Sony Corporation

Hodogaya Chemical Co., Ltd.

Nippon Aerosil Co., Ltd.

Hisao Okada

Takao Mogi

Shigetoshi Murakami

Yoshio Ishigaki

Hideyuki Otsuka

Susumu Yoshida

Masaki Okubo

Yoshikazu Aoki

Seiji Kawaberi

Yuki Amano

Seiichiro Tanaka

Naohiro Naito

Provided by the present invention is a surface-modified silica powder, characterized in that the said powder is obtained by surface treatment of a silica powder with one or two or more of a compound (A) and with an aminosilane (B), wherein the fixing rate of the compound (A) and the aminosilane (B) is a total of 50% or more, the hydrophobic rate is 80% or more, and the triboelectrostatic charge amount is 200 &#x3bc;C/g or less in its absolute value. The surface-modified silica powder of the present invention can stabilize many properties including fluidity and electrostatic properties while can significantly reduce problems such as fogging and decrease in image quality without significantly deteriorating characteristics of a developing agent and so forth when this is used as an external additive.

Surface-modified silica powder and method for producing the same, as well as toner composition for electrophotography

A television receiver for receiving standard television channel signals and a scrambled television channel signal includes a channel selector which selects one of the television channel signals, a tuner which tunes the selected television channel signal, and a converting circuit which converts the scrambled television channel signal to a vacant standard television channel signal for tuning by the tuner.

Television signal receiving system

A remote control apparatus having a commander and a receiver. In a wireless remote control system for a television receiver having a channel command device and a responding device, the channel command device includes a channel selecting circuit for selecting one channel command from among a plurality of predetermined channel commands, a command signal generating circuit for generating a channel command signal corresponding to a selected channel command, and a channel command transmitting circuit having a speaker for transmitting the channel command signal; and the responding device includes a channel command receiving circuit having a microphone for receiving the transmitted channel command signal and a channel command discriminating circuit for discriminating the channel command signal and supplying a channel selecting signal corresponding to the discriminated channel command signal to control a tuning circuit of the television receiver. Further, there is provided in the responding device, a return signal generating circuit for producing a return signal corresponding to the channel command indicated by the channel selecting signal and a return signal transmitting circuit having a speaker for transmitting the return signal, while the channel command device further has a return signal receiving circuit having a microphone for receiving the transmitted return signal, a return signal discriminating circuit for discriminating the return signal and producing a discriminated return signal indicating the channel command to which the return signal corresponds, a comparing circuit for comparing the originally selected channel command and the discriminated return signal, and an indicating circuit connected to the comparing circuit for indicating a coincidence of the originally selected channel command and the discriminated return signal.

Remote control apparatus

A muting circuit for a television receiver of the type having a tuner which is operative to select a desired channel in accordance with a channel selection operation to produce a channel select signal representing the selected channel, a detector circuit for detecting whether a video signal is present or not, a muting signal generator circuit supplied with an output from the detector circuit and the channel select signal representing the selection of a predetermined channel to produce a muting signal when the predetermined channel is selected but no output is produced by the detector circuit, and a muting circuit coupled to a low frequency signal transmission path in response to the muting signal from the muting signal generator circuit to cut off or attenuate the transmission of a low frequency signal.

Muting circuit for a television receiver

A remote control apparatus is constituted by a command encoding device and a command decoding device. In the command encoding device, a timing pulse generator indicates the beginning and end of a time interval of a length which is a function of a command to be encoded, a pulse of the first duration shorter than said time interval is initiated in response to said beginning of the time interval, a pulse of a second duration different from said first duration and shorter than said time interval is initiated in response to said end of the time interval, and said pulses of said first and second duration respectively, are sequentially transmitted in the command decoding device, upon the receipt of a pulse of said first duration followed by a pulse of said second duration, a first indication is produced in response to the receipt of said pulse of the first duration and a second indication is produced in response to the receipt of said pulse of the second duration, and a device provides a value which varies as a function of the length of time between each said second indication which immediately precedes it, whereupon, a command signal is produced as a function of said value.

Remote control system

A digital tuning receiver having an electrically tuneable tuner and an AFT circuit is driven in a unidirectional sweep by the D/A converted output of a reversible counter. The reversible counter continues to count input pulses, and the unidirectional sweep continues until stopped by the reception of a signal which produces a first signal from an AFT frequency discriminator followed within a predetermined time by a second signal of opposite polarity from the AFT frequency discriminator. The number stored in the stopped reversible counter may be further adjusted by AFT signals and stored for later recall. If the second signal is not received within a predetermined time, as occurs with spurious beat signals, the sweep is not stopped but continues until a proper signal is received.

Receiver

In a channel selecting apparatus for a television receiver having a tuner with a voltage-controlled, variablereactance device as its tuning element, and in which such tuning element has a non-linear relation between its control voltage and the resulting receiving frequency; a sweep pulse generator is operable for producing sweep pulses, a counter counts the sweep pulses for producing progressively changing binary codes corresponding to the changing counts of the counter and which represent respective control voltages for the variable reactance device, a digital-to-analog converter receives the binary codes and converts the same into the respective control voltages for the variable reactance device, and a circuit is provided for varying the period of the sweep pulses so that the rate of change of the receiving frequency is substantially uniform over the range of the progressively changing binary codes. Such circuit for varying the period of the sweep pulses is preferably operable by the binary codes so as to respond to the changes in the latter.

Channel selecting apparatus with linearized tuning

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 is provided with a plurality of addresses at which respective digital codes each intended to identify a respective broadcast channel are selectively stored or written in a programming mode of the apparatus, and, in a channel selecting mode of the apparatus, a selected channel identifying digital code is read out of the memory to a digital-to-analog converter which converts the same into a respective analog control signal for tuning the tuner to a receiving frequency. Any deviation of the receiving frequency, as established in response to the analog control signal, from the transmitting frequency for the channel identified by the digital code then being read out of the memory is detected, and in response thereto the digital code being applied to the digital-to-analog converter is modified or changed in the sense for removing the deviation and thereby effecting a fine tuning operation. When, in the channel selecting mode, the detected deviation of the established receiving frequency from the transmitting frequency exceeds a predetermined amount, the resulting modified digital code may be automatically stored or rewritten in the memory in place of the read out digital code resulting in such deviation. The writing of digital codes in the memory in the programming mode and the rewriting of modified digital codes in the memory in the channel selecting mode are permitted only if, at the time of such writing or rewriting, there is being received a broadcast signal with a transmitted frequency corresponding to the receiving frequency established by the digital code to be written or rewritten in the memory.

Channel selecting apparatus with automatic rewriting of channel

A tuning system for digitally controlled electronically tuned tuner with automatic fine tuning (AFT) constantly operable to hold the tuner at a predetermined optimum frequency setting, especially a television channel. A reversible counter provides the digital signal to control the tuning of the tuner and is, itself, deliberately shifted from one setting to another by pulses from a source, such pulses being applied to the UP input terminal of the counter as the up-tuning pulses to shift the tuner frequency higher. Pulses from the same source are also used as down-tuning pulses when applied to the DOWN input terminal of the tuning pulses to a lower frequency supplied to two AFT AND circuits. One output logic up-tuning instruction signal E.sub.U of the AFT circuit enables the up-tuning AFT AND circuit only in a certain sub-range below the desired frequency. The other output logic down-tuning instruction signal E.sub.D of the AFT circuit enables the other AFT AND circuit only in a certain sub-range above the desired frequency. Consequently, deliberate application of up-or-down-tuning pulses to the UP or DOWN terminals changes the count as desired, being only partially counteracted by the lower frequency, AFT-controlled pulses to the opposite counter terminal.

Digitally controlled tuner with automatic fine tuning

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.

Automatically tuned memory television channel selecting apparatus

In a channel selecting apparatus for a television receiver having a tuner with a voltage-controlled variable reactance device as its tuning element; digital codes representing or identifying respective channels are stored at respective addresses in a memory, and a digital-to-analog converter provides an analog control voltage for the variable reactance device in correspondence to each digital code selectively read out of the memory in a channel selecting mode of the apparatus. Further, in a programming mode of the apparatus, the changing digitally coded counts of a counter which is counting sweep pulses are applied to the digital-to-analog converter for similarly controlling the variable reactance device and selected counts of the counter, for example, those which result in the appearance on the receiver screen of pictures or test patterns broadcast by selected television stations or channels, are written at selected addresses in the memory as the channel identifying digital codes. Preferably, the digital-to-analog converter is constituted by a pulse-width modulator which produces a chain of pulses at a constant repetition rate with the widths of such pulses being varied in dependence on the absence of coincidence between a circulating digital code and the digitally coded count from the counter as established either by read out of a channel identifying digital code from the memory or by counting of the sweep pulses, and the output of the modulator is passed through a low-pass filter to provide the analog control voltage in dependence on the modulated pulse width.

Channel selecting apparatus for a television receiver with an electronic

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 which 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. A 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 within a pull-in range of an automatic fine tuning (AFT) circuit, the latter changes the digital code applied to the converter in the sense for removing such deviation and thereby achieving the correct tuned condition. Further, when the detected deviation is outside the pull-in range of the AFT circuit, sweeping changes are made in the digital code applied to the converter for cyclically varying the receiving frequency and thereby bringing the latter at least into the pull-in range of the AFT circuit. The modified digital code resulting from the operation of the AFT circuit and/or from the sweeping changes in such code is stored in the memory in place of the read out digital code resulting in such deviation.

Channel selecting apparatus

Remotely actuated power control apparatus having a control signal processing circuit which receives a remote control signal emitted from a remote transmitter and controls a power switch of an electronic instrument. The control apparatus includes a battery connected to the remote control signal processing circuit for supplying an operating voltage to the latter, and it also includes a power supply circuit connected to the electronic instrument substantially in parallel thereto, whereby an electronic power of the electronic instrument is controlled ON and OFF by the power switch.

Remote power control apparatus

A television signal detecting circuit is disclosed which has a first electric source, a second electric source (ground potential) different from the first electric source, a series circuit inserted between the first and second electric sources and consisting of a resistor and a condenser, a switching element connected in parallel with the condenser and adapted to become conductive and non-conductive in response to a synchronizing signal of the television signal, and a voltage detecting device connected to a junction point between the resistor and the condenser. The series circuit consisting of the resistor and the condenser prevents the voltage detecting device from becoming conductive when the television signal is absent and only noise is supplied, whereby the erroneous operation of responding to the noise as if it were the television signal can be prevented. The presence of the television signal is determined via coincidence, or lack of it, between the horizontal synchronizing signals of the incoming signal and locally generated pulses.

Television signal detecting circuit

A remote control system for selectively controlling plural functions of electric apparatus comprising a combination of an improved transmitter for generating a command signal of a single frequency which is transmitted intermittently for a plurality of intervals of time, the length of each of which is determined in response to selection of one of the plural functions, and a receiver for receiving the command signal and producing a control signal for controlling the selected function in response to the length of each of the intervals and to the number of the intervals of the received command signal.

Growing community of inventors

Yokohama, Japan

Hisao Okada