US3743882A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit arrangement for generating an amplitude-modulated sawtooth voltage
Assignee: US Philips Corp
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Filing: 1971-10-06
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Granted: 1973-07-03
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Expires: 1991-10-06
Abstract
Abstract A circuit arrangement for generating an amplitude-modulated sawtooth voltage of line frequency modulated in amplitude by a voltage of field frequency, particularly for the corner convergence in a colour television display apparatus. A capacitor is charged by a voltage pulse of line frequency and is discharged by a current which is proportional to the instantaneous value of a sawtooth voltage of field frequency.
Inventors
- 👤 K Kroner
- 👤 H Feindt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:34
CPC Classifications
H; H04; H04N; H04N3/00; H04N3/10; H04N3/16; H04N3/22; H04N3/23; H04N3/233
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
135 words
A circuit comprising a first diode having a first electrode adapted to receive a television line frequency pulse, and a second electrode; a first capacitor having a first end coupled to said diode second electrode, and a second end; a first transistor having an emitter electrode coupled to ground, a base electrode coupled to said capacitor second end, and a collector electrode; a first resistor having a first end coupled to said base, and a second end adapted to receive a television field frequency sawtooth waveform voltage; a second resistor having a first end coupled to said collector, and a second end coupled to said capacitor first end; and output means coupled to said capacitor first end for providing an output signal of a line frequency sawtooth waveform having a field frequency varying amplitude envelope.
Claim 2
Dependent Claim
135 words
A circuit comprising a first diode having a first electrode adapted to receive a television line frequency pulse, and a second electrode; a first capacitor having a first end coupled to said diode second electrode, and a second end; a first transistor having an emitter electrode coupled to ground, a base electrode coupled to said capacitor second end, and a collector electrode; a first resistor having a first end coupled to said base, and a second end adapted to receive a television field frequency sawtooth waveform voltage; a second resistor having a first end coupled to said collector, and a second end coupled to said capacitor first end; and output means coupled to said capacitor first end for providing an output signal of a line frequency sawtooth waveform having a field frequency varying amplitude envelope.
Claim 3
Dependent Claim
167 words
A circuit as claimed in claim 1 wherein said diode first and second ends comprise an anode and cathode respectively, said pulses comprise positive pulses, said transistor comprises an npn type transistor, and further comprising a second diode having a cathode adapted to receive negative television line frequency pulses, and an anode; a second capacitor having a first end coupled to said second diode anode, and a second end; a pnp type second transistor having an emitter electrode coupled to ground, a base electrode coupled to said second capacitor second end, and a collector electrode; a third resistor having a first end coupled to said second transistor base, and a second end adapted to receive said field frequency sawtooth waveform voltage; a fourth resistor having a first end coupled to said second transistor collector, and a second end coupled to said second capacitor first end; and said output means being coupled to said second capacitor first end; whereby said output signal has both positive and negative portions.
Claim 4
Dependent Claim
32 words
A circuit as claimed in claim 2 further comprising a fifth resistor having a first end adapted to receive said field frequency voltage, and a second end coupled to said output means.
Claim 5
Dependent Claim
30 words
A circuit as claimed in claim 2 wherein said second ends of said first and third resistors are adapted to further receive a field frequency modulated line frequency parabola voltage.
Claim 6
Dependent Claim
15 words
A circuit as claimed in claim 4 further comprising an integrator coupled to said output.
Claim 7
Dependent Claim
23 words
A circuit as claimed in claim 2 further comprising a third capacitor coupled between said first diode cathode and said second diode anode.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-02 | 1977-01-01 | 1977-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-02 | 1981-01-01 | 1981-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-02 | 1985-01-01 | 1985-07-03 | $7700.00 | Window Closed / Lapsed |