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US3701040A Expired / Lapsed US ⏱️ 0.0 years remaining

Electronic musical instrument master oscillator with provision for frequency control

Assignee: Marmon Co
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Filing: 1971-01-11
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Granted: 1972-10-24
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Expires: 1991-01-11
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Abstract

Abstract A master oscillator operating in the MHz range for supplying a signal suitable for providing the notes of the musical scale, the various note signals being arrived at by frequency division of the master frequency. The oscillator has a high order of frequency stability together with ease of control for shifting the frequency to supply vibrato, portamento, trill, transposition features and the like. Control is exercised by incorporating a voltage-variable capacitance diode, ''''Varicap,'''' as an effective element in the oscillator tank and varying the diode bias. Features provide for isolation of the bias voltage from the main tank circuit, a zero-bias condition at the true frequency, and a novel comparison tuning system using a slightly off-pitch tuning reference standard for obtaining true pitch.

Inventors

  • 👤 Alexander J Borrevik
  • 👤 Charles J Tennes

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 16:21
CPC Classifications
G; G10; G10H; G10H1/00; G10H1/02; G10H1/04; G10H1/043; H; H03; H03B; H03B5/00; H03B5/08; H03B5/12; H03B5/1203; H03B5/1231; H03B5/1237; H03B5/124; H03B5/1243; H03B5/1256; H03B2200/00; H03B2200/003; H03B2200/0034; H03B2200/004; H03B2200/006; H03B2200/0092; H03B2201/00; H03B2201/02; H03B2201/0208; Y; Y10; Y10S; Y10S84/00; Y10S84/11

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 78 words
The method of tuning an oscillator having a resonant circuit to a selected frequency comprising providing a reference frequency slightly different from said selected frequency, temporarily changing the effective value of a component of said resonant circuit to shift the frequency of said oscillator by an amount equivalent to the differential between said selected frequency and said reference frequency, tuning said oscillator to said reference frequency and subsequently restoring the component temporarily changed to its original effective value.
Claim 2
Independent Claim 78 words
The method of tuning an oscillator having a resonant circuit to a selected frequency comprising providing a reference frequency slightly different from said selected frequency, temporarily changing the effective value of a component of said resonant circuit to shift the frequency of said oscillator by an amount equivalent to the differential between said selected frequency and said reference frequency, tuning said oscillator to said reference frequency and subsequently restoring the component temporarily changed to its original effective value.
Claim 3
Independent Claim 114 words
A system for providing the signals for the notes for a high octave of the musical scale comprising means providing an oscillator operating at substantially a nominal frequency of 2.75968 MHz, means providing twelve divider chains connected for dividing said frequency to provide the twelve notes of said octave, the 12 dividers for said 12 chains being adapted to divide by 349, 370, 392, 415, 440, 466, 494, 523, 554, 587, 622 and 659, and means for shifting the frequency of oscillation of said oscillator by an amount of the order of one to two per cent above and below said nominal frequency at a rate of the order of 6 to 7 Hz.
Claim 4
Independent Claim 114 words
A system for providing the signals for the notes for a high octave of the musical scale comprising means providing an oscillator operating at substantially a nominal frequency of 2.75968 MHz, means providing twelve divider chains connected for dividing said frequency to provide the twelve notes of said octave, the 12 dividers for said 12 chains being adapted to divide by 349, 370, 392, 415, 440, 466, 494, 523, 554, 587, 622 and 659, and means for shifting the frequency of oscillation of said oscillator by an amount of the order of one to two per cent above and below said nominal frequency at a rate of the order of 6 to 7 Hz.
Claim 5
Independent Claim 109 words
A system for providing the signals for the notes for a high octave of the musical scale comprising means providing an oscillator operating in the low megahertz range, means providing twelve divider chains connected for dividing said frequency to provide the twelve notes of said octave, means responsive to a variable voltage for shifting the frequency of oscillation of said oscillator to provide musical effects dependent upon pitch variation, means for supplying a variable voltage to said voltage responsive means to change the pitch of all said notes simultaneously, and the variable voltage supply means including means for varying said voltage on a cyclical basis at a vibrato frequency.
Claim 6
Independent Claim 109 words
A system for providing the signals for the notes for a high octave of the musical scale comprising means providing an oscillator operating in the low megahertz range, means providing twelve divider chains connected for dividing said frequency to provide the twelve notes of said octave, means responsive to a variable voltage for shifting the frequency of oscillation of said oscillator to provide musical effects dependent upon pitch variation, means for supplying a variable voltage to said voltage responsive means to change the pitch of all said notes simultaneously, and the variable voltage supply means including means for varying said voltage on a cyclical basis at a vibrato frequency.
Claim 7
Dependent Claim 236 words
An oscillator having a resonant circuit including a main capacitance element, a voltage-variable-capacitance diode effectively coupled with said main capacitance element, said voltage-variable-capacitance diode being adapted to vary the capacity in said resonant circuit and hence the oscillator frequency depending upon the value of a potential applied to said diode, means for applying a variable control voltage to said diode, means for applying the signal output of the oscillator to said diode at a level such that rectification of said signal by said diode occurs and produces a D.C. potential equivalent sufficient to bias said diode to a level where said diode capacity variation with voltage variation is substantially a linear function throughout a substantial portion of the range of voltage variation of said control voltage, means for tuning said oscillator to a selected frequency under conditions where said control voltage is zero, said tuning means including a source of reference frequency slightly different from said selected frequency, means for temporarily applying an appropriate potential to said diode to alter the capacity of said diode to shift the frequency of the oscillator an amount equivalent to substantially the difference between said selected frequency and said reference frequency, means for tuning to the reference frequency with the last said potential temporarily applied, subsequent removal of the tempoRary potential shifting the capacity of said diode and the frequency of the tuned oscillator by the amount of said difference.
Claim 8
Dependent Claim 236 words
An oscillator having a resonant circuit including a main capacitance element, a voltage-variable-capacitance diode effectively coupled with said main capacitance element, said voltage-variable-capacitance diode being adapted to vary the capacity in said resonant circuit and hence the oscillator frequency depending upon the value of a potential applied to said diode, means for applying a variable control voltage to said diode, means for applying the signal output of the oscillator to said diode at a level such that rectification of said signal by said diode occurs and produces a D.C. potential equivalent sufficient to bias said diode to a level where said diode capacity variation with voltage variation is substantially a linear function throughout a substantial portion of the range of voltage variation of said control voltage, means for tuning said oscillator to a selected frequency under conditions where said control voltage is zero, said tuning means including a source of reference frequency slightly different from said selected frequency, means for temporarily applying an appropriate potential to said diode to alter the capacity of said diode to shift the frequency of the oscillator an amount equivalent to substantially the difference between said selected frequency and said reference frequency, means for tuning to the reference frequency with the last said potential temporarily applied, subsequent removal of the tempoRary potential shifting the capacity of said diode and the frequency of the tuned oscillator by the amount of said difference.
Claim 9
Dependent Claim 226 words
A musical instrument oscillator adapted to have its frequency varied as essentially a linear function of a control voltage which fluctuates relative to ground potential, said oscillator including a main capacitance tuning element, a voltage-variable-capacitance diode effectively coupled with said main capacitance element, said voltage variable capacitance diode having essentially a linear change of capacity with respect to the value of a control voltage applied thereto when said diode is biased to a certain voltage level and said control voltage fluctuates relative to said bias voltage level, means for applying the signal output of said oscillator to said diode for rectification thereby at a level such that the rectified oscillator signal produces a D.C. equivalent sufficient to bias said diode to said certain voltage level, means for tuning said oscillator to a selected frequency when said control voltage is zero, said tuning means including means providing a reference frequency slightly different from said selected frequency, means for temporarily applying an appropriate potential to said diode to shift the frequency of the oscillator an amount equivalent to substantially the difference between said selected frequency and said reference frequency, means for tuning to the reference frequency with the last said potential temporarily applied, subsequent removal of the temporary potential shifting the capacity of said diode and the frequency of the tuned oscillator by the amount of said difference.
Claim 10
Dependent Claim 226 words
A musical instrument oscillator adapted to have its frequency varied as essentially a linear function of a control voltage which fluctuates relative to ground potential, said oscillator including a main capacitance tuning element, a voltage-variable-capacitance diode effectively coupled with said main capacitance element, said voltage variable capacitance diode having essentially a linear change of capacity with respect to the value of a control voltage applied thereto when said diode is biased to a certain voltage level and said control voltage fluctuates relative to said bias voltage level, means for applying the signal output of said oscillator to said diode for rectification thereby at a level such that the rectified oscillator signal produces a D.C. equivalent sufficient to bias said diode to said certain voltage level, means for tuning said oscillator to a selected frequency when said control voltage is zero, said tuning means including means providing a reference frequency slightly different from said selected frequency, means for temporarily applying an appropriate potential to said diode to shift the frequency of the oscillator an amount equivalent to substantially the difference between said selected frequency and said reference frequency, means for tuning to the reference frequency with the last said potential temporarily applied, subsequent removal of the temporary potential shifting the capacity of said diode and the frequency of the tuned oscillator by the amount of said difference.

References Cited (Backward Citations)

US25256A Cited
US2719232A Cited
US2936428A Cited
US3499094A Cited
US3601518A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-10-24 1976-04-24 1976-10-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-10-24 1980-04-24 1980-10-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-10-24 1984-04-24 1984-10-24 $7700.00 Window Closed / Lapsed

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