US3742261A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solid state vacuum tube replacement
Assignee: Teledyne Inc
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Filing: 1971-10-06
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Granted: 1973-06-26
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Expires: 1991-10-06
Abstract
Abstract A solid state assembly and base which can be plugged as a replacement directly into a vacuum tube socket in a vacuum tube circuit and provide the same characteristics as the vacuum tube which it replaces.
Inventors
- 👤 E Schneider
- 👤 B Burman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:46
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/32; H03F1/3241; H03F1/3264; H03F1/327; H03F3/00; H03F3/04; H03F3/16; H03F3/165; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/687; H10; H10W; H10W90/00; H10W90/701; H10W90/751; H10W90/754
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
127 words
A vacuum tube replacement comprising a base having a plurality of pins adapted to fit in a vacuum tube socket as a replacement for a vacuum tube, a First high gain, low voltage field effect transistor having source, drain and gate electrodes, a second high voltage, moderate gain field effect transistor having source, drain and gate electrodes, said transistors connected with the source of the first to the cathode pin of said base and to the gate terminal of said second transistor, the gate terminal of said first transistor connected to the grid pin of said base, the drain terminal of said first transistor connected to the source terminal of the second and the drain terminal of the second connected to the plate pin of said base.
Claim 2
Dependent Claim
127 words
A vacuum tube replacement comprising a base having a plurality of pins adapted to fit in a vacuum tube socket as a replacement for a vacuum tube, a First high gain, low voltage field effect transistor having source, drain and gate electrodes, a second high voltage, moderate gain field effect transistor having source, drain and gate electrodes, said transistors connected with the source of the first to the cathode pin of said base and to the gate terminal of said second transistor, the gate terminal of said first transistor connected to the grid pin of said base, the drain terminal of said first transistor connected to the source terminal of the second and the drain terminal of the second connected to the plate pin of said base.
Claim 3
Dependent Claim
143 words
A vacuum tube replacement as in claim 1 wherein said first transistor has a saturation current at 15 volts of between 15 and 24 milliamps; maximum pinchoff voltage of less than 7 volts with a source to drain current of 10 microamps at 10 volts applied between the drain and source; and breakdown voltages greater than 25 volts with the gate source and gate drain shorted to one another, and said second transistor has a saturation current at 20 volts between 20 and 50 milliamps; a pinchoff voltage less than 20 volts with source to drain current of 100 microamps and 5 volts applied between the drain and source; breakdown voltage, drain to gate at 10 microamps of greater than 275 volts with the source open; and a breakdown voltage, source to gate with drain open at 10 milliamps greater than 50 volts.
Claim 4
Dependent Claim
144 words
A vacuum tube replacement as in claim 1 wherein said first transistor has a saturation current at 15 volts of between 1 and 60 milliamps; maximum pinchoff voltage of less than 20 volts with a source to drain current of 10 microamps at 10 volts applied between the drain and source; and breakdown voltages greater than 25 volts with the gate source and gate drain shorted to one another, and said second transistor has a saturation current at 20 volts between 10 and 150 milliamps; a pinchoff voltage less than 20 volts with a source to drain current of 10 microamps at 5 volts applied between the drain and source; breakdown voltage, drain to gate, at 10 microamps of greater than 200 volts with the source open; and breakdown voltage, source to gate with drain open at 10 microamps of greater than 50 volts.
Claim 5
Dependent Claim
27 words
A vacuum tube replacement as in claim 1 including a fuse connected between the drain terminal of the second transistor and the plate pin of said base.
Claim 6
Dependent Claim
24 words
A vacuum tube replacement as in claim 1 wherein said first and second transistors are mounted on a ceramic wafer carried on said base.
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) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |