Patent US3859607A successfully refreshed from Google Patents.
US3859607A
Expired / Lapsed
US
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Sweep generator with crystal controlled center frequency
Assignee: TELONIC IND Inc
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Filing: 1973-06-04
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Granted: 1975-01-07
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Expires: 1993-06-04
Abstract
Abstract An electronic sweep generator, particularly adapted to the calibration and measurement of television tuners, in which the sweep center frequency is automatically controlled and frequency markers are generated using a crystal oscillator, a frequency synthesizer and a harmonic generator; a harmonic selection circuit being used to blank all but the desired harmonic.
Inventors
- 👤 Bruce H Brazelton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:12
CPC Classifications
H; H03; H03B; H03B23/00; H03C; H03C3/00; H03C3/02; H03C3/09; H03C3/0908
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
188 words
A sweep generator, comprising: variable oscillator means for supplying an output signal which continously varies in frequency through a frequency range; a crystal oscillator for providing a stable, fixed frequency output signal; a frequency synthesizer, comprising: a controlled oscillator for producing an adjustable frequency output in response to an input signal; means for reducing said adjustable frequency output by a predetermined factor to produce a scaled output; and means for comparing said scaled output with said fixed frequency output to produce said input signal; means for operatively coupling said frequency synthesizer to said variable oscillator means to produce marker signals referenced to said crystal oscillator, said means for operatively coupling comprising: a mixer for heterodyning said adjustable frequency output and the output of said variable oscillator means to produce a heterodyne signal; a second crystal oscillator for providing a second stable fixed frequency output signal; a second mixer for heterodyning said heterodyne signal with said second fixed frequency output signal for producing a second heterodyne signal having a frequency null point; and a bandpass filter for filtering said second heterodyne signal to produce a pair of marker signals.
Claim 2
Dependent Claim
188 words
A sweep generator, comprising: variable oscillator means for supplying an output signal which continously varies in frequency through a frequency range; a crystal oscillator for providing a stable, fixed frequency output signal; a frequency synthesizer, comprising: a controlled oscillator for producing an adjustable frequency output in response to an input signal; means for reducing said adjustable frequency output by a predetermined factor to produce a scaled output; and means for comparing said scaled output with said fixed frequency output to produce said input signal; means for operatively coupling said frequency synthesizer to said variable oscillator means to produce marker signals referenced to said crystal oscillator, said means for operatively coupling comprising: a mixer for heterodyning said adjustable frequency output and the output of said variable oscillator means to produce a heterodyne signal; a second crystal oscillator for providing a second stable fixed frequency output signal; a second mixer for heterodyning said heterodyne signal with said second fixed frequency output signal for producing a second heterodyne signal having a frequency null point; and a bandpass filter for filtering said second heterodyne signal to produce a pair of marker signals.
Claim 3
Dependent Claim
30 words
A sweep generator as defined in claim 1 wherein said bandpass filter is tuned to produce a pair of marker signals equally spaced above and below said frequency null point.
Claim 4
Dependent Claim
172 words
A sweep generator, comprising: variable oscillator means for supplying an output signal which continuously varies in frequency through a frequency range; a crystal oscillator for providing a stable, fixed frequency output signal; a frequency synthesizer, comprising: a controlled oscillator for producing an adjustable frequency output in response to an input signal; means for reducing said adjustable frequency output by a predetermined factor to produce a scalEd output; and means for comparing said scaled output with said fixed frequency output to produce said input signal; means for operatively coupling said frequency synthesizer to said variable oscillator means to produce marker signals referenced to said crystal oscillator, said means for operatively coupling comprising: a mixer for heterodyning said adjustable frequency output and the output of said variable oscillator means to produce a heterodyne signal; a filter for filtering said heterodyne signal to produce a marker signal; and means for controlling the center frequency of said continuously varying frequency signal of said variable oscillator in response to said marker signals without varying said frequency range.
Claim 5
Dependent Claim
172 words
A sweep generator, comprising: variable oscillator means for supplying an output signal which continuously varies in frequency through a frequency range; a crystal oscillator for providing a stable, fixed frequency output signal; a frequency synthesizer, comprising: a controlled oscillator for producing an adjustable frequency output in response to an input signal; means for reducing said adjustable frequency output by a predetermined factor to produce a scalEd output; and means for comparing said scaled output with said fixed frequency output to produce said input signal; means for operatively coupling said frequency synthesizer to said variable oscillator means to produce marker signals referenced to said crystal oscillator, said means for operatively coupling comprising: a mixer for heterodyning said adjustable frequency output and the output of said variable oscillator means to produce a heterodyne signal; a filter for filtering said heterodyne signal to produce a marker signal; and means for controlling the center frequency of said continuously varying frequency signal of said variable oscillator in response to said marker signals without varying said frequency range.
Claim 6
Dependent Claim
23 words
A sweep generator as defined in claim 3 wherein said means for reducing said adjustable frequency comprises a variable divide-by-N digital divider circuit.
Claim 7
Dependent Claim
37 words
A sweep generator as defined in claim 4 wherein said means for reducing said adjustable frequency additionally comprises means for adjusting the reduction factor of said divide-by-N digital divider circuit in response to a digital signal input.
Claim 8
Dependent Claim
116 words
A sweep generator for cyclically producing a variable frequency output signal, said sweep generator including a marker system comprising: an oxcillator for producing a first frequency signal; a harmonic generator responsive to said first frequency signal for producing a plurality of harmonic signals from said first frequency signal; means for selecting one of said plurality of harmonic signals; and means for producing a marker signal only in response to said selected one of said plurality of harmonic signals, comprising: means for heterodyning the output of said means for selecting one of said plurality of harmonic signals with said variable frequency output signal; and a filter coupled to said means for heterodyning for producing said marker signal.
Claim 9
Dependent Claim
116 words
A sweep generator for cyclically producing a variable frequency output signal, said sweep generator including a marker system comprising: an oxcillator for producing a first frequency signal; a harmonic generator responsive to said first frequency signal for producing a plurality of harmonic signals from said first frequency signal; means for selecting one of said plurality of harmonic signals; and means for producing a marker signal only in response to said selected one of said plurality of harmonic signals, comprising: means for heterodyning the output of said means for selecting one of said plurality of harmonic signals with said variable frequency output signal; and a filter coupled to said means for heterodyning for producing said marker signal.
Claim 10
Dependent Claim
28 words
A sweep generator as defined in claim 6 wherein said filter comprises a bandpass filter coupled to said means for heterodyning for producing a pair of marker signals.
Claim 11
Dependent Claim
73 words
A sweep generator as defined in claim 6, said sweep generator producing a ramp signal, wherein said means for selecting comprises: means for generating an analog signal having an amplitude proportional to the frequency of said first frequency signal; means for comparing the amplitude of said analog signal with the amplitude of said ramp signal to produce a gating signal; and means for enabling said harmonic generator in response to said gating signal.
Claim 12
Dependent Claim
22 words
A sweep generator as defined in claim 6 wherein said oscillator is crystal controlled, so that said marker signal is crystal referenced.
Claim 13
Dependent Claim
24 words
A sweep generator as defined in claim 6 additionally comprising means for centering said variable frequency output signal in response to said marker signal.
Claim 14
Dependent Claim
57 words
A sweep generator as defined in claim 6 wherein said oscillator comprises: a frequency signal source for producing a first oscillation signal; and a frequency synthesizer responsive to said first oscillation signal for producing a second oscillation signal which is a predetermined multiple of said first oscillation signal, said second oscillation signal being said first frequency signal.
Claim 15
Dependent Claim
162 words
A sweep generator, comprising: variable oscillator means for supplying an output signal which continuously varies in frequency through a frequency range centered at a center frequency; a crystal oscillator for providing a stable, fixed frequency output signal; a frequency synthesizer, comprising: a voltage controlled oscillator for producing an adjustable frequency output in response to an input voltage signal; means for reducing said adjustable frequency output by a predetermined factor to produce a scaled output; and means for comparing said scaled output with said fixed frequency output to produce said input voltage signal; means responsive to the oUtput of said frequency synthesizer for automatically controlling said center frequency of said variable oscillator means without changing said frequency range, comprising: a mixer for heterodyning said adjustable frequency output with said variable oscillator output signal to produce a heterodyne signal; and a filter coupled to receive said heterodyne signal for producing an output signal for automatically controlling said center frequency of said variable oscillator means.
Claim 16
Dependent Claim
162 words
A sweep generator, comprising: variable oscillator means for supplying an output signal which continuously varies in frequency through a frequency range centered at a center frequency; a crystal oscillator for providing a stable, fixed frequency output signal; a frequency synthesizer, comprising: a voltage controlled oscillator for producing an adjustable frequency output in response to an input voltage signal; means for reducing said adjustable frequency output by a predetermined factor to produce a scaled output; and means for comparing said scaled output with said fixed frequency output to produce said input voltage signal; means responsive to the oUtput of said frequency synthesizer for automatically controlling said center frequency of said variable oscillator means without changing said frequency range, comprising: a mixer for heterodyning said adjustable frequency output with said variable oscillator output signal to produce a heterodyne signal; and a filter coupled to receive said heterodyne signal for producing an output signal for automatically controlling said center frequency of said variable oscillator means.
Claim 17
Dependent Claim
44 words
A sweep generator as defined in claim 12 additionally comprising: a second crystal oscillator for providing a second stable fixed frequency output signal; and means for mixing said heterodyne signal with said second stable fixed frequency output signal to produce a second heterodyne signal.
Claim 18
Dependent Claim
24 words
A sweep generator as defined in claim 12 wherein said means for reducing said adjustable frequency output comprises a variable divide-by-N digital divider circuit.
Claim 19
Dependent Claim
32 words
A sweep generator as defined in claim 14 wherein said means for reducing said adjustable frequency output additionally comprises means for adjusting the reduction factor of said variable divide-by-N digital dividing circuit.
Claim 20
Dependent Claim
175 words
A marker generator for producing crystal controlled marker pulses in a sweep generator system, said sweep generator system producing a ramp signal and a cyclicly varying frequency signal proportional in frequency to the amplitude of said ramp signal, comprising: a crystal controlled oscillator for producing a first frequency output signal; a frequency synthesizer responsive to said first frequency output signal for producing a second frequency output signal which is a predetermined multiple of said first frequency output signal; means for comparing said first frequency output signal with said second frequency output signal to generate an analog signal indicative of said second frequency; a harmonic generator connected to said second frequency output signal for producing harmonic signals; gate means responsive to said ramp signal and said analog signal for selectively enabling said harmonic generator in response to a predetermined relationship of said ramp signal to said analog signal; means for heterodyning said harmonic signals with said cyclicly varying frequency signal; and means for filtering the output of said means for heterodyning to produce a marker signal.
Claim 21
Dependent Claim
175 words
A marker generator for producing crystal controlled marker pulses in a sweep generator system, said sweep generator system producing a ramp signal and a cyclicly varying frequency signal proportional in frequency to the amplitude of said ramp signal, comprising: a crystal controlled oscillator for producing a first frequency output signal; a frequency synthesizer responsive to said first frequency output signal for producing a second frequency output signal which is a predetermined multiple of said first frequency output signal; means for comparing said first frequency output signal with said second frequency output signal to generate an analog signal indicative of said second frequency; a harmonic generator connected to said second frequency output signal for producing harmonic signals; gate means responsive to said ramp signal and said analog signal for selectively enabling said harmonic generator in response to a predetermined relationship of said ramp signal to said analog signal; means for heterodyning said harmonic signals with said cyclicly varying frequency signal; and means for filtering the output of said means for heterodyning to produce a marker signal.
Claim 22
Dependent Claim
54 words
A marker generator as defined in claim 16 additionally comprising: means for adjusting said means for comparing to produce an analog signal which permits said gate means to enable said harmonic generator only when said cyclicly varying frequency signal has a predetermined frequency relationship with a predetermined harmonic of said second frequency output signal.
Claim 23
Dependent Claim
133 words
A sweep generator having a sweep width and a center frequency fc which automatically varies in accordance with the time of occurrence of a marker pulse, comprising: a crystal controlled frequency synthesizer for producing a first frequency signal; means for heterodyning said first frequency signal with the output of said sweep generator to produce a first heterodyne signal; an oscillator for producing a second frequency signal; means for heterodyning said first heterodyne signal with said second frequency signal to produce a second heterodyne signal; means for producing said marker pulse, said means comprising: a filter responsive to said second heterodyne signal for producing a filtered output; and a pulse generator responsive to said filtered output; and means responsive to said marker pulse for controlling said center frequency fc independent of said sweep width.
Claim 24
Dependent Claim
133 words
A sweep generator having a sweep width and a center frequency fc which automatically varies in accordance with the time of occurrence of a marker pulse, comprising: a crystal controlled frequency synthesizer for producing a first frequency signal; means for heterodyning said first frequency signal with the output of said sweep generator to produce a first heterodyne signal; an oscillator for producing a second frequency signal; means for heterodyning said first heterodyne signal with said second frequency signal to produce a second heterodyne signal; means for producing said marker pulse, said means comprising: a filter responsive to said second heterodyne signal for producing a filtered output; and a pulse generator responsive to said filtered output; and means responsive to said marker pulse for controlling said center frequency fc independent of said sweep width.
Claim 25
Dependent Claim
53 words
A sweep generator as defined in claim 18 wherein said crystal controlled frequency synthesizer comprises: means for generating a fixed frequency signal; means for generating harmonics of said fixed frequency signal; and means for selecting only one oF said harmonics of said fixed frequency signal, said selected signal being said first frequency signal.
Claim 26
Dependent Claim
22 words
A sweep generator as defined in claim 18 wherein said oscillator for producing a second frequency signal is a crystal controlled oscillator.
Claim 27
Dependent Claim
85 words
A digitally controlled oscillator, comprising: a cyclic frequency generator for repetitively producing an output signal which sweeps through frequencies between a predetermined minimum and maximum frequency, said frequency generator additionally producing a ramp signal having an instantaneous amplitude which is proportional to the instantaneous frequency of said output signal; a frequency signal source; means for selectively enabling said frequency source in response to the instantaneous amplitude of said ramp signal; and means for heterodyning the output of said frequency signal source with said output signal.
Claim 28
Dependent Claim
85 words
A digitally controlled oscillator, comprising: a cyclic frequency generator for repetitively producing an output signal which sweeps through frequencies between a predetermined minimum and maximum frequency, said frequency generator additionally producing a ramp signal having an instantaneous amplitude which is proportional to the instantaneous frequency of said output signal; a frequency signal source; means for selectively enabling said frequency source in response to the instantaneous amplitude of said ramp signal; and means for heterodyning the output of said frequency signal source with said output signal.
Claim 29
Dependent Claim
66 words
A digitally controlled oscillator as defined in claim 21 wherein said frequency signal source comprises: an oscillator for producing a first frequency output signal; and a frequency synthesizer responsive to said first frequency output signal for producing a second frequency output signal which is a predetermined multiple of said first frequency output signal, said second frequency output signal being the output of said frequency signal source.
Claim 30
Dependent Claim
30 words
A digitally controlled oscillator as defined in claim 22 wherein said frequency signal source additionally comprises: a harmonic generator connected to said second frequency output signal for producing harmonic signals.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-06 | 1978-07-08 | 1979-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-06 | 1982-07-08 | 1983-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-06 | 1986-07-08 | 1987-01-07 | $7700.00 | Window Closed / Lapsed |