US3582800A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-noise video amplifier
Assignee: Robert Bosch Fernsehanlagen GmbH
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Filing: 1969-09-12
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Granted: 1971-06-01
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Expires: 1989-09-12
Abstract
Abstract A video signal amplifier having a low noise-to-signal ratio. The amplifier has a cascade stage with a high impedance input stage for amplifying the signal applied to it. A load resistor in the form of a voltage divider is connected to the output of the amplifier, and the output signal appears across this voltage divider. The voltage divider has a low ohmic branch which may be tapped off. A negative feedback resistor is connected across the low ohmic branch of the output voltage divider, and to the input stage of the amplifier. Through this arrangement the operating point of the input stage is exclusively established by the DC potential of the point at which the negative feedback resistor is connected to the output voltage divider or load resistor. The input signal to the amplifier may be capacitively coupled to the input stage. An impedance converter may also be connected to the amplifier output and to the cascade stage. An input resistor may be provided for applying the signal to be amplified to the input stage. The negative feedback resistor is of high impedance, of the order of 1 megohm. The amplifier is applicable as a video preamplifier for amplifying signals from television pickup tubes with high signal-to-noise ratio.
Inventors
- 👤 Klaus Lehmann
- 👤 Emil Siegel
- 👤 Manfred Kreuzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:41
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/148; H03; H03F; H03F1/00; H03F1/08; H03F1/22; H03F1/24; H03F1/26; H03F1/32; H03F1/34; H03F1/36; H03F1/56; H03F1/565; H03F3/00; H03F3/04; H03F3/16; H03F3/189; H03F3/19; H03F3/193; H03F3/1935; H03F3/42; H03F3/44
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
111 words
A signal amplifier comprising, in combination, a cascode arrangement of two amplifying elements, one of said amplifying elements being connected as a grounded emitter circuit and the other of said amplifying elements being connected as a grounded base circuit; an emitter follower input stage with output connected to the input of said cascade arrangement; load resistor means of said cascade arrangement across which the output signal of said amplifier appears; and impedance means substantially high in impedance compared to said input stage and connected between the input of said emitter follower stage and said load resistor means, the input of said emitter follower input stage being the input to said amplifier.
Claim 2
Dependent Claim
111 words
A signal amplifier comprising, in combination, a cascode arrangement of two amplifying elements, one of said amplifying elements being connected as a grounded emitter circuit and the other of said amplifying elements being connected as a grounded base circuit; an emitter follower input stage with output connected to the input of said cascade arrangement; load resistor means of said cascade arrangement across which the output signal of said amplifier appears; and impedance means substantially high in impedance compared to said input stage and connected between the input of said emitter follower stage and said load resistor means, the input of said emitter follower input stage being the input to said amplifier.
Claim 3
Dependent Claim
23 words
The signal amplifier as defined in claim 1, including coupling resistor means connected between the input and the output of said signal amplifier.
Claim 4
Dependent Claim
17 words
The signal amplifier as defined in claim 1, wherein said impedance means is at least 1 megohm.
Claim 5
Dependent Claim
45 words
The signal amplifier as defined in claim 1, including input resistor means connected to said emitter follower input stage of said amplifier, the input signal to be amplified by said amplifier being applied to the junction of said input stage and said input resistor means.
Claim 6
Dependent Claim
34 words
The signal amplifier as defined in claim 1, including capacitor means connected to said emitter follower input stage, the input signal to said amplifier being applied to said input stage through said capacitor means.
Claim 7
Dependent Claim
37 words
The signal amplifier as defined in claim 1, wherein said load resistor means comprises a voltage divider having a branch connected across said impedance means, said branch having substantially low ohmic value compared to said impedance means.
Claim 8
Dependent Claim
118 words
A signal amplifier comprising, in combination, a cascade arrangement of two amplifying junction transistors, one of said transistors being connected as a grounded emitter circuit and the other of said transistors being connected as a grounded base circuit; a source follower input stage having a field effect transistor, said input stage having an output connected to the input of said cascade arrangement; load resistor means of said cascade arrangement across which the output signal of said amplifier appears; and impedance means substantially high in impedance compared to said input stage and connected between the input of said source follower and said load resistor means, the input of said source follower input stage being the input to said amplifier.
Claim 9
Dependent Claim
118 words
A signal amplifier comprising, in combination, a cascade arrangement of two amplifying junction transistors, one of said transistors being connected as a grounded emitter circuit and the other of said transistors being connected as a grounded base circuit; a source follower input stage having a field effect transistor, said input stage having an output connected to the input of said cascade arrangement; load resistor means of said cascade arrangement across which the output signal of said amplifier appears; and impedance means substantially high in impedance compared to said input stage and connected between the input of said source follower and said load resistor means, the input of said source follower input stage being the input to said amplifier.
Claim 10
Dependent Claim
118 words
A transistor signal amplifier comprising, in combination, a cascade arrangement of two semiconductor elements, one of said elements being connected as a grounded emitter circuit and the other of said elements being connected as a grounded base circuit; a source follower input stage having a field effect transistor, said input stage having an output connected to the input of said cascade arrangement; load resistor means of said cascade arrangement across which the output signal of said amplifier appears; and impedance means substantially high in impedance compared to said input stage and connected between the input of said source follower and said load resistor means, the input of said source follower input stage being the input to said amplifier.
Claim 11
Dependent Claim
118 words
A transistor signal amplifier comprising, in combination, a cascade arrangement of two semiconductor elements, one of said elements being connected as a grounded emitter circuit and the other of said elements being connected as a grounded base circuit; a source follower input stage having a field effect transistor, said input stage having an output connected to the input of said cascade arrangement; load resistor means of said cascade arrangement across which the output signal of said amplifier appears; and impedance means substantially high in impedance compared to said input stage and connected between the input of said source follower and said load resistor means, the input of said source follower input stage being the input to said amplifier.
References Cited (Backward Citations)
US3001144A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-31 | 1974-11-30 | 1975-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-31 | 1978-11-30 | 1979-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-31 | 1982-11-30 | 1983-06-01 | $7700.00 | Window Closed / Lapsed |