuit arrangement which shows
how the divider circuits are used to develop 7 notes for the
upper and 7 notes for the lower manuals of a two manual key-
board. Adding this circuit to two pair of circuits of Fig. 1
will convert a dual 37 note manual into a dual 44 note manual.
De,tailed_Description of the_Illustrated Embodiments
Referring now to Fig. 1 there is seen a simplified
block diagram of an electronic organ circuit constructed in
accordance with the principles of this invention and designated
generally by reference numeral 10. The electronic circuit 10
includes a multitude of manually operated key switches 11 so
arranged to have an electrical contactor thereof engage a bus
bar 12 positioned immediately adjacent thereto. The key
switches 11 represent the key on an organ keyboard. In the
illustrated embodiment, the bus bar 12 may have a positive or
negative voltage applied thereto, or it may be connected to a
ground potential, this depending on the type of circuit
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configuration being used. The particular configuration illus-
trated herein has the key switches 11 ranging from a high F to
a low F of a musical scale providing 37 separate key switches
for all of the natural and sharp notes associated with each
octave. While the key switches 12 of the keyboard are here
illustrated as being from F to F, it will be understood that
other arrangements may be from C to C.
The circuit configuration illustrated in Fig. 1 has
an oscillator circuit 14 which may operate at a frequency of
about 667 kHz. However, it will be understood that other fre-
quencies may be used for the master oscillator 14 illustrated
herein. The output of the master oscillator 14 is delivered
to a multi-frequency generator circuit 16 which has a plurality
of internally associated divider networks which are operated
by the single train of pulses delivered thereto from the oscil-
lator 14. Preferably, the multi-frequency generator has twelve
independent output frequencies produced thereby and are delivered
over a plurality of lines 17, 18, 19, 20, 21 and 22, which are
illustrated specifically and over a plurality of lines 23 indi-
cated collectively for purposes of simplification. The lines23 are connected to a plurality of circuits indicated in broken
lines near the bottom of the figure and which are the same as
those shown in solid line.
In accordance with the features of this invention,
the output lines from the multi-frequency generator 16 are
delivered to input circuits associated with an integrated
circuit component 24, preferably of the large scale integrated
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circuit type, referred to in the art as LSI devices. The LSI
device most advantageously utilized herein is obtained from
Wurlitzer Company, North Tonawanda, New York, under part number
141,097. However, it will be understood that other large-scale
integrated circuit chips may be utilized. The integrated circuit
24 has associated therewith a multitude of different subgroups
of circuitry which are formed from a selected plurality of
active and passive electronic components. For example, the
output line 17 from the multi-frequency generator 16 is delivered
to a tone developing divider circuit 26 which has input lines
27, 28 and 29 associated therewith. The tone developing divider
circuit also has nine output lines 44 shown going to audio-
amplifier 42. These signals may go through various filters.
By way of example, the frequency delivered by the tone divider
circuit is as follows: If key switch F is closed and this con-
trol signal goes through line 27 then the input frequency F
will be delivered on output 70 (Fig. 2) and the next octave
down (sub-harmonic) will be delivered on output 72 and the
next lower octave on output 74. Therefore, once the initial~ -
frequency is obtained for the first note to be generated for
the highest octave the sub-harmonic signals for the following
two octaves are automatically obtained by dividing, or multi-
plying, whicheverthe case may be, of the main frequency obtained
over the line 17.
The output line 18 of the multi-frequency generator
is delivered to a second divider circuit 30 which, in turn,
has three input lines 31, 32 and 33 connected to the E keys
of each of the three octaves illustrated. In similar fashion
a corresponding plurality of divider networks 36, 37, 38 and
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1 0~ 3 1 1
39 are provided and connected to the various other keys, as
for example, D sharp, D, C sharp and C. This, then, provides
means for generating notes for half of the notes of each
octave illustrated herein.
While there are nine outputs from each of the divi-
der circuits 26, 30, 36, 37, 38 and 39, they may be connected
in common to provide a total of nine output lines from the
chip 24.
A second integrated circuit unit 40 has a similarly
connected plurality of divider circuits associated therewith
to generate the other half of the octave and for generating a :
single note to provide the last F on the keyboard. Here the
interconnectiDn is illustrated just by partial broken lines
for purposes of clarity so as not to overcomplicate the line
drawings of the-figure. It will be understood, therefore, that
the circuit configuration of the second integrated circuit unit
40 is substantially identical to the circuit configuration of :~
the integrated circuit unit 24. Also, there may be nine output
lines from the chip 40. Therefore, the total number of outp~t
20 connections from the two chips 24 and 40 will be eighteen or :
again, if output frequency range can be allowed to go to one
octave then the nine outputs of 24 can be connected to the
nine outputs of 40 thus resulting in nine outputs. The large-
scale integrated circuit 40 includes a tone divider circuit 90 to
be described in detail hereinbelow.
Closure of the appropriate key switch ll will enable
a gating circuit to transfer signals within each of the divider . .
circuits illustrated so that the outputs thereof will be deliv- ¦ .
ered to voicing filters and an audio-amplifier stage 42, which,
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in turn, is connected to a loudspeaker device 43 to energize
the same. Again, for purposes of simplicity, output lines 44
are shown connected between the divider stage 39 and the audio-
amplifier 42, it being understood that the same output lines
are also associated between the dividers 26, 30, 36, 37 and 38.
The integrated circuit unit 24 provides means for
generating eighteen notes of the musical scale illustrated
while the integrated circuit 40 provides means for generating
nineteen of the notes illustrated. Therefore, a total of
thirty-seven musical key notes can be obtained by the circuit
configuration illustrated herein. Associated with the inte-
grated circuit units 24 and 40 are percussion key pulse output
circuits 46a and 46, respectively, which will sense the closure
of any one of the key switches 11 resulting in a pulse signal
output on line 47a or 47. This pulse signal will occur for
each new key switch closure. Lines 47a and 47 are connected in
common to percussion voicing filters and therefrom to audio
amplifier circuit 42 for generating suitable percussion accom-
paniment for the electronic musical instrument illustrated herein.
Output lines 47 or 47a can be connected to any suitable automatic
percussion rhythm device. For example, one such device which
can be utilized is disclosed in patent 3,585,891 issued to
Schwartz on June 22, 1971, and assigned to the same assignee
of record.
Turning now more specifically to Fig. 2, the divider
network 26 is illustrated herein in detail, it being understood
that all of the divider circuits 30, 36, 37, 38 and 39 associa-
ted with the electronic integrated circuit units 24 are construc-
ted substantially in the same manner except for those modifications
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1046311
specifically illustrated herein. Also, the divider circuits of
the integrated circuit chip 40 are constructed in the same manner.
The divider circuit 26 has an input terminal 50 which
delivers a first fundamental frequency of the note to be
developed to a flip-flop circuit 51 and NOR gate 52. The
circuit 26 is so arranged to be adapted for operation by
either negative D.C., i.e. zero logic or ground potential, or
positive D.C., i.e. plus one logic, applied to the terminal
FC. In the case of positive D.C. the signals are delivered
directly through the NOR gate 52 when the FC input is high and
FC input is low. This will produce an input signal to a NOR
gate 53 which, in turn, applied the first fundamental frequency
to the input of a NOR gate 54. The second input of NOR gate 54
is connected to the associated key switch through the line 27,
this being the associated F key of the key switch arrangement 11.
The pulse through NOR gate 53 is delivered to a flip-flop circuit
56 to produce the first sub-harmonic of the tone being generated.
The output of flip-flop 56 is also delivered to a second flip-
flop 57 to develop still another sub-harmonic. The output o
flip-flop 57 is delivered to a flip-flop circuit 58 which, in
turn, has its output delivered to a flip-flop circuit 59. There-
fore, the fundamental frequency at the output of NOR gate 53
is divided four times to provide four sub-harmonics thereof. The
output of flip-flop 56 is tied to the input of a pair of NOR
gates 60 and 61, while the output of flip-flop 57 is tied to -
three NOR gates 62, 63 and 64. The output of flip-flop 58 is
connected to a pair of NOR gates 66 and 67 while the output of
flip-flop circuit 59 is connected only to a single NOR gate 68.
It will be noted that the NOR gates associated with
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the outputs of the flip-flop circuits are arranged in groups
so that each key switch closure will turn on three octaves of
frequencies which can be called the fundamental and first and
second sub-harmonics or the fundamental and second and fourth
harmonics. For example, the fourth harmonic frequency of high
F is delivered to an output terminal 70 through fixed resistance
element 71. This occurs only when the key associated with
line 27 is actuated to enable the NOR gates 54, 60 and 62.
However, the second harmonic at the output of flip-flop 56
is also delivered through the second NOR gate 60 and this
signal is applied to a terminal 72 through a fixed resistor 73.
Finally, the fundamental for this particular note is
obtained from the output of flip-flop circuit 57 and delivered
through NOR gate 62 to a terminal 74 through a resistor 75.
When line 27 is activated by closure of the associated key
switch the audio signal information corresponding to the funda-
mental and the second and fourth harmonics are delivered to the
output terminals 74, 72 and 70 to be amplified within the audio-
amplifier stage 42, Fig. 1. The corresponding output terminals
of the divider circuits 30, 36, 37, 38 and 39 are preferably
connected to the same common output lines which are coupled to
the audio-amplifier 42.
The note for the next octave, therefore, has i1:s
fourth harmonic frequency developed at the output of flip-flop
56 and delivered to a terminal 76 through a fixed resistor 77, : -
and the NOR gate 61. The second harmonic of this second funda-
mental frequency is developed at the output of flip-flop 57
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1046311
and applied through NOR gate 63 to terminal 78 through a fixed
resistor 79. Finally, the fundamental of this second funda-
mental frequency, which is the middle range octave note, is
developed at the output of flip-flop 58 and is then delivered
through NOR gate 66 to output terminal 80 through its
associated series connected resistor. Therefore, the funda-
mental frequency of the note displaced one octave from the
note produced at output 74 has associated therewith its
corresponding second and fourth harmonics. -~
The fourth harmonic frequency for the similar note
associated with the next octave lower is, therefore, developed
at the outputs of flip-flop circuit 57 and is applied to a
terminal 81 through NOR gate 64 and its associated fixed resis-
tance element. The second harmonic of this note is developed
at the output of flip-flop circuit 58 and delivered to a terminal
82 through NOR gate 67 and its associated fixed resistors.
Finally, the fundamental is developed at the output of flip-
flop 59 and applied to a terminal 83 through NOR gate 68 and
its associated fixed resistor. Therefore, when the F note
20 of the middle octave is desired, that associated key switch is
closed to activate line 28 and enable the NOR gates 61, 63 and
66. On the other hand, if the F note of the next lowest octave
is desired, that associated key switch is closed and thereby
enabling line 29 and the associated NOR gates 64, 67 and 68.
Associated with the divider circuit 26 is an output signal
developed at line 85 which is used to develop a clock pulse
used in connection with providing a reset for all the dividers
1046311
of the integrated circuit. The reset is necessary to insure
proper phasing between the same frequencies of two keyboards.
In the preferred embodiment the resistance value of
the fixed resistance elements at the output of the NOR gates
is in the order of about 20,000 ohms with respect to the posi-
tive potential, it being understood that different resistance
values can be used for the respective different sub-harmonic
outputs associated therewith. Furthermore, it will be under-
stood that if the frequency control input FC is switched to a
ground potential, then all of the output frequencies will
drop one octave as a result of the extra flip-flop circuit 51
which adds one divide-by-two circuit in series with the other
flip-flops.
To achieve this broad range of control for input
signals of different logic levels, the integrated circuit 24
is provided with an inverter circuit 86 which has input signals
thereof received from the input line 87 to provide the inverted
signal, as best seen in Fig. 4. This input is also connected
to Bf through resistor 85. Therefore, with the FC potential
applied to one input of NOR gate 52 and the FC potential applied
to one input of a second NOR gate 88, Fig. 2, the necessary
modification is obtained without requiring components to be
added to the circuit after the circuit has been installed.
It will be noted that also connected to the terminals
70, 72, 74, 76, 78, 80, 8~ ~ a~ 83 are resistance elements indi-
cated in phantom line, which resistance elements correspond to
the audio-output circuits of the other divider networks 30,
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36, 37, 38 and 39 of the integrated circuit chip 24. Also, it
will be understood that the audio-output terminals of the
integrated circuit chip 40 may be connected in common with
the audio-output terminals of the integrated circuit chips 24
so that audio signals can be mixed together and amplified in
the usual manner. While phantom lines are not shown for
resistors of other divider circuits, it will be understood
that they ~ay be connected in the same manner as that of Fig. 2.
Referring now to Fig. 3 there is seen an alternate
modification of a divider circuit constructed in accordance
with the principles of this invention and which is also formed
as part of the large scale integrated circuit chip. In this
instance, however, the circuit configuration of Fig. 3 forms
the last divider circuit 90 of the integrated circuit chip 40
to provide the last note output of the tone developing cir~
cuits. Therefore, by obtaining eighteen outputs from six
frequency dividers associated with each of the integrated cir-
cuit chips and a single output from one of the frequency
dividers on a circuit chip, a total of thirty-seven notes can ~ -
be generated. It will be noted, however, that the circuit con~
figuration of Fig. 3 is also formed on the integrated circuit
chip 24 but is not used. Here the output signal from the multi~
frequency generator 16 is applied to a terminal 91 so that
pulse signal information can be delivered both to a first flip-
flop stage 92 and to a NOR gate 93. The output of flip~flop
92 is delivered to a second NOR gate 94 which, in turn, has
its output delivered to a NOR gate 96. The output of NOR gate
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93 is also connected to NOR gate 96. The function of flip-
flop circuit 92 and NOR gates 93, 94 and 96 is substantially
the same as that corresponding to similar components of Fig. 2.
The output of NOR gate 96 is delivered to a first
flip-flop circuit 97 which forms the first divider for a series
of dividers. The output of flip-flop 97 is delivered to a
flip-flop 98 which, in turn, has its output signal delivered
to a flip-flop circuit 99. The output of flip-flop circuit 99
is delivered to a flip-flop circuit 100 and to a NOR gate 101.
The output of flip-flop circuit 100 is delivered to a final
flip-flop circuit 102 and to a second NOR gate 103. The out-
put of flip-flop circuit 102 is then delivered to a NOR gate
104. In this instance, the fourth harmonic frequency is that
obtained from the output of flip-flop circuit 99 and delivered
through NOR gate 101 when the associated key switch is
depressed to energize the enabling line 106 associated with
one of the inputs of the NOR gates 101, 103 and 104. The
second harmonic is obtained from the output of flip-flop 100
which passes through NOR gate 103. Finally, the fundamental
is obtained from the output of flip-flop 102 as delivered
through NOR gate 104. In similar fashion, the output of the
NOR gates lOl, 103 and 104 are provided with resistance ele-
ments 107, 108 and 109, respectively, to deliver the appropriate
signals to the same output terminals 81, 82 and 83.of Fig. 2.
The appropriate key switch is connected to the input terminal
113 which enables the NOR gates 101, 103 and 104 to effect a
transfer of the signals from the divider circuit 90 to the
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appropriate audio-amplifier and output stages. These outputs
can also be called footages instead of fundamental and second
and fourth harmonics. The footages can be any three consecutive
octavely related footages such as 16', 8' and 4' or 5 1/3',
2 2/3' and 1 1/3', etc.
Referring now to Fig. 5, there is seen a pulse output
circuit also associated with the integrated circuit chip upon
which is formed the plurality of divider circuits of ~ig. 2 and
Fig. 3. The pulse output circuit is used to produce a control
output signal which is responsive to the actuation of any one
of the keys on the keyboard and which pulse output signal is
delivered to a percussion control circuit. The circuit arrange-
ment of Fig. 5 corresponds to either the percussion key pulse
outlet 46 or the percussion key pulse outlet 46a, of Fig. 1. Out-
put terminal 139, therefore, corresponds to either the output
line 47 or 47a of Fig. 1. Therefore, by utilization of this
pulse output signal to control the operation of a percussive
circuit arrangement a percussion organ sound can be obtained to
accompany the playing of the electronic organ of this invention.
