摘要:
First and second counters in a pulse width modulating circuit, whose respective outputs determine the trailing and leading edges of a pulse width modulated signal, count input clock pulses at a constant speed. The number of the pulses applied to the second counter during a cycle relative to the number of the pulses applied to the first counter is increased or decreased by one in response to a modulating pulse to change the counting phase of the second counter thereby changing the width of the pulse width modulated signal. Gates freeze the phases of the two counters at minimum and maximum pulse widths of the pulse width modulated signal to avoid abrupt jumps from minimum to maximum or vice versa.
摘要:
A method of simultaneously recording and reproducing a digital audio signal and a digital video signal for a dynamic picture. A digital signal is recorded and reproduced in N bits (N: integer), and an image area, an audio area and a control area are formed by part of the N bits. Compressed digital video signals for multiple screens forming a dynamic picture are allocated in the image area in each compression reference period. A digital audio signal in each compression reference period is allocated in the audio area in the compression reference period. Data, such as compression information, which concerns a digital signal to be allocated in the image area or audio area, is allocated in the control area. As a digital video signal carrying a vast amount of information is recorded in a compressed manner, and the compression information is recorded at the same time, recording and reproducing the digital video signal for a dynamic picture can be executed without problems.
摘要:
Digitally controllable ICs or function blocks in an electronic apparatus are connected through control bus lines, and a switch device is provided for disconnecting one of the digitally controllable ICs or function blocks from the control bus so that the control bus is not disabled when that one IC is turned off or is not occupied when the IC is operating in its internal processing mode. Therefore, communication between the remaining ICs can be maintained through the control bus.
摘要:
An integrated circuit device for an electronic equipment having an internal bus, the integrated circuit device comprising a plurality of input terminals, a switch circuit connected to the plurality of input terminals for selecting any one of a respective plurality of input signals via the plurality of input terminals, a switch control circuit for controlling the switch circuit to select any one of the input signals in dependence on a selection signal, an analog-to-digital converter for converting the selected input signal from the switch circuit into a corresponding serial digital signal, and a bus interface circuit connected to the internal bus for sending the serial digital signal from the analog-to-digital converter to the internal bus and for sending the selection signal from the internal bus to the switch control circuit.
摘要:
An apparatus for scrambling or encoding a television signal by inverting the latter signal in accordance with a control signal having a predetermined code pattern comprises a detector circuit for detecting a change in a picture scene of the television signal and generating an identification signal in response to detection of the scene change and code generator for generating a key code signal of specific pattern which indicates a particular program of the television signal. According to this invention, the control signal is formed in response to both the identification signal and the key code signal.
摘要:
A video recorder for automatically recording information being broadcast on at least one predetermined channel at a predetermined time comprises a tuner which tunes to any one of a plurality of channels received thereby and includes a channel selector actuable for selecting the predetermined channel, a recorder operable to record information broadcast on the channel to which the tuner is tuned, a timer actuable to cause operation of the recorder at the predetermined time, and a single, manually operable actuating member which simultaneously actuates the channel selector and the timer so that the recorder records the information broadcast on the predetermined channel at the predetermined time.
摘要:
This digital-analog converter receives a digital number and applies it to a counter capable of handling an n-bit binary capacity. When the counter counts to its full number, e.g. 1111 for a 4-bit capacity a writing signal generated in a control section causes the complement of the applied number to be written into the counter. The counter is then able to start counting from this complement number to the full (1111) number again. The control section then complements the written-in number back to the original number and counts up to the full number yet again. Thus, if the original binary number is 1100 and the reverse number, the counter counts 1100 and 0011 repetitively. At each count reversal, a flip-flop reverses, and a pulse corresponding in length to the original number is produced within each full count interval and that pulse is filtered by a low-pass filter to produce an analog signal corresponding to the original digital one.
摘要:
A method of and apparatus for tuning an AFT-controlled channel selecting apparatus of the type having a storage device for storing digital representations corresponding to predetermined channel frequencies from which a selected representation is read out and converted to a control voltage which is applied to a controllable tuning element included in an electronic tuner. When the control voltage is applied, generally it experiences a gradual increase in magnitude until its predetermined control voltage level is attained. The automatic fine tuning (AFT) circuit may pull in a frequency corresponding to the instantaneous level of the control voltage during the gradual increase in magnitude thereof. To avoid tuning the electronic tuner to such an unwanted pulled-in frequency, the AFT operation is carried out at a relatively slow rate when the tuning of the tuner approaches the frequency corresponding to the read out representation and then at a relatively fast rate when the tuner is tuned to a frequency that deviates from the desired frequency within a predetermined range.
摘要:
A channel indicator device is disclosed in which a tuner for achieving station selection between VHF and UHF band television broadcastings is provided in association with a single channel selection shaft of the tuner, a switch for band selection is also provided in connection with the channel selection shaft, and an indicator in the type of a plural-unit indication is provided, the indicator having a numeral corresponding to a selected channel in response to the channel selection and a code corresponding to a selected one of the VHF and UHF bands. The indicator has provided with a plural-unit indication member consisting of a plurality of indication elements to form a numeral "8".
摘要:
A digital control system for electronic apparatus employs an internal bus system and includes at least one master controller and a plurality of operational circuits connected via control bus lines so that, during normal operation of the electronic apparatus, the master controller can carry out predetermined control operations relative to the respective circuit blocks. During testing and/or adjustment, an auxiliary master control circuit is connected to the control bus lines in order to control the operational circuitry in place of the master control circuit, while holding the master control in the slave mode.