US3851269A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hum reduction in transistor amplifiers
Assignee: KHL Research and Development Corp
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Filing: 1972-03-01
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Granted: 1974-11-26
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Expires: 1992-03-01
Abstract
Abstract The low signal hum level in the output of a transistor amplifier is substantially reduced by removing the undesirable ripple voltage normally superimposed on the power supply voltage. A portion of the power supply ripple voltage is capacitively coupled to the emitter electrode of the input transistor stage which provides an out of phase ripple voltage to substantially cancel the ripple voltage appearing at the output terminals.
Inventors
- 👤 J Szorc
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:39
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/30; H03F3/3069; H03F3/3071; H03F1/00; H03F1/30; H03F1/302
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
239 words
A signal translating system comprising: a. a transistor input stage of amplification including a transistor having emitter, base and collector electrodes, said base electrode being adapted to be coupled to a signal voltage source; b. a power supply having first and second terminals and providing between said terminals a DC voltage having a ripple voltage superimposed thereon; c. a transistor output stage including at least a pair of transistors having emitter, base and collector electrodes, said emitter and collector electrodes of said output stage being serially connected between the first and second terminals of said power supply, said base electrodes of said output stage being coupled to said input stage collector electrode, said serially connected output stage electrodes being coupled to said input stage emitter electrode and to an output terminal; d. DC bias means coupled from said power supply terminals to the base electrodes of said input and said output stages for biasing said stages to their respective operating points; e. voltage divider means having a tap thereon, connected between the first and second terminals of said power supply for obtaining a portion of said ripple voltage, and f. a capacitor connected between said voltage divider tap and the emitter electrode of said input transistor to produce a ripple compensating voltage in said output stage to substantially cancel the ripple appearing at said output terminal, said tap being not coupled to any other electrode of said input transistor.
Claim 2
Dependent Claim
239 words
A signal translating system comprising: a. a transistor input stage of amplification including a transistor having emitter, base and collector electrodes, said base electrode being adapted to be coupled to a signal voltage source; b. a power supply having first and second terminals and providing between said terminals a DC voltage having a ripple voltage superimposed thereon; c. a transistor output stage including at least a pair of transistors having emitter, base and collector electrodes, said emitter and collector electrodes of said output stage being serially connected between the first and second terminals of said power supply, said base electrodes of said output stage being coupled to said input stage collector electrode, said serially connected output stage electrodes being coupled to said input stage emitter electrode and to an output terminal; d. DC bias means coupled from said power supply terminals to the base electrodes of said input and said output stages for biasing said stages to their respective operating points; e. voltage divider means having a tap thereon, connected between the first and second terminals of said power supply for obtaining a portion of said ripple voltage, and f. a capacitor connected between said voltage divider tap and the emitter electrode of said input transistor to produce a ripple compensating voltage in said output stage to substantially cancel the ripple appearing at said output terminal, said tap being not coupled to any other electrode of said input transistor.
Claim 3
Dependent Claim
31 words
A signal translating system according to claim 1 wherein said voltage divider means comprises a first and second resistor connected in series with their common connection being said voltage divider tap.
Claim 4
Dependent Claim
164 words
In a transistorized amplifier of the type having an output terminal, an input amplifying transistor stage having substantial gain and including an input transistor having emitter, base and collector electrodes, and an output stage including at least one transistor, a DC voltage source having a ripple component, said voltage source having first and second terminals, said input and output transistor stages being biased to their operating points by means coupled to said DC voltage source, the improvement comprising circuit means interconnecting the electrodes of said input transistor to provide substantial gain at an output electrode thereof of an input signal applIed to an input electrode thereof, and voltage divider and AC coupling means connected between said first and second terminals of said voltage source and to only the remaining one of said input transistor electrodes of said amplifying stage for providing to said one only electrode a portion of only said ripple component for substantially cancelling the ripple voltage appearing at said output terminal.
Claim 5
Dependent Claim
164 words
In a transistorized amplifier of the type having an output terminal, an input amplifying transistor stage having substantial gain and including an input transistor having emitter, base and collector electrodes, and an output stage including at least one transistor, a DC voltage source having a ripple component, said voltage source having first and second terminals, said input and output transistor stages being biased to their operating points by means coupled to said DC voltage source, the improvement comprising circuit means interconnecting the electrodes of said input transistor to provide substantial gain at an output electrode thereof of an input signal applIed to an input electrode thereof, and voltage divider and AC coupling means connected between said first and second terminals of said voltage source and to only the remaining one of said input transistor electrodes of said amplifying stage for providing to said one only electrode a portion of only said ripple component for substantially cancelling the ripple voltage appearing at said output terminal.
Claim 6
Dependent Claim
171 words
In a transistorized amplifier of the type having an output terminal, an input amplifying transistor stage having substantial gain and including an input transistor having emitter, base and collector electrodes, and an output stage including at least one transistor, a DC voltage source having a ripple component, said voltage source having first and second terminals, said input and output transistor stages being biased to their operating points by means coupled to said DC voltage source, the improvement comprising voltage divider and AC coupling means connected between said first and second terminals of said voltage source and to only one of said input transistor electrodes of said amplifying stage for providing to said one only electrode a portion of only said ripple component for substantially cancelling the ripple voltage appearing at said output terminal, wherein said voltage divider and AC coupling means comprises resistor means connected between said first and second terminals of said voltage source, and capacitor means connecting an intermediate point of said resistor means to said one only electrode.
Claim 7
Dependent Claim
171 words
In a transistorized amplifier of the type having an output terminal, an input amplifying transistor stage having substantial gain and including an input transistor having emitter, base and collector electrodes, and an output stage including at least one transistor, a DC voltage source having a ripple component, said voltage source having first and second terminals, said input and output transistor stages being biased to their operating points by means coupled to said DC voltage source, the improvement comprising voltage divider and AC coupling means connected between said first and second terminals of said voltage source and to only one of said input transistor electrodes of said amplifying stage for providing to said one only electrode a portion of only said ripple component for substantially cancelling the ripple voltage appearing at said output terminal, wherein said voltage divider and AC coupling means comprises resistor means connected between said first and second terminals of said voltage source, and capacitor means connecting an intermediate point of said resistor means to said one only electrode.
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) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |