Abstract: A rotation stopping apparatus for a motor comprises a frequency signal generating circuit for generating a signal having a frequency according to a rotational speed of a motor, a voltage forming circuit for forming a voltage according to the frequency of the frequency signal from the frequency signal generating circuit, a motor driving circuit for supplying a forward direction current to the motor upon rotation of the motor and supplying a reverse direction current to the motor when the rotation of the motor is stopped to perform a damping operation with respect to the rotation of the motor, a detecting circuit for detecting that a voltage from the voltage forming circuit has become below a predetermined threshold voltage, and an interrupting circuit for interrupting the supply of the reverse direction current to the motor by the motor driving circuit according to the detected result obtained from the detecting circuit.

Abstract: In a color television receiver adapted to receive a color television signal containing vertical interval reference (VIR) signals, a VIR correction circuit is provided to automatically control the hue and color saturation of the received broadcast signal, which may also be coupled to a video tape recorder of the type in which adjacent field signals are recorded with their respective record tracks being skewed relative to each other to permit elimination of otherwise required guardbands between adjacent field tracks. The recorded video signal is reproduced by mixing adjacent horizontal line signals to reduce crosstalk level. A disabling circuit is provided to disable the VIR correction circuit when the receiver is switched to the output of the video tape recorder in playback mode to prevent false VIR signals due to the mixing from affecting the reproduced colors.

Abstract: In a color signal reproducing circuit, a red color difference signal from a color demodulator circuit is corrected by a blue color difference signal, and the blue color difference signal is corrected by a luminance signal. The phase of a color subcarrier signal to be supplied to the color demodulator circuit is controlled by the corrected red color difference signal during reception of a VIR signal, and the level of a color signal to be supplied to the color demodulator circuit is controlled by the corrected blue color difference signal. The controls of hue and color saturation are facilitated by the use of the corrected color difference signals. It is also made possible to deliver from the color demodulator circuit, color difference signals which match the fluorescence characteristics of a color picture tube.

Abstract: A tint control circuit for color television receivers includes a voltage-controlled oscillator for locally generating a color subcarrier, a variable phase shifter shifting the phase of the generated subcarrier in dependence on a manually adjusted DC control voltage, and a phase detector which allows a received color burst to be supplied to a load circuit in dependence on the difference in phase between the color burst and the DC-controlled, variable phase-shifted subcarrier in order to derive a DC control voltage from the load circuit which controls the voltage-controlled oscillator.

Abstract: Two terminals of a variable resistor are respectively connected via resistors to bases of two transistors which constitute an input stage of a differential amplifier while the movable contact of the variable resistor is fed with a predetermined voltage. Either the resistance of the variable resistor with respect to the resistances of fixed resistors connected to the bases or the ratio between the fixed resistors is so selected that the variation of the maximum resistance of the variable resistor does not influence the relationship between the position of the movable contact and the gain of the differential amplifier.

Abstract: In a subcarrier regeneration circuit for color television receivers, a phase detector output is sampled by a signal sample-and-hold circuit and a bias sample-and-hold circuit to develop a voltage between the outputs of the two sample-and-hold circuits to control the frequency of a 3.58 MHz subcarrier generated by a voltage controlled oscillator. The oscillator output is phase shifted by 90.degree. and applied to one input of the phase detector for comparison with a gated color burst. The signal sample-and-hold circuit samples the phase detector output during the interval of the color burst, while the bias sample-and-hold circuit samples the phase detector output during an interval which is substantially equal to the flyback interval minus the color burst interval.

Abstract: A variable frequency oscillator comprises an oscillating loop and a variable phase shifter for imparting one of two different phase shifts depending upon the polarities of a DC control voltage to a signal from the oscillating loop. The phase-shifted signal has its amplitude controlled by the amplitude of the control voltage and is combined with the signal in the oscillating loop. The vector sum of the combined signals determines the phase angle of the oscillator signal and hence the frequency thereof.