To achieve this particular result, each one of the keys associated
with the lines 27, 28, 29, etc. are also connected to a reset
input line associated with a shift register circuit. For example,
the line 27 is associated with a shift re~ister circuit 120 which
also has connected thereto a clock pulse line 121. When the key
switch associated with line 27 is closed, an output D.C. voltage
change will occur on the outputline 140. ThisoutputD.C. voltage
change is delivered to a one-shotcircuit 122 which, in turn, converts
this D.C. voltage change into a short pulse. The shift register
circuits are used to eliminate any problems resulting from key
switch bounce. The key switch bounce occurring on key closure
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and again on key opening results in only the one desired pulse
occurring on key closure. After the output D.C. voltage change
on line 140 due to the key switch closure on line 27, the vol-
tage will not change back on key switch opening (or key switch
bounce) until two clock pulses on line 121 shift in the opposite
D.C. level. This means that line 27 will have to have a "clean"
key open signal for two slow clock pulses CL before the output
on line 140 resets to allow for another key closure signal pulse.
The output of the one-shot c irc uit 122 is delivered to one of
lO the inputs of a nineteen input OR gate circ uit 123 which, in
turn, has its output circuit connected to the input of a pair
of flip-flop circuits 124 and 126.
Similarly, the line 28 associated with th e next key
of the divider circuit 26 is delivered to an input of a shift
register 127 which also has a clock pulse line 128 associated
therewith. The output of the shift register 127 is coupled
to a one-shot circuit 129 in the same manner as that of the
shift register 120. The output of the one-shot circuit 129
is coupled to another one of the inputs of the nineteen-input
20 OR gate circuit 123. Therefore, regardless of what key on
the keyboard is actuated to achieve the desired note to be
played, each and every actuation of the keys will cause an
output pulse to be generated by the pulse output circuit of
Fig. 5. The timing pulse clock CL is obtained from the input
clock ICL at the terminal 130. This clock ICL passes through
a divide-by-eight circuit 131 which then produces the clock
pulse CL used for the shift registers above and is also at one
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input of an AND gate 132. The output of the divider circuits
124 and 126 are c~upled to a NAND gate 137 which, in turn, has
its output coupled to the input of an amplifier stage 138 to
produce the pulse signal output at a terminal 139. The output
of NAND gate 137 is also coupled to the second input of AND
gate 132. The amplifier stage 138 is preferably a single ended
tran~istor which turns on to B~ when the input is at a "1" or
B~ level. When a pulse passes through OR gate 123 the pulse
resets dividers 124 and 126. The two divider outputs go to 0
and thus the output of gate 137 goes to a one level turning on
output 139 and allowing the clock CL to pass through gate 132
to the input of divider 124. After three counts of clock CL
both outputs of the dividers will be at a one level resulting
in a 0 level at the output of gate 137 thus turning off the
output at 139 and turning off the clock CL from the input of
divider 124. The signal remains off until the next reset pulse
occurring from OR gate 123 which occurs each time a key switch
is actuated. This output signal at terminal 139 turns on for
an equivalent of seventeen to twenty-four counts of the input
frequency ICL thus determining the output pulse width.
The clock pulse at the terminal 130 is also deli~ered
to a shift register circuit 133 which, in turn, has a divide-
by-four circuit 134 connected to the clock input thereof. The
divide-by-four circuit 134 has the input terminal 136 thereof
associated with the output line 85 of the divider circuit shown
in Fig. 2. Therefore, this particular pulse repetition rate is
substantially reduced as compared to that of the input to terminal
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130. If when the electronic organ is first turned "on" the
ICL input at 130 is held off long enough to obtain two clock
pulses from divider 134 then the output of shift register 133
will turn on the divider reset signal RD. This will reset all
dividers shown in Fig. 2 and 3 and divider blocks 26, 30, 36,
37, 38, 39 and 90 as shown in Fig. 1. When ICL is allowed to
start shift register 133 will reset turning off RD. Thus, all
dividers will start in the same state at the same time so any
two outputs of the same frequency between two keyboards will
always be in phase.
Referring now to Figs. 6, 7, ~, 9, 10, 11, 14, 15,
16, 17 and 18 there is seen a plurality of tone developing
circuits formed of divider networks associated with a single
integrated circuit component, such as a large scale integrated
circuit (LSI). These circuits as well as the circuits shown in
Figs. 12, 13, 19, 20 and 21 are all formed on a single LSI. In
this instance there are only two audio-output groups of signals
associated with each divider network. The particular circuit
configuration illustrated herein allows for circuit modification
of the thirty-seven position keyboard so that addition of just
one integrated circuit will extend two thirty-seven position
keyboards to two forty-four note keyboards The frequency to
be divided is applied to an input terminal 140 which may form
the fundamental frequency of one output signal and which is also
applied to the inputs of NOR gates 141 and 149. The frequency
from terminal 140 is divided by a flip-flop circuit 142 and
applied to the output terminal thereof where it is delivered to
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.
--- 1046;~11
a pair of NOR gates 143 and 144. Also, the output of flip- -
flop 142 is delivered to a flip-flop 146 which, in turn, has its
output associated with a pair of NOR gates 147 and 148. It will
be noted that the frequency output from the output terminals
151, 152 and 153 are substantially the same as the frequency
output from terminals 154, 155 and 156. However, the key used
to actuate the NOR gates associated with these output terminals
is different. For example, the key switch associated with
NOR gates 141, 143 and 147 may be connected to a terminal 160,
which may be associated with one of the upper manual key switches
while the key switch associated with NOR gates 149, 144 and 148
may be associated with a terminal 161 which, in turn, is connected
to an OR gate 162. The other input of OR gate 162 is associated
with a lower manual key switch input. The integrated circuit
chip upon which the circuits of Figs. 6-22 are formed will have
as many as seven upper and seven lower manual switch inputs and
associated pulse circuitry to convert two 37 note keyboards to
two 44 note keyboards.
Fig. 7 illustrates still another type of divider
network which is formed of the single integrated circuit chip.
Here the input frequency is applied to a terminal 166 while
the key switch input terminals are designated by reference
numerals 167 and 168. The input frequency at terminal 166 is
delivered to a divider flip-flop 169 and to a pair of NOR
gates 170 and 171. The output of flip-flop 169 is delivered
to a pair of NOR gates 172 and 173 and to the input of a
second flip-flop circuit 174. The output of flip-flop circuit
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174 is delivered to the NOR gates 176 and 177. The NOR gates
170, 172 and 176 are enabled by actuation of a key associated
with terminal 169. This will apply the fundamental and two
(or three footage frequencies) harmonic frequencies of the
audio signal to the output terminals 153, 152 and 151. On the
other hand, NOR gates 171, 173 and 177 are enabled as a result
of actuation of a key associated with terminal 168, which, in
turn, passes through an OR gate 181 This will cause the audio-
frequency signal which is generated to be delivered to the output
terminals 154, 155 and 156. Here again, it will be noted that
the outputs of the NOR gates are delivered to the output termi-
nals through a passive resistance element associated with the
integrated circuit. Preferably the resistance value of all
of the resistors is the same, this being in the order of about
20,000 ohms.
Referring now to Fig. 8 there is seen still another
divider network constructed in accordance with this invention
and formed on the same integrated circuit chip. Here the
input frequency is applied to a terminal 186 while the key
switches are connected to key terminals 187 and 188. The fre-
quency at terminal 186 is applied to NOR gates 189 and 190 and
to the input of a flip-flop circuit 191. The output of flip-
flop circuit 191 is connected to a second flip-flop 192 and to
a pair of NOR gates 193 and 194. In like fashion, the output
of flip-flop circuit 192 is applied to NOR gates 196 and 197.
The NOR gates 189, 193 and 196 are enabled as a result of
actuation of the key associated with terminal 187, which in
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turn, allows the audio-frequency signals thus developed to be
applied to the output terminals 151, 152, and 153. This signal
is delivered through associated series connected output resistors
201, 202 and 203. The NOR gates 190, 194 and 197 are enabled
as a result of actuation of the key associated with terminal
188 to provide transfer of the audio signal thus developed to
output terminals 154, 155 and 156. Here again, the output
frequency signals are applied through associated series connected
resistors 208, 209 and 210, respectively. The NOR gates 190,
194 and 197 have their enabling lines connected to the output
of an OR gate 211.
Referring now to Fig. 9 there is seen still another
frequency divider circuit formed on the integrated circuit
chip constructed in accordance with this invention. In this
instance the fundamental frequency is applied to a terminal
214 while the key switch enabling signals are applied to terminals
215 and 216. The output signal from terminal 214 is applied to
a pair of NOR gates 218 and 219 and to the input terminal of a
flip-flop circuit 220. The output of flip-flop circuit 220
is applied to a second flip-flop circuit 221 and to a pair of
NOR gates 222 and 223. The output of flip-flop circuit 221 is
also applied to a pair of NOR gates 224 and 226. The NOR ga~es
218, 222 and 224 when enabled, apply output signals to terminals
151, 152 and 153 through their associated series connected
resistors 230, 231 and 232, respectively. When NOR gates 21g,
223 and 226 are enabled, as a result of actuation of the key
associated with terminal 216, output signals are applied to output
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terminals 154, 155 and 156 through their respective series con-
nected resistors 236, 237 and 238. The terminal 216 is connected
to the enabling line of NOR gates 219, 223 and 226 through an
OR gate 236.
Referring now to Fig. 10 there is seen still another
divider circuit constructed in accordance with the principles
of this invention and which is formed as part of the single
integrated circuit chip upon which the divider circuits of
Figs. 6, 7, 8 and 9 are formed, Here the input frequency is
applied to a terminal 237 while the key actuated switches are
connected to terminals 238, 239 and 161. The terminal 237
applies a fundamental frequency to a pair of NOR gates 240
and 241 and to a flip-flop circuit 242, The first sub-harmonic
is generated at the output of flip-flop circuit 242 and applied
to NOR gates 243 and 244, and to the input of a second flip- ;
flop circuit 246. A second sub-harmonic is generated at the
output of flip-flop circuit 246 and applied to a pair of NOR
gates 247 and 248. The NOR gates 240, 243 and 247 are enabled
as a result of actuation of the key associated with the terminal
238 and thereby applies an output audio signal to terminals 151,
152 and 153 through their associated resistors 253, 254 and 255,
respectively. NOR gates 241, 244 and 248 are enabled as a
result of actuation of the key associated with terminal 239
or 161 depending on control KC thereby applying an output signal
to terminals 154, lS5 and 156 through their associated connected
series resistors 260, 261 and 262. It will be noted that in
this instance the enabling line associated with terminal 239
and 161 includes three NOR gates 257, 258 and 259.
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~04631~
If the KC signal is high and the KC signal low then
the output of NOK gate 257 line 250 will always be a low level
thus allowing the key switch input 161 to control NOR gates
241, 244 and 248. Meanwhile in Fig. 6 this same key switch
input 161 does not control NOR gates 149, 144 and 148 because
this same KC input high does not allow the key switch signal to
pass through OR gate 162. If the KC control input was low and
KC was high then key switch input 161 would control NOR gates
149, 144 and 148 in Fig. 6 and only key switch input 239
controls NOR gates 241, 244 and 248 of Fig. 10. Thus when KC
is low the lower manual key switches control the same seven
groups of frequencies as the upper manual. In this case both
keyboards have no stagger or the lower keyboard can have a
12 note (one octave) stagger however the lower manual funda-
mental or footages are one octave higher than the upper key-
board. If the KC input is high then all frequencies for the
lower keyboard are shifted up four notes, thus allowing for an
eight note keyboard stagger with the lower ~eyboard footages
being one octave higher.
Referring now to Fig. 11 there is seen still another
divider circuit constructed in accordance with this invention
on a single integrated circuit chip. Here the input frequency
is applied to a terminal 263 while key actuated signal infor-
mation is applied to terminals 264 and 266 or 168. The signal
information applied to terminal 263 is applied to a pair of
NOR gates 267 and 268 and to a flip-flop circuit 269, The
second harmonic is developed at the output of flip-flop 269
1046311
and delivered to a pair of NOR gates 270 and 271 and to the
input of a second flip-flop circuit 272. The output of flip-
flop circuit 272 generates the fundamental and is applied to
a pair of NOR gates 273 and 274. The NOR gates 267, 270 and
273 are enabled as a result of actuation of the key associated
with terminal 264, thereby allowing transfer of the audio-
signal information from the NOR gates to output terminals 151,
152 and 153 through their associated series connected resistors
279, 280 and 281, respectively. The output of NOR gates 268,
271 and 274 is obtained as a result of actuation of the key
associated with terminal 266 or 168, thereby allowing transfer
of the audio-signal information to output terminals 154, 155
and 156 ~hrough their respective series connected resistors
286, 287 and 288. The KC and KC inputs controls which of the
key switch inputs 266 or 168 controls the three outputs above.
Fig. 14 illustrates still another divider network
constructed in accordance with this invention and associated
with the single integrated circuit chip. Here an input fourth
harmonic frequency is applied to terminal 290 while key actuation
is sensed at terminals 291 and 292 or 188. The frequency
applied to terminal 290 is delivered to a pair of NOR gates
293 and 294 and to the input of a flip-flop circuit 295. The
second harmonic is generated at the output of flip-flop circuit
295 and applied to a pair of NOR gates 296 and 297 and to the
input of a flip-flop circuit 298. The ~undamental frequency is
generated at the output of flip-flop 298 and is applied to NOR
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gates 299 and 300. When NOR gates 293, 296 and 299 are enabled
as a result of actuation of the key associated with terminal 291,
the output signal from the voltage divider network is applied
to terminals 151, 152 and 153 through their associated series
connected resistors 304, 305 and 306, respectively. When the
key associated with terminal 292 or 188 is actuated, NOR gates
294, 297 and 300 are enabled to deliver to output terminals
154, 155 and 156 the audio-signals thus developed. In similar
fashion, the audio-signals are delivered to these output termi-
nals through their series connected resistors 310, 311 and 312,respectively. Again 292 controls these outputs if KC is low and
key switch 188 controls these outputs if KC is high.
Referring now to Fig. 15 there is seen a somewhat
simplified divider network constructed in accordance with
the principles of this invention and which is formed as part
of the single integrated circuit chip associated with the
divider circuits of Figs. 6-11 and 14. Here the input
frequency is applied to a terminal 313 while the key switch
is associated with the terminal 216 from Fig. 9. The frequency
at terminal 313 is applied to a NOR gate 316 and to the input
of a flip-flop circuit 317. The second harmonic is generated
at the output of flip-flop circuit 317 and applied to a NOR
gate 318 and to the input of a flip-flop circuit 319, The
second sub-harmonic is generated at the output of flip-flop
circuit 319 and applied to a NOR gate 320. The NOR gates 316,
318 and 320 are enabled as a result of a signal delivered
through an OR gate 321 when the key associated with terminals
216 is actuated and KC input is low. The outputs of NOR gates
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1046311
316, 318 and 320 are applied to terminals 154, 155 and 156
through their series connected resistors 325, 326, and 327,
respectively.
Referring now to Fig. 16 there is seen another
divider circuit constructed in accordance with this invention
and ~orms part of the same integrated circuit chip as that of
Fig. 15. Here the input frequency is applied to a terminal
330 while the key actuated switch is associated with a termi-
nal 239 of Fig. 10. The frequency delivered to terminal 330
is applied to a NOR gate 332 and to the input of a flip-flop
circuit 333. The second harmonic is developed at the output of
flip-flop 333 and applied to a NOR gate 334 and to the input of
a second flip-flop circuit 336. The fundamental developed at
the output of flip-flop circuit 336 is applied to a NOR gate
337. The NOR gates 332, 334 and 337 are enabled as a result
of the output signals developed at OR gate 338 which, in turn,
allows the audio signal frequency to be transferred through
the NOR gates to the output terminals 154, 155 and 156. This
transfer of audio signal information takes place through the
20 series connected resistors 342, 343 and 344, respectively
whenever key switch 239 is actuated and KC is low.
Referring now to Fig. 17 there is seen a divider
circuit constructed in accordance with the principles of this
invention and which is formed within the same integrated cir-
cuit chip as the circuits illustrated in Figs. 6-11 and 14-
16. Here the input frequency is applied to a terminal 348
while a key switch is connected to the terminal 266 of Fig. 11.
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- - - . . . . - . - :
-- 10~}6311
The key switch is associated with one input of an OR gate 350
which, in turn, has the other input thereof arranged for connection
to the control input KC along line 351. The frequency applied
to terminal 348 is applied to a NOR gate 352 and to an input
o~ flip-flop circuit 353. The output of flip-flop circuit 353
produces the second harmonic which, in turn, is applied to a
NOR gate 354 and to the input of a second flip-flop circuit
356. The output of flip-flop circuit 356 is applied to a
NOR gate 357. Each of the NOR gates 352, 354 and 357 are
connected to output terminals 154, 155 and 156, respectively,
through their associated series connected resistance elements
361, 362 and 363.
Referring now to Fig. 18 there is seen still another
circuit configuration of a divider network which is formed as
part of the integrated circuit chip of this invention. Here
the base frequency is applied to a terminal 366 while the key
signal is applied to terminal 292 of Fig. 14 which, in turn,
is associated with one input of an OR gate 368. The NOR gate
368 provides an enabling signal to the inputs of the NOR
transfer gates 370, 371 and 372. The base frequency at terminal
366 is applied to NOR gate 370 and to a flip-flop circuit 373
which, in turn, generates the second harmonic to be delivered
to the NOR gate 371. Also the output of flip-flop circuit 373
is applied to the input of flip-flop circuit 374 which, in turn,
has its output connected to NOR gate 372. The signals developed
through the NOR ~ates 370, 371 and 372 are applied to output
terminals 154, 155 and 156 through their associated series
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~ 0~6311
connected resistors 379, 380 and 381, respectively. This cir-
cuit also provides one-half of the input frequency (of high E
at terminal 366) at output terminal 375.
Fig. 19 illustrates but a single divider network
which is a divide-by-two flip-flop circuit 384 having an input
terminal 386 and an output terminal 387. A reset line is
indicated at 388 and receives a reset signal to reset the
flip-flop. It will be noted that in all of the other figures
the reset line RD is used to reset the flip-flop of each of
the divider circuits. This circuit provides one-half the
frequency of the F note.
It will be understood that the resistance value of
all of the output resistors is the same and preferably in the
order of about 20,000 ohms.
Fig. 12 illustrates the dual stage shift register
as in Fig. 5 which can be used to generate the reset signal RD
used for resetting all dividers in this LSI circuit. The shift
register includes an input line 178 which receives the fre-
quency output of Fig. 6. This goes through a divide-by-four
block 390 resulting in a shift register clock signal of input
140 divided-by-sixteen. A voltage is applied to a line 391
to represent a logic-one level. A reset line 393 is applied
to the shift register 389 and is used to reset the shift register
to a logic-zero level when a reset pulse of a logic-one level is
applied thereto. If this input 393 is held off long enough to
obtain 32 counts of input 140 then reset line RD will go to a
one level resetting all dividers in this chip.
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104tj~11
Fig. 13 illustrates means for obtaining the D.C
control signal of one polarity and a similar D.C. control sig-
nal o~ an opposite polarity, these control signals being desig-
nated by KC and KC. The KC pulse is developed at the output of
an inverter circuit 394 and operates substantially in the same
manner as the circuit illustrated in Fig. 4. The inverter
circuit has its input connected to the Bf potential through
resistor 395. For example, the KC output of the circuit of
Fig. 13 is applied to the second input line of OR gates 162,
181, 211 and 236 and NOR gates 257, 277 and 301 of Figs. 6, 7,
8, 9, 10, 11 and 14, respectively. On the other hand, the KC
signal is applied to the second input of OR gates 321, 338, 350
and 368 of Figs. 15, 16, 17 and 18, and NOR gates 258, 276 and
302 of Figs. 10, 11 and 14, respectively. This circuit is formed
as part of the large scale integrated circuit chip.
ReEerring now to Fig. 20 there is seen a circuit which
will produce a pulse output, similar to that shown in Fig. 5,
but which pulse output will be responsive to actuation of key
switches associated with terminals 160, 167, 187, 215, 238,
264 and 291. On the other hand, the circuit configuration
shown in Fig. 21 is used to develop pulse signals corresponding
to the actuation of keys associated with terminals 161~ 168,
188, 216, 239, 266 and 292. The pulse output circuit of Fig.
20 is designated generally by reference numeral 400 and includes
a plurality of shift registers 401, 402, 403, 404, 405, 406 and
407. The shift registers 401-407 each have an input line from
the key switch inputs 160, 167, 187, 215, 238, 264 and 291,
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respectively. The clock pulse for the shift registers
is applied to the line 416 going to all the shift registers
of Fig. 20 and 21. The output of each of the shift registers
upon key closure is a D,C. voltage change and therefore is
applied to an associated one-shot multivibrator circuit 430,
431, 432, 433, 434, 435 and 436. The output of the one-shot
multivibrator circuits 430-436 is a short pulse delivered to
a seven-input OR gate 440 which, in turn, has its output
coupled to an appropriate circuit to develop the necessary
pulse output for operation of such things as percussion cir-
cuits. This additional circuit is the same as shown by blocks
124, 126, 130, 131, 137, 138 and 139 of Fig. 5.
Finally, the pulse output circuit of Fig. 21 is sub-
stantially the same as that of Fig. 20 but used to cooperate
with the lower manual key switch inputs. Here a plurality
of shift registers 501-507 are associated with the circuit
500 and in like manner have their corresponding key operated
switch lines 161, 168, 188, 216, 239, 266 and 292 associated
therewith and the same clock pulse line 416. The output of
the shift registers 501-507 is delivered to one-shot multi-
vibrators 530-536. The output of the one-shot multivibrators
530-536 is delivered to a seven-input OR gate 540 and operates
substantially in the same manner as the seven-input OR gate
440 of Fig. 20, The circuit configurations illustrated in
Figs. 20 and 21 are formed on the same integrated circuit chip
as the circuit configuration associated with Figs. 6-19.
It will be understood that in all of the circuit
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104631~
arrangements illustrated abovey the NOR gate circuits associ-
ated with the dividers may be AND gate circuits.
Fig. 22 illustrates a circuit arrangement which utilizes
the divider circuits of Figs. 6, 7, 8, 9, 10, ll, 14, 15, 16,
17, 18 and 19 to generate some of the notes required of the upper
and lower keyboards of a two manual organ. The multi-frequency
generator 16 has an F sharp note frequency connected to the
c ircuit of Fig. 6 over a line 601 to the input terminal 140.
A key switch line 160 is connected to the F sharp note key of
the upper manual key switch arrangement so that three footages
of the F sharp note generated within the c irc uit arrangement
of Fig. 6 is applied to the audio output lines 151, 152 and
153~ The F sharp frequencies for the lower manual keyboard of
the organ is obtained when the key switch 161 is closed through
the OR gate circuit 162 when the KC control input is low. The
F sharp key switch of the lower manual keyboard is also con-
nected to one input of a NOR gate 258 associated with the
divider circuit of Fig. 10. The F sbarp key switch is an A
sharp key switch if KC is high and the frequencies of Fig. 10
(A sharp) are actuated through NOR gates 258 and 259. A G note
frequency is obtained from the multi-frequency generator 16
over a line 602 and applied to the divider circuit illustrated
by Fig. 7. This G note frequency is applied to the audio output
circuits 151, 152 and 153 w~en the upper manual G switch is
closed and to the audio outputs 154, 155 and 156 when the lower
manual G switch is closed and KC is low. Again, it will be
noted that the lower manual G switch is connected to the divider
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_, . - -
1046311
circuit of Fig. 7 through an OR gate 181. The A note frequency
obtained from the multi-frequency generator 16 is applied to
the circuit arrangement of Fig. 9 over a line 603. Actuation
of either the upper manual or lower manual A key switches will
produce audio outputs. The lower manual key switch is connected
to the divider circuit of Fig. 9 thraugh an OR gate 236. The
A sharp output from the multi-frequency generator is delivered
over a line 604 to the divider circuit of Fig. 10. The divider
circuit of Fig. 10 will produce outputs when either of the A
sharp keys of the upper and/or lower keyboards is actuated.
The key associated with the lower manual is connected to the cir-
cuit of Fig. 10 through a pair of series connected NOR gates
257 and 259.
The B note frequency is delivered over line 606. The
C note frequency from the multi-frequency generator is delivered
over a line 607 to the divider circuit of Fig. 12 and produces
an output when either of the C note keys of the upper and lower
manual are actuated. The C note key of the upper manual is
connected to the divider of Fig. 12 directly over a line 291
while the C note key of the lower manual is connected to the
divider of Fig. 12 over a line 292 and a pair of series connec-
ted NOR gates 301 and 303 when KC is low and over line 188 and
through gates 302 and 303 if KC is high. The C sharp note fre-
quency from the multi-frequency generator 16 is delivered to the
divider circuit of Fig. 15 over a line 608 and to the inputs of
the audio-amplifier when the C sharp key of the lower manual
is actuated and KC is high.
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1046311
However, the output of Fig. 15 is also produced when the A key
¦ which becomes the C sharp key of the lower manual is actuated
as this key is connected to the divider circuit over a line
216 through an OR gate 321. This is when the KC control input
is high
I The multi-frequency generator 16 applies an E note
¦ frequency to the divider of Fig. 18 and this frequency is
divided in half and delivered over a line 613 to the E note of
the next lower octave. The divider circuit of Fig. 18 is also
connected to the C key of the lower manual keyboard over a line
292 and OR gate 368. Finally, the F note frequency from the
multi-frequency generator 16 is applied to the circuit arrange-
ment of Flg. 19 over a line 612 and this circuit produces the
lower octave F note over a line 614. As mentioned above, Figs.
18 and 19 produce the base frequency divided by one-half at
terminals 375 and 387, respectively
I Accordingly, the present invention provides an inte-
¦ grated circuit construction which has a multitude of divider
i circuits and pulse circuits incorporated therein to obtain a
plurality of audio-signal frequencies which are of a character
having the fundamental frequency and at least two sub-harmonics
associated therewith to produce a desired audio-tone for the
electronic organ. By so providing the electronic organ of this
type with integrated circuit configurations as those illustrated
herein, a substantially improved organ structure is obtained
while greatly reducing the cost thereof. While several specific
circuit configurations have been illustrated herein, it will be
1046311
understood that a multitude of other circuit configurations can
be incorporated without departing from the spirit and scope of
the novel concepts disclosed and claimed herein.
. .
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