Automatic peaking circuit

Claim 2

An automatic frequency compensation apparatus for maintaining a predetermined amount of high frequency content in a video signal comprising: a. a video amplifier having an input terminal for receiving said video signal and an output terminal, said amplifier having a selectable gain frequency response; b. means for sampling the high frequency content of a signal at said output terminal; and c. control means for changing the slope of the gain-frequency response of said amplifier, said control means being operatively connected to said means for sampling whereby a decrease in the amount of high frequency content at said amplifier output terminal will cause the slope of said amplifier gain-frequency response to increase positively.

Claim 3

The apparatus of claim 1 wherein said slope of said amplifier gain frequency response is less for signals representing white detail than signals representing gray detail.

Claim 4

An automatic frequency compensation apparatus for maintaining a predetermined amount of high frequency content in a video signal which comprises: a. an amplifier for supplying a video signal; b. a control means for varying the slope of the gain-frequency response of said amplifier, said control means being activated by a d.c. voltage; c. a high pass filter for filtering a video signal supplied by said amplifier; and d. a video signal detector for receiving a signal supplied by said high pass filter, said detector providing a d.c. voltage for activating said control means whereby the gain-frequency response of said amplifier is modified in response to the high-frequency signals at said amplifier output terminal.

Claim 5

An automatic frequency compensation apparatus for maintaining a predetermined amount of high frequency content in a video signal which comprises: a. an amplifier for supplying a video signal; b. a control means for varying the slope of the gain-frequency response of said amplifier, said control means being activated by a d.c. voltage; c. a high pass filter for filtering a video signal supplied by said amplifier; and d. a video signal detector for receiving a signal supplied by said high pass filter, said detector providing a d.c. voltage for activating said control means whereby the gain-frequency response of said amplifier is modified in response to the high-frequency signals at said amplifier output terminal.

Claim 6

An automatic peaking apparatus for enhancing television picture resolution which comprises: a. a transistor amplifier having a base circuit for receiving a video signal containing said television receiver picture information, a collector circuit for supplying a video signal, and an emitter circuit; b. a first capacitor; c. A voltage variable capacitor connected in series with said first capacitor, said series combination being connected in parallel with said amplifier emitter circuit; d. a video signal detector for providing a d.c. voltage to said variable capacitor; and e. a high pass filter for providing a signal from said amplifier collector circuit to said video signal detector whereby said amplifier gain-frequency response is modified according to the amount of high frequency signals at the collector circuit of said amplifier.

Claim 7

An automatic peaking apparatus for enhancing television picture resolution which comprises: a. a transistor amplifier having a base circuit for receiving a video signal containing said television receiver picture information, a collector circuit for supplying a video signal, and an emitter circuit; b. a first capacitor; c. A voltage variable capacitor connected in series with said first capacitor, said series combination being connected in parallel with said amplifier emitter circuit; d. a video signal detector for providing a d.c. voltage to said variable capacitor; and e. a high pass filter for providing a signal from said amplifier collector circuit to said video signal detector whereby said amplifier gain-frequency response is modified according to the amount of high frequency signals at the collector circuit of said amplifier.

Claim 8

The apparatus of claim 4 further comprising a means for removing a 3.58 MHz signal from said amplifier output signal.

Claim 9

The apparatus of claim 5 wherein the means for removing said 3.58 MHz signal comprises a parallel tuned circuit having a resonant frequency substantially at the color subcarrier frequency connected in series with said transistor amplifier emitter circuit.

Claim 10

The apparatus of claim 4 wherein said video signal detector comprises: a. a transistor having an emitter terminal, a base terminal, and a collector terminal; b. a capacitor having a first end connected to said collector terminal; and c. means for supplying a voltage between said capacitor second end and said emitter terminal.

Claim 11

An automatic frequency compensation apparatus for enhancing television picture resolution comprising: a. a source of video signals containing television picture information; b. a transistor having base, emitter, and collector terminals, said base terminal being operatively connected to said source of video signals; c. a voltage variable impedance having first and second terminals, said impedance first terminal being connected to said emitter terminal; d. a load impedance having a first and second terminal, said first terminal being connected to said collector terminal; e. a high pass filter for receiving a signal from said transistor collector terminal; f. an a.c. signal detector for receiving an output signal from said high pass filter, said signal detector having a d.c. output voltage operably connected to said voltage variable impedance; and g. means for supplying a d.c. voltage between said collector impedance second terminal and said voltage variable impedance second terminal.

Claim 12

An automatic frequency compensation apparatus for enhancing television picture resolution comprising: a. a source of video signals containing television picture information; b. a transistor having base, emitter, and collector terminals, said base terminal being operatively connected to said source of video signals; c. a voltage variable impedance having first and second terminals, said impedance first terminal being connected to said emitter terminal; d. a load impedance having a first and second terminal, said first terminal being connected to said collector terminal; e. a high pass filter for receiving a signal from said transistor collector terminal; f. an a.c. signal detector for receiving an output signal from said high pass filter, said signal detector having a d.c. output voltage operably connected to said voltage variable impedance; and g. means for supplying a d.c. voltage between said collector impedance second terminal and said voltage variable impedance second terminal.

Claim 13

The apparatus of claim 8 further comprising a second transistor having a base, an emitter, and collector; said second transistor base being connected to said first transistor collector, said second transistor collector being connected to said means for supplying a d.c. voltage, and said second transistor emitter terminal being connected to said high pass filter input terminal; and a resistor, said resistor being connected from said second transistor emitter to said means for supplying a d.c. voltage.