Goldstar, Co., Ltd.

Young G Oh

A control apparatus of a real time counter for a video cassette recorder. This apparatus comprises a CLOG detection section having an envelope detector, a comparator, and a low-pass filter for detecting a CLOG signal to judge whether a signal exists on the videotape; an ATF detection section having an ATF detector, an analog-to-digital converter, a band comparator, a shift register, and a state detector for detecting an automatic track following signal, an AND gate for performing a logical product between the CLOG signal and the automatic track following signal and an REC instruction; and a counting section having a switch which is for controlling a real time counter using the output, or a control signal of the AND gate. This apparatus accomplishes the accurate control of a counting by using an automatic track following signal as well as the CLOG signal.

Control apparatus of a real time counter for a video cassette recorder

A circuit for controlling a speed and a phase of a VCR servo system includes a Control (CTL) signal generation section, a speed error detection section, a phase error detection section and a speed/phase control section. The phase error detection section has a recording phase error detector and a playback phase error detector. A CTL signal blank discrimination section inputs a CTL pulse from the playback phase error detector, discriminates a blank interval of a CTL signal based on the inputted CTL pulse, and outputs discrimination signal in accordance with the discriminated result. A first switching control section inputs the discrimination signal, an FF/REW mode signal, a recording mode signal and a tape type discriminating signal and performs a logical operation based on the inputted signals to output a first control signal. A second switching control section inputs a video tape loading signal, the FF/REW mode signal and the tape type discriminating signal and performs a logical operation based on the inputted signals to output a second control signal. A first switching section is operative in response to the first control signal and a second switching section is operative in response to the second control signal.

Circuit and method for controlling speed and phase of VCR servo system

A rotation control apparatus employing a comb filter to cut off a specified frequency and multiples thereof in response to speed error data detected from a rotation detector. A phase error detector detects a phase error between the rotation detector and an external vertical synchronization pulse. A differentiator converts the output of the filter into angular acceleration error data. The output of the phase error detector is integrated. The two values are scaled and converted to an analog signal which is utilized to drive a motor.

Rotation control apparatus employing a comb filter and phase error

A motor rotation controlling device, usable for example in a video recorder, to minimize transient phenomena at an initial operation and shorten a transient response time for detecting a rotation speed of a motor, a signal processor for constantly controlling rotation speed of the motor by the detected rotation speed supplied from the rotation detector, a comb-shaped filter for removing a rotation period component and its harmonic component included in a control signal supplied from the signal processor, a controller for varying a transfer function of the comb-shaped filter at a transient response time and a normal time according to the rotation speed of the motor, a driving device for driving a motor by the filtered control signal supplied from the comb-shaped filter, and a limit device connected between the signal processing means and the comb-shaped filter for clamping the control signal.

Motor rotation controlling device

In a VCR including a timer microprocessor for counting capstan frequency signals or reel pulses from a VCR mechanism and a system control unit for communicating with the timer microprocessor and supplying predetermined signals to the VCR mechanism and a servo system, a method for executing predetermined assembly programs adapted to assembly edit several recorded programs according to the order desired and inserting titles in respective recorded programs. In order to carry out title inserting for respective recorded programs during execution of predetermined assembly programs, a memory is provided which is adapted to store data corresponding to the assembly programs and titles of recorded programs, in accordance with the control of timer microprocessor. In accordance with the method and apparatus, titles can be automatically and conveniently inserted in respective recorded programs during the execution of predetermined assembly programs, thereby avoiding any poor screen quality caused by repeated playback and recording of programs.

Method and apparatus for automatically inserting titles for video

A quantizing error removing circuit for a rotational control device applied to a servo circuit and the like of a video cassette recorder, designed to removing the quantizing error generated upon controlling the speed and phase, minimizing a change of gain characteristic of a control device, thereby improving its efficiency. The circuit according to the present invention includes a moving average filter which comprises a predetermined number of delay elements connected in series to each other in order to delay by a predetermined set time, a phase error control signal outputted from a phase control filter; a summer for summing the phase error control signal and each output of the delay elements; a divider for dividing a summed output value of the summer by the number of summing signals, thereby outputting the divided quotient as a phase control signal; and another delay element for delaying the remainder value outputted from the divider by a predetermined set time, thereby feeding the remainder value back to the summer. The remainder value fed back from said other delay element to the summer is summed with the summed value of the summer at the next sampling time point, and according to this, generation of quantizing error caused by the presence of the remainder value is prevented.

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Seoul, South Korea

Young G Oh