Detecting horizontal blanking time in cathode ray tube devices

A method for generating a timing pulse for use in a cathode ray tube monitor including a first inductor that is a flyback inductor comprising the step of:

• detecting electrical pulses produced across a second inductor placed in series with a retrace capacitor in a horizontal deflection circuit of said cathode ray tube monitor that are generated as the direction of current flow changes through said retrace capacitor;
• and
• generating said timing pulse in response to said electrical pulses.

A method for generating precisely timed electrical pulses in a cathode ray tube monitor including a first inductor that is a flyback inductor comprising the steps of:

• placing a second inductor in series with a retrace capacitor in a horizonal deflection circuit;
• detecting said electrical pulses produced across said second inductor that are generated as the direction of current flow changes through said retrace capacitor.

A method for generating precisely timed electrical pulses in a cathode ray tube monitor comprising the steps of:

• storing a predetermined amount of energy in a bead inductor placed in the current path of a retrace tuning capacitor in said cathode ray tube monitor;
• detecting electrical pulses generated across said bead inductor as said predetermined amount of energy is stored in said bead inductor;
• detecting electrical pulses generated across said bead inductor as said stored energy is released by said bead inductor.

The method of claim 19 further comprising the steps of:

• generating a control signal using a logic circuit to decode said electrical pulses generated as energy is stored in and released by said bead inductor;
• using said control signal to control the operation of video amplifiers in said cathode ray tube monitor.

An apparatus for reducing left side ringing distortion in a cathode ray rube horizontal deflection circuit comprising:

• an inductor disposed in said cathode ray tube horizontal deflection circuit in series with a retrace turning capacitor, said inductor having an inductance that causes said inductor to saturate before full yoke current.

A method for reducing left side ringing distortion in a cathode ray tube horizontal deflection circuit comprising the steps of:

• placing a bead inductor of predetermined value, such that said bead inductor saturates before full yoke current, in the current path of a retrace tuning capacitor and a dampening diode disposed in said cathode ray tube horizontal deflection circuit, whereby said bead inductor lowers the circuit resonant frequency.

An apparatus for generating blanking signals in a cathode ray tube horizontal deflection circuit including first inductor means that include a flyback inductor, said apparatus comprising:

• second inductor means disposed in series with a retrace tuning capacitor for generating precisely timed voltage pulses;
• and
• means for generating said blanking signals in response to said precisely timed voltage pulses.

An apparatus for reducing left side ringing distortion in cathode ray tube horizontal deflection circuits comprising:

• inductor means that saturates before full yoke current for lowering the resonant frequency of a circuit containing a damper diode and a retrace tuning capacitor that forms a part of a cathode ray tube horizontal deflection circuit.

An apparatus for generating timing pulses for use in a cathode ray tube monitor comprising:

• an inductor disposed in series with a retrace tuning capacitor of a deflection circuit of said cathode ray tube monitor that has a size sufficient to cause said timing pulses to be generated across said inductor to indicate a position of a horizontal retrace, a first of said timing pulses rising and falling across said inductor during a single charging time of said retrace tuning capacitor;
• circuitry that utilizes said timing pulses.

A method for generating a precisely timed voltage pulse in a horizontal deflection circuit including a damper diode, said method comprising:

• placing an inductor in series with a retrace tuning capacitor, such that said inductor and said retrace tuning capacitor are in parallel with said damper diode;
• detecting a voltage pulse across said inductor produced by current flowing through said inductor and said retrace tuning capacitor.

An apparatus for generating a control signal in response to a first precisely timed electrical pulse produced in a cathode ray tube horizontal deflection circuit, said apparatus comprising:

• an inductor placed in series with a retrace tuning capacitor that produces a precisely timed electrical pulse that rises and falls across said inductor substantially coincident with the beginning of a horizontal retrace;
• and
• decoder circuitry triggered by said precisely timed electrical pulse detected across said inductor to generate said control signal.

An apparatus for generating a precisely timed voltage pulse in a horizontal deflection circuit comprising:

• an inductor placed in series with a retrace tuning capacitor, such that said inductor and said retrace tuning capacitor are in parallel with said damper diode;
• and
• detector circuitry that detects a voltage pulse across said inductor produced by a change in current flowing through said inductor and said retrace tuning capacitor.