摘要:
This invention discloses a monostable multivibrator which is useful for an FM detector circuit of a pulse count system. The monostable multivibrator has a time constant circuit which includes a capacitor, an amplifier circuit which receives an output of the time constant circuit, a positive feedback circuit which is connected between an output end of the amplifier circuit and an input end of the time constant circuit, and a trigger terminal which is disposed in a circuit loop constructed of the time constant circuit, the amplifier circuit and the positive feedback circuit; and is characterized in that the amplifier circuit is a differential amplifier which is made up of a pair of transistors connected in the differential form, the transistors being connected in common through emitter resistances connected in series with respective emitters thereof. Thus, the monostable multivibrator can provide pulse signals of a fixed pulse width without being influenced by noise.
摘要:
A first intermediate frequency amplifier stage which executes the amplitude limiting operation of a double-converting FM tuner employing the integrated circuit technology is constructed in the form of an integrated circuit. An output signal of the first intermediate frequency amplifier stage is put into a square pulse waveform on the basis of the amplitude limiting operation, and therefore has higher harmonic components of high frequencies. When the higher harmonic components are injected into a second mixer circuit in a second frequency converter circuit, various higher harmonic components which have frequencies higher than a second intermediate frequency appear at the output of the second mixer conduit. When the higher harmonic components at the output of the second mixer circuit are injected into an FM demodulator circuit, beat trouble is induced. The second frequency converter circuit is also constructed in the form of an integrated circuit, and filter means to pass the fundamental waves of a first intermediate frequency signal and to reject the higher harmonic frequency components thereof is connected between the output of the first intermediate frequency amlifier stage executing the amplitude limiting operation and the input of the second mixer circuit, whereby the beat trouble can be prevented.
摘要:
A monostable multivibrator circuit including a time constant circuit which includes a capacitor, an amplifier circuit which receives an output signal of the time constant circuit, and a positive feedback circuit which is connected between an output end of the amplifier circuit and an input end of the time constant circuit, characterized in that a trigger circuit is incorporated in a part of a circuit loop which is constructed of the time constant circuit, the amplifier circuit and the positive feedback circuit, the trigger circuit comprising an emitter-follower transistor which receives a feedback signal, another emitter-follower transistor which receives a trigger signal and whose emitter is connected to an emitter of the first-mentioned emitter-follower transistor in common, and a constant-current circuit which supplies a constant current to the emitters connected in common. Thus, the monostable multivibrator circuit can provide a predetermined pulse signal without any interference attributable to a trigger input circuit.
摘要:
This invention relates to a monostable multivibrator which is operated in the non-saturated state. The monostable multivibrator circuit includes a time constant circuit which has a capacitor, an amplifier circuit which receives an output signal of the time constant circuit, a positive feedback circuit which is connected between an output end of the amplifier circuit and an input end of the time constant circuit, and a trigger terminal which is disposed in a circuit loop constructed of the time constant circuit, the amplifier circuit and the positive feedback circuit; and it is characterized in that the positive feedback circuit comprises a signal amplifying transistor which has a base receiving an output of the amplifier circuit and a collector supplying a signal to the time constant circuit, and a level clamp circuit which is coupled to the collector of the transistor in order to hold a collector output potential of the transistor higher than a base input potential thereof.
摘要:
A trigger pulse forming circuit for converting a pulse signal into a trigger signal waveform is disclosed. It is characterized in that a time constant circuit is comprised in a collector output circuit of one of a pair of transistors for differential amplification and that a clamp circuit which employs a diode of the base-emitter path of a transistor is inserted between collector output circuits of the transistors for differential amplification. The input pulse signal to be subjected to the waveform conversion is impressed across the bases of the transistors for differential amplification, and the trigger pulse output signal is derived from the collector of the other of the transistors for differential amplification.
摘要:
A monostable multivibrator circuit is disclosed. It is characterized by comprising a time constant circuit which includes a capacitor, an amplifier circuit which receives an output signal of the time constant circuit and in which a signal amplifying transistor operates in the non-saturated state, a positive feedback circuit which is connected between the output end of the amplifier circuit and the input end of the time constant circuit and in which a signal amplifying transistor operates in the non-saturated state, and a trigger terminal which is disposed in a circuit loop constructed of the time constant circuit, the amplifier circuit and the positive feedback circuit. Further, it is characterized in that a signal which is produced by the shift from the non-conductive state to the conductive state of the signal amplifying transistor connected to an output terminal of the positive feedback circuit is supplied to the time constant circuit as a positive feedback signal.
摘要:
A metallic material containing both a second constituent and a third constituent having positive and negative heats of mixing relative to a first constituent, respectively, and including a compound, an alloy or a nonequilibrium alloy having a melting point that is higher than the solidifying point of a metal bath made of the first constituent is placed in the metal bath. The metal bath is controlled to a temperature lower than a minimum value of a liquidus temperature within a range of compositional variations in which the amount of the third constituent in the metallic material decreases down to a point where the metallic material becomes substantially the second constituent so that the third constituent is selectively dissolved into the metal bath.
摘要:
A method for preparing a phosphorothioate RNA based on the oxazaphospholidine method, wherein cyanoethoxymethyl group is used instead of tert-butyldimethylsilyl group as a protective group of 2′-hydroxyl group of RNA.
摘要:
An illuminating device includes a light guide plate; a light source that is located opposite at least two adjacent end faces of four end faces of the light guide plate; and a chassis that has an opening through which light emanating from a light emission surface of the light guide plate passes. At least one optical sheet that includes a corner portion with an interior angle of greater than 90 degrees in a position corresponding to a corner portion of the light guide plate that is sandwiched between the two end faces opposite the light source is disposed between the light emission surface of the light guide plate and the chassis.
摘要:
An oligo-aminosaccharide compound formed by binding 3 to 6 saccharides, such as 2,6-diamino-2,6-dideoxy-α-(1→4)-D-glucopyranose oligomers, or a salt thereof, which has high affinity to a double-stranded nucleic acid.