Abstract: A receiver has a tuner for receiving a TV broadcast program and a modem for receiving an e-mail. Also, the receiver outputs a message if there exists any unopened e-mail. In addition, the receiver has a camera for sending a videophone image. A viewer in front of the receiver is recognized, and it is determined whether or not the recognized viewer matches the addressee of the unopened e-mail. If a result of the determination is negative, a message output operation is prohibited.

Abstract: The first unlock code is composed of a number “m” of characters, all of which belong to a predetermined category. The second unlock code is composed of a number other than the number “m” of characters, or composed of characters at least one of which does not belong to the predetermined category.

Abstract: An electronic device is provided with a first lock release code store memory including a first lock release code; a lock release flag store memory including a lock release flag that shows whether or not a lock is released; a comparison portion comparing the first lock release code with a second lock release code input by an input device; a control portion releasing, when the comparison by the comparison portion results in agreement, the lock to permit the electronic device to operate normally; and a determination portion determining whether or not the lock release flag store memory is authentic.

Abstract: An electronic device includes a memory storing a first lock release code, a comparing portion comparing the first lock release code with a second lock release code that is input with an input device, a controlling portion permitting the electronic device to operate normally if the comparing portion finds that the first lock release code matches the second lock release code, and a restricting portion restricting an acceptance of an input of the second lock release code after input attempts have been made a predetermined number of times if the comparing portion finds that the first lock release code does not match the second lock release code.

Abstract: An electronic device includes a first rewritable nonvolatile memory storing a first lock release code, a comparing portion comparing the first lock release code with a second lock release code that is input with an input device, a controlling portion permitting the electronic device to operate normally if the comparing portion finds that the first lock release code matches the second lock release code, and a first error checking portion checking whether or not there is an error in the first lock release code stored in the first rewritable nonvolatile memory. If the first error checking portion finds an error in the first lock release code stored in the first rewritable nonvolatile memory, the controlling portion permits the electronic device to operate normally regardless of a comparison result obtained by the comparing portion.

Abstract: Each of channel searching means comprises means for judging, when a search for the subsequent channel is started, whether or not receivable channel information or information indicating that receiving is impossible is stored in a channel map with respect to the subsequent channel, means for starting the search for the subsequent channel when the receivable channel information or the information indicating that receiving is impossible is not stored in the channel map with respect to the subsequent channel, and means for terminating the channel search when the receivable channel information or the information indicating that receiving is impossible is stored in the channel map with respect to the subsequent channel.

Abstract: A PLL circuit compares a PCR with the output frequency of a voltage controlled oscillator (VCO), and returns a voltage value which is the result of the comparison to the VCO, so that a reference clock corresponding to the PCR is outputted from the VCO. A switch supplies a control voltage from the PLL circuit to the VCO when digital broadcasting is viewed, while feeding a fixed voltage from a fixed voltage power supply to the VCO when analog broadcasting is viewed, to stably output a clock having a frequency of 27 MHz irrespective of the change in the PCR.

Abstract: A receiving section for digital television broadcasting and a receiving section for analog television broadcasting are provided. When a digital television broadcasting program is selected, it is judged whether or not an analog television broadcasting program having the same contents as those of the selected digital television broadcasting program is being broadcast. In a case where the analog television broadcasting program having the same contents as those of the selected digital television broadcasting program is being broadcast, when the digital television broadcasting program cannot be received, the analog television broadcasting program having the same contents as those of the selected digital television broadcasting program is received and outputted.

Abstract: A receiver has a tuner for receiving a TV broadcast program and a modem for receiving an e-mail. Also, the receiver outputs a message if there exists any unopened e-mail. In addition, the receiver has a camera for sending a videophone image. A viewer in front of the receiver is recognized, and it is determined whether or not the recognized viewer matches the addressee of the unopened e-mail. If a result of the determination is negative, a message output operation is prohibited.

Abstract: There are provided an analog tuner for receiving analog broadcasting and a digital tuner for receiving digital broadcasting. An EPG decoder extracts EPG data in analog broadcasting, and a demultiplexer extracts EPG data in digital broadcasting. A CPU receives each of the EPG data, to judge whether or not the same program is being broadcast in analog broadcasting and digital broadcasting (whether or not there is simulcast). The CPU produces, when analog broadcasting in simulcast is being received, a message that the same program is being broadcast in digital broadcasting by an OSD circuit and displays the produced message on a screen (a CRT).

Abstract: Each of channel searching means comprises means for judging, when a search for the subsequent channel is started, whether or not receivable channel information or information indicating that receiving is impossible is stored in a channel map with respect to the subsequent channel, means for starting the search for the subsequent channel when the receivable channel information or the information indicating that receiving is impossible is not stored in the channel map with respect to the subsequent channel, and means for terminating the channel search when the receivable channel information or the information indicating that receiving is impossible is stored in the channel map with respect to the subsequent channel.

Abstract: There are provided first channel searching means for sequentially tuning in to broadcasting channels using an analog broadcasting receiving unit, judging whether or not analog broadcasting is receivable for each of the broadcasting channels, and storing receivable channel information related to analog broadcasting in a channel map with respect to the broadcasting channel on which analog broadcasting is judged to be receivable, and second channel searching means for sequentially tuning in to the broadcasting channels excluding the broadcasting channel on which analog broadcasting is judged to be receivable by the first channel searching means using a digital broadcasting receiving unit, judging whether or not digital broadcasting is receivable for each of the broadcasting channels, and storing receivable channel information related to digital broadcasting in the channel map with respect to the broadcasting channel on which digital broadcasting is judged to be receivable.

Abstract: A PLL circuit compares a PCR with the output frequency of a voltage controlled oscillator (VCO), and returns a voltage value which is the result of the comparison to the VCO, so that a reference clock corresponding to the PCR is outputted from the VCO. A switch supplies a control voltage from the PLL circuit to the VCO when digital broadcasting is viewed, while feeding a fixed voltage from a fixed voltage power supply to the VCO when analog broadcasting is viewed, to stably output a clock having a frequency of 27 MHz irrespective of the change in the PCR.

Abstract: A fine color video signal including a fine component in a high frequency area has a level of an upper side band of the fine component raised by a predetermined level after FM modulation. An amplitude of the FM modulated color video signal is limited by a limiter amplifier, and as a result, levels of both the side bands become the same as an intermediate level between both the side band levels before limitation of the amplitude. Such an FM modulated color video signal is optically recorded on a video disc. In reproducing, a video disc player limits an amplitude of the reproduced FM color video signal after removal of the high frequency component thereof. Thus, both the side bands of the fine component become the same as a level of half the lower side band level before limitation of amplitude. Such an FM modulated color video signal is FM demodulated to be a fine color video signal.

Abstract: A peak holding circuit comprises a capacitor for holding signal charges corresponding to a peak level of an input signal, and a current amplifier circuit comprising transistors connected in a triple darlington manner for supplying an output current corresponding to the held charges. An emitter of a transistor in the first stage out of the transistors connected in a darlington manner is connected to a collector of another transistor through which a collector cut-off current flows which is approximately equal to a collector cut-off current flowing through the transistor in the first stage. The other transistor has its emitter connected to ground. Therefore, the collector cut-off current flowing through the transistor in the first stage is cancelled, so that fluctuations in output current can be prevented even if a large reactive current is not allowed to flow through a transistor in the final stage out of the transistors connected in a darlington manner.