System for generating 2H pulses in a television receiver

Claim 2

In a television receiver which develops a color subcarrier signal, a system for generating 2H pulses, comprising: means providing a plurality of reference signals whose frequencies are related to the frequency for the color subcarrier; means for counting cycles of the reference signals; control means coupled to said counting means for generating an output pulse after each time the counting means reaches a preselected integral count, each of the output pulses being coupled for clearing the counting means so that the next successive count thereof occurs after a mixed number of reference signal cycles for generating successive ones of the output pulses at a rate equal to twice nominal horizontal scan rate; and means for sequentially coupling the reference signals to the counting means such that the counting means receives a different reference signal in response to each of the output pulses, whereby the output pulses constitute said 2H pulses.

Claim 3

A system as set forth in claim 1 wherein said plurality of reference signals comprise first, second, third and fourth reference signals, each having a frequency equal to the frequency of the color subcarrier signal, the first reference signal having a given phase, the second reference signal having a phase which is offset by ninety degrees from the phase of the first reference signal, the third reference signal having a phase which is offset from the phase of the second reference signal by ninety degrees, and the fourth reference signal having a phase which is offset from the phase of the third reference signal by ninety degrees.

Claim 4

A system as set forth in claim 2 wherein said integral count comprises 112, and said mixed number comprises 1.75.

Claim 5

A system as set forth in claim 1 wherein said plurality of reference signals comprise two oppositely phased reference signals, each reference signal having a frequency equal to twice the frequency of the color subcarrier signal.

Claim 6

A system as set forth in claim 4 wherein said integral count comprises 226, and said mixed number comprises 1.5.

Claim 7

A system as set forth in claim 1 wherein said means for sequentially coupling the reference signals to the counting means includes a plurality of gates, each receiving one of the reference signals and each responsive to a different binary signal for coupling its received reference signal to the counting means, and means responsive to said counting means reaching said preselected integral count for developing a different one of the binary signals to enable a respective one of said gates.

Claim 8

A system as set forth in claim 6 wherein said control means includes a decoder for generating an output responsive to each time the counting means reaches said integral count, and a flip-flop receiving the decoder's output for generating said output pulses.

Claim 9

A system as set forth in claim 7 wherein said means for developing binary signals includes an AND gate receiving the reference signal coupled to the counting means and enabled by the decoder's output, and a counter clocked by said AND gate.

Claim 10

In a television receiver which develops a color subcarrier signal, a system for generating 2H pulses, comprising: means providing first, second, third, and fourth reference signals whose frequencies are equal to the frequency of the color subcarrier, the first reference signal having a given phase, the second reference signal having a phase which is offset by ninety degrees from the phase of the first reference signal, the third reference signal having a phase which is offset from the phase of the second reference signal by ninety degrees, and the fourth reference signal having a phase which is offset from the phase of the third reference signal by ninety degrees; means for counting cycles of the reference signals; a decoder for developing an output in response to each time the counting means reaches a preselected, integral count; a flip-flop receiving the decoder's outputs and clocked by a reference signal received by said counting means for generating a plurality of output pulse each being coupled for clearing the counting means such that the next successive count thereof occurs after a mixed number of reference signals cycles for generating successive ones of said output pulses at a rate equal to twice nominal horizontal scan rate; an AND gate enabled by the decoder's output and receiving the reference signal applied to the counting means; a counter responsive to four successive outputs from the AND gate for successively developing four different binary signals; and gate means receiving the binary signals and the four reference signals for outputting to the counting means a different reference signal each time a different binary signal is received, whereby the reference signals are counted sequentially such that the output pulses developed by said flip-flop correspond to said 2H pulses.

Claim 11

In a television receiver which develops a color subcarrier signal, a system for generating 2H pulses, comprising: means providing first, second, third, and fourth reference signals whose frequencies are equal to the frequency of the color subcarrier, the first reference signal having a given phase, the second reference signal having a phase which is offset by ninety degrees from the phase of the first reference signal, the third reference signal having a phase which is offset from the phase of the second reference signal by ninety degrees, and the fourth reference signal having a phase which is offset from the phase of the third reference signal by ninety degrees; means for counting cycles of the reference signals; a decoder for developing an output in response to each time the counting means reaches a preselected, integral count; a flip-flop receiving the decoder's outputs and clocked by a reference signal received by said counting means for generating a plurality of output pulse each being coupled for clearing the counting means such that the next successive count thereof occurs after a mixed number of reference signals cycles for generating successive ones of said output pulses at a rate equal to twice nominal horizontal scan rate; an AND gate enabled by the decoder's output and receiving the reference signal applied to the counting means; a counter responsive to four successive outputs from the AND gate for successively developing four different binary signals; and gate means receiving the binary signals and the four reference signals for outputting to the counting means a different reference signal each time a different binary signal is received, whereby the reference signals are counted sequentially such that the output pulses developed by said flip-flop correspond to said 2H pulses.

Claim 12

A system as set forth in claim 9 wherein said integral count comprises 112 and said mixed number comprises 1.75.

Claim 13

A system as set forth in claim 10 wherein said gate means includes: four AND gates each receiving a different reference signal and each responsive to a different binary signal from said counter; and an OR gate coupled to the output of each AND gate and coupled to a clock input of said counting means.

Claim 14

In a television receiver which develops a color subcarrier signal, a system for generating 2H pulses, comprising: means providing first, second, third and fourth reference signals whose frequencies are equal to the frequency of the color subcarrier, the first reference signal having a given phase, the second reference signal having a phase which is offset by ninety degrees from the phase of the first reference signal, the third reference signal having a phase which is offset from the phase of the second reference signal by ninety degrees, and the fourth reference signal having a phase which is offset from the phase of the third reference signal by ninety degrees; four signal coupling gates each receiving a different one of the reference signals and each responsive to a different binary signal for sequentially outputting its received reference signal; an OR gate coupled to the outputs of said signal coupling gates; a first counter coupled to the output of the OR gate for counting cycles of the reference signals; a decoder responsive to each time the first counter reaches a count of 112 for developing an output; a flip-flop having a data input receiving the decoder's output, a clock input receiving the output of the OR gate, and an output for clearing the first counter for an interval equal to 0.75 cycles of a reference signal; an AND gate receiving the output of the OR gate and receiving the output of the decoder; a second counter for successively developing four different binary signals in response to four successive outputs from the AND gate; and means for coupling said binary signals to said signal coupling gates, whereby cycles of the four reference signals are counted such that the output of said flip-flop corresponds to said 2H pulses.

Claim 15

In a television receiver which develops a color subcarrier signal, a system for generating 2H pulses, comprising: means providing first, second, third and fourth reference signals whose frequencies are equal to the frequency of the color subcarrier, the first reference signal having a given phase, the second reference signal having a phase which is offset by ninety degrees from the phase of the first reference signal, the third reference signal having a phase which is offset from the phase of the second reference signal by ninety degrees, and the fourth reference signal having a phase which is offset from the phase of the third reference signal by ninety degrees; four signal coupling gates each receiving a different one of the reference signals and each responsive to a different binary signal for sequentially outputting its received reference signal; an OR gate coupled to the outputs of said signal coupling gates; a first counter coupled to the output of the OR gate for counting cycles of the reference signals; a decoder responsive to each time the first counter reaches a count of 112 for developing an output; a flip-flop having a data input receiving the decoder's output, a clock input receiving the output of the OR gate, and an output for clearing the first counter for an interval equal to 0.75 cycles of a reference signal; an AND gate receiving the output of the OR gate and receiving the output of the decoder; a second counter for successively developing four different binary signals in response to four successive outputs from the AND gate; and means for coupling said binary signals to said signal coupling gates, whereby cycles of the four reference signals are counted such that the output of said flip-flop corresponds to said 2H pulses.