摘要:
An AFT circuit for a television receiver automatically adjusts the frequency of a tuner local oscillator, not only on the basis of an error signal provided from an AFT discriminator, but also on the basis of horizontal synchronizing pulses contained in the video signal to which the receiver is tuned. A synch signal detector detects the presence or absence of the synchronizing pulses. A control circuit provides a control signal to the local oscillator in response to the AFT error signal when the latter is above or below a reference voltage such that the desired frequency is within an AFT capture range. However, when the AFT signal is at the reference voltage, the control circuit provides the control signal based on the presence or absence of the synchronizing pulses, such that when the pulses are present, the local oscillator frequency is raised, but when the pulses are absent, the local oscillator frequency is lowered. Then, when the AFT signal is present, the local oscillator is controlled thereby. This AFT circuit has an expanded effective capture range, and is prevented from locking onto the sound carrier of an adjacent channel. 00202
摘要:
An arrangement and a method for testing various kinds of electronic equipment, each having an internal bus, during assembly and during subsequent servicing, wherein a plurality of software packages, each storing instructions and data pertinent to the testing and adjustment of a specific kind of equipment are prepared and a computer is connectable in common to the various kinds of equipment via their internal buses for testing any one of the various equipments according to the contents of the appropriate software package.
摘要:
This invention relates to an apparatus for descrambling scrambled television signals including a scrambled video signal having a first scrambling pattern, a scrambled control signal having a second scrambling pattern, and descrambling signals.
摘要:
A color information display apparatus includes a common memory of an integrated circuit configuration for storing both pattern data and color data describing an attribute of the corresponding pattern data to be displayed on a CRT, the common memory including a first address area for the pattern data and a second, different address area for the color data, a circuit for generating address signals for the common memories in response to the scanning position of the electron beam on the screen of the CRT, a parallel-serial converting circuit for converting parallel pattern data in the common memory to serial data, a first latch circuit for latching the color data in the common memory to produce an output color signal, a circuit for generating a color information signal from the serial data from the parallel-serial converting circuit and the output signal from the first latch circuit, an address selector connected between the address signal generating circuit and the common memory, the first address area and the second address area of the common memory being addressed alternatively by the address selector, and a second latch circuit connected between the common memory and the serial-parallel converting circuit for latching the pattern data supplied to the latter circuit.
摘要:
In a channel selecting apparatus for a television receiver having an electronic tuning tuner for changing the receiving frequency in accordance with an analog control signal applied thereto; a memory has a plurality of addresses for storing respective digital codes each identifying a respective channel, and such addresses in the memory are selectively activated so as to effect read out of the respective channel identifying digital code to a digital-to-analog converter which converts the same into a respective analog control signal for the tuner. Deviation of the receiving frequency, as established in response to the analog control signal, from the correct receiving frequency for the channel identified by the digital code then being read out of the memory is detected, and in response to a detected deviation the ditial code being received by the digital-to-analog converter is automatically modified or changed in the sense for removing said deviation and thereby effecting a fine tuning operation. In a preferred embodiment, when the detected deviation of the established receiving frequency from the correct receiving frequency exceeds a predetermined amount, the resulting modified digital code is stored in the memory in place of the read out digital code resulting in such deviation, thereby to ensure that the stored digital codes will not, with time, result in respective receiving frequencies that are outside the pull-in range of the automatic fine-tuning operation.
摘要:
A TV channel indicator is disclosed where the channel numbers 1 to 9 are indicated substantially in the center part of the indicator, which also coincides with that of the channel numbers 10 to 99.
摘要:
A method can record or reproduce a digital audio signal and a digital video signal simultaneously. An N-bit (N: positive integer) digital audio signal is positioned at a higher bit side and an M-bit (M: positive integer) digital video signal is positioned at a lower bit side so as to form an (N+M)-bit digital signal which is recorded or reproduced in this condition. Since the digital video signal is positioned at the lower bit side, the digital video signal may not affect the reproduced audio signal even if the (N+M)-bit digital signal is processed as the digital audio signal in the reproducing process.
摘要翻译:一种方法可以同时记录或再现数字音频信号和数字视频信号。 N位(N:正整数)数字音频信号位于较高位侧,M位(M:正整数)数字视频信号位于较低位侧,以形成(N + M )位数字信号,在这种状态下被记录或再现。 由于数字视频信号位于较低位侧,所以即使在再现处理中将(N + M)位数字信号作为数字音频信号进行处理,数字视频信号也可能不影响再现的音频信号。
摘要:
A control system for an electronic apparatus, such as a television receiver, having a control circuit with a control program in an internal memory sequentially communicates over an internal bus within predetermined intervals, such as within the vertical blanking interval of the television signal, with a plurality of controllable circuits in the television receiver, and the control circuit operates to select and communicate with a specific, selected one of the controllable circuits first, in each predetermined interval, with the remainder of the controllable circuits being subsequently communicated with in the remaining portion of the vertical blanking interval.
摘要:
A television signal transmission system transmits a television signal having a polarity inverted portion in association with a scene change and a polarity inverted portion after a predetermined time interval independently of the scene change.
摘要:
Digital data transfer in a digital television receiver between an internal central processing unit, or an external computer, and the video/audio processing circuitry by way of an internal bus is accomplished efficiently and without producing noise interference by using a high-frequency clock signal and a relatively low-frequency clock signal at different times. The high-frequency signal would normally produce visually perceptable noise, however, it is employed only during vertical blanking intervals, and the low-frequency clock signal, which would not produce visually perceptable noise, is used at all times other than the vertical blanking intervals, whereby noise interference that would be otherwise seen on the visual display of the television receiver is suppressed.