Hybrid feedback amplifier

Claim 2

A hybrid feedback amplifier comprising: an autotransformer having a winding and a center tap dividing said winding into a plurality of portions; an amplifier section; a feedback network; means for connecting a signal carrying network across essentially the series combination of one terminal pair of said amplifier section and one portion of said autotransformer; a terminating resistor connected across essentially the series combination of said one terminal pair and said winding, having such value that the signal on said signal carrying network appears as substantially equal voltages across said one terminal pair and said terminating resistor with a zero net signal voltage across said feedback network; and means for feeding back a part of the output signal of said amplifier section to the input of said amplifier through said feedback network.

Claim 3

A hybrid feedback amplifier as claimed in claim 1 wherein, said one terminal pair of said amplifier section is the input terminal pair, and said autotransformer has first and second end terminals, a first terminal of said input pair being connected to the non-grounded input terminal of said hybrid feedback amplifier and one side of said terminating resistor, the other side of said terminating resistor being connected to the second end terminal of said autotransformer, the first end terminal of said autotransformer being connected to second terminal of said input pair.

Claim 4

A hybrid feedback network as claimed in claim 2 wherein said means for feeding back is connected between one terminal of an output terminal pair of said amplifier section and said second end terminal of said autotransformer.

Claim 5

A hybrid feedback network as claimed in claim 2 wherein said means for feeding back is connected between one terminal of an output terminal pair of said amplifier section and said first terminal of said autotransformer.

Claim 6

A hybrid feedback amplifier as claimed in claim 1 wherein said one terminal pair of said amplifier section is the output terminal pair, and said autotransformer has first and second end terminals, a first terminal of said output pair serving as one output terminal of said hybrid amplifier and being connected to one side of said terminating resistor, the other side of said terminating resistor being connected to the second end terminal of said autotransformer, the first end terminal of said autotransformer being connected to the second of said output terminal pair, an input terminal pair of said amplifier section, and said means for feeding back being connected between one of the input terminal pair of said amplifier section and one of the end terminals of said autotransformer.

Claim 7

A hybrid feedback amplifier as claimed in claim 5 wherein said means for feeding back is connected to the first end terminal of said autotransformer.

Claim 8

A hybrid feedback amplifier as claimed in claim 5 wherein said means for feeding back is connected to the second end terminal of said autotransformer. 8. A hybrid feedback amplifier as claimed in claim 1 wherein said amplifier section has an input terminal pair and an output terminal pair and is operable to invert a signal between said input and output terminal pair, said autotransformer having first and second end terminals connected respectively to one of said input terminal pair and one side of said terminating resistor, the other said input terminal pair being connected to the other side of said terminating resistor, said hybrid feedback amplifier comprising a second autotransformer having first and second end terminals and a center tap, said first end terminal of said second autotransformer being connected to one of the output terminal pair of said amplifier section, and a second terminating resistor connected between the other of said output terminal pair and the second end terminal of said second autotransformer, and wherein said means for feeding back is connected between like end terminals of said first and second autotransformers.

Claim 9

A hybrid feedback amplifier as claimed in claim 8 wherein said first and second autotransformers have their center taps grounded.

Claim 10

A hybrid feedback amplifier as claimed in claim 2 further comprising an output terminal pair of said amplifier section, a second terminating resistor having one end connected to one of said output terminal pair and the other end connected to said second end terminal, and an additional tap on said autotransformer intermediate said center tap and said end terminal and being connected to the other of said output terminal pair, and wherein said amplifier section comprises amplifier stages for inverting the signal polarity between said input and output terminal pairs.

Claim 11

A hybrid feedback amplifier as claimed in claim 1 wherein said amplifier section comprises an input terminal pair and output terminal pair and amplifier means for amplifying a signal without causing phase reversal between said input and output terminal pairs, said autotransformer having first and second end terminals and an additional tap between said center tap and said first end terminal, said terminating resistor being connected between one of said output terminal pair and said first end terminal, the other of said output terminal pair being connected to said second end terminal, said hybrid feedback amplifier further comprising a second terminating resistor connected between one of said input terminal pair and said second end terminal, the other of said input terminal pair being connected to said additional tap.

Claim 12

A hybrid feedback amplifier as claimed in claim 1 wherein said amplifier section comprises a single stage transistor amplifier and said one terminal pair of said amplifier section comprises the base and emitter electrodes of said single stage transistor amplifier, said hybrid feedback amplifier further comprising a second terminating resistor connected across essentially the series combination of an output terminal pair of said amplifier section and said winding, and wherein said output terminal pair comprises the collector and emitter electrodes of said single stage transistor amplifier.