US3859604A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Isolated amplifier
Assignee: Individual
•
Filing: 1972-07-26
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Granted: 1975-01-07
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Expires: 1992-07-26
Abstract
Abstract An audio amplifier in which the input section has means for modulating a radio frequency carrier so that isolation provided by radio frequency coupling allows the output section to obtain power from a power line without a power transformer.
Inventors
- 👤 John Charles Rankin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:05
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/38; H03F3/387; H03C; H03C1/00; H03C1/36
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
107 words
A transistor audio frequency amplifier with two power supplies in which the audio frequency signal to be amplified is used to modulate a radio frequency oscillator the signal being transferred from the first part of the amplifier to the second part of the amplifier by a radio frequency transformer where said audio frequency signal is recovered by demodulation and amplified with said radio frequency transformer providing isolation between the first part of the amplifier which receives power from a line operated transformer type supply and the second part of the amplifier which obtains direct current power for the output transistors from a line operated transformerless power supply.
Claim 2
Dependent Claim
107 words
A transistor audio frequency amplifier with two power supplies in which the audio frequency signal to be amplified is used to modulate a radio frequency oscillator the signal being transferred from the first part of the amplifier to the second part of the amplifier by a radio frequency transformer where said audio frequency signal is recovered by demodulation and amplified with said radio frequency transformer providing isolation between the first part of the amplifier which receives power from a line operated transformer type supply and the second part of the amplifier which obtains direct current power for the output transistors from a line operated transformerless power supply.
Claim 3
Dependent Claim
109 words
A transistor audio frequency amplifier with two power supplies in which the audio frequency signal to be amplified is used to modUlate a radio frequency oscillator the signal being transferred from the first part of the amplifier to the second part of the amplifier by two radio frequency coupling capacitors where said audio frequency signal is recovered by demodulation and amplified with said two radio frequency coupling capacitors providing isolation between the first part of the amplifier which receives power from a line operated transformer type supply and the second part of the amplifier which obtains direct current power for the output transistors from a line operated transformerless supply.
Claim 4
Dependent Claim
109 words
A transistor audio frequency amplifier with two power supplies in which the audio frequency signal to be amplified is used to modUlate a radio frequency oscillator the signal being transferred from the first part of the amplifier to the second part of the amplifier by two radio frequency coupling capacitors where said audio frequency signal is recovered by demodulation and amplified with said two radio frequency coupling capacitors providing isolation between the first part of the amplifier which receives power from a line operated transformer type supply and the second part of the amplifier which obtains direct current power for the output transistors from a line operated transformerless supply.
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 |