Abstract: A carbon fiber production method includes a carbon fiber production step including an oxidation step and a carbonization step; and an exhaust gas processing step including a heat exchange step; an external air mixing step; and a mixed external air supplying step in which the mixed external air is supplied to at least one step that uses heated gas in the steps in the carbon fiber production step; and among the exhaust gases, a high heating value exhaust gas having a heating value of 250 kcal/Nm3 or higher is supplied to an inlet side of an exhaust gas combustion apparatus and