US3786303A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cathode ray tube dual mode horizontal deflection control amplifier
Assignee: Honeywell Inc
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Filing: 1971-04-12
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Granted: 1974-01-15
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Expires: 1991-04-12
Abstract
Abstract A dual mode cathode ray tube horizontal deflection amplifier normally operable in a linear mode for horizontal forward scanning and/or symbol writing during the vertical re-trace period and controllably switchable to a non-linear resonant flyback mode for horizontal re-trace. The amplifier comprises a differential input stage cascaded with a push-pull output stage which couples to both the horizontal defection coil of the cathode ray tube and a parallel connected capacitor, forming a resonant circuit. The differential input stage compares the input deflection signal with a feedback signal proportional to the beam deflection to assure linear control. Switch-over to the resonant flyback mode is accomplished by actuating the push-pull stage so as to present a high impedance to the resonant circuit whereupon a half-cycle of oscillation commences to produce the horizontal retrace.
Inventors
- 👤 H Hilburn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:34
CPC Classifications
H; H03; H03K; H03K6/00; H03K6/02; H03K4/00; H03K4/06; H03K4/08; H03K4/48; H03K4/60; H03K4/69; H03K4/693
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
269 words
An electron beam deflection control system including a deflection coil, a capacitor coupled to the deflection coil, and a dual mode amplifier controllably operable in either a linear mode for scanning or stroking the beam or in a resonant nonlinear beam retrace mode, wherein the dual mode amplifier comprises an input stage for receiving an input signal indicative of the desired deflection of the beam, an output stage having first and second push-pull operated sections forming respective halves of the output stage and coupled to receive the output signal of the input stage for controlling current flow through the coil in one direction or the other in accordance with the relative conductivity of the respective sections, each section having an output lead through which the controlled current is supplied to a common output terminal coupled to the coil, unidirectional current conductive means included in the lead between the common output terminal and the first section and poled so that for one polarity of the input signal current is supplied to the coil from said first section via the unidirectional current conductive means for deflecting the beam, and switching means coupled to the second section for abruptly terminating conductive operation thereof occurring in response to the opposite polarity of the input signal whereby as a consequence of the instantaneously non-conductive state of both the first and second sections an interval of resonant oscillation commences between the coil and capacitor for effecting a resonant retrace of the beam, and during which interval the unidirectional current conductive means operates to preclude current flow from the coil and capacitor into said first section.
Claim 2
Dependent Claim
269 words
An electron beam deflection control system including a deflection coil, a capacitor coupled to the deflection coil, and a dual mode amplifier controllably operable in either a linear mode for scanning or stroking the beam or in a resonant nonlinear beam retrace mode, wherein the dual mode amplifier comprises an input stage for receiving an input signal indicative of the desired deflection of the beam, an output stage having first and second push-pull operated sections forming respective halves of the output stage and coupled to receive the output signal of the input stage for controlling current flow through the coil in one direction or the other in accordance with the relative conductivity of the respective sections, each section having an output lead through which the controlled current is supplied to a common output terminal coupled to the coil, unidirectional current conductive means included in the lead between the common output terminal and the first section and poled so that for one polarity of the input signal current is supplied to the coil from said first section via the unidirectional current conductive means for deflecting the beam, and switching means coupled to the second section for abruptly terminating conductive operation thereof occurring in response to the opposite polarity of the input signal whereby as a consequence of the instantaneously non-conductive state of both the first and second sections an interval of resonant oscillation commences between the coil and capacitor for effecting a resonant retrace of the beam, and during which interval the unidirectional current conductive means operates to preclude current flow from the coil and capacitor into said first section.
Claim 3
Dependent Claim
106 words
The system of claim 1 wherein the first and second sections of the push-pull stage each include a plurality of cascaded transistors connEcted such that the last transistor of the first section has its emitter coupled to a potential source of predetermined polarity and its collector connected to the lead including the unidirectional current conductive means which is poled to conduct current supplied from said potential source of predetermined polarity, and the last transistor of the second section has its emitter coupled to a potential source of polarity opposite to said predetermined polarity and its collector connected to the lead coupled to said common output terminal.
Claim 4
Dependent Claim
89 words
The system of claim 2 wherein the switching means for abruptly terminating conductive operation of the second section includes a switching transistor which has its emitter connected to the potential source of opposite polarity and its collector connected to the base of the last transistor of the second section whereby upon the switching transistor being driven into saturation by a switching signal applied thereto the potential source of opposite polarity is applied through said switching transistor to drive the last transistor of the second section into a non-conductive state.
Claim 5
Dependent Claim
66 words
The system of claim 2 wherein the last transistor of the first section is complementary to the last transistor of the second section and in each of the first and second sections the penultimate transistor of the cascaded transistors is connected in parallel with the last transistor and the transistor immediately preceding the penultimate transistor couples to the base of both the penultimate and last transistors.
Claim 6
Dependent Claim
50 words
The system of claim 4 wherein in the second section the transistor immediately preceding the penultimate transistor is connected as an emitter follower which has its base coupled to receive the output signal of the input stage and its emitter coupled to the base of the penultimate and last transistors.
Claim 7
Dependent Claim
33 words
The system of claim 5 including means for applying to the input stage a signal representative of the beam deflection to be compared with the input signal indicative of the desired beam deflection.
Claim 8
Dependent Claim
136 words
The system of claim 6 wherein the switching means for abruptly terminating conductive operation of the second section includes a pair of switching transistors each of which has its emitter connected to the potential source of opposite polarity, the collector of one of the pair of switching transistors connected to the bases of the penultimate and last transistors of the second section and the collector of the other of the pair of switching transistors connected to the base of the emitter follower connected transistor of the second section whereby upon said pair of switching transistors being driven into saturation by a switching signal applied thereto the potential source of opposite polarity is applied through said pair of switching transistors to drive the emitter follower, penultimate, and last transistors of the second section into a non-conductive state.
References Cited (Backward Citations)
US3602768A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-14 | 1977-07-16 | 1978-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-14 | 1981-07-16 | 1982-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-14 | 1985-07-16 | 1986-01-15 | $7700.00 | Window Closed / Lapsed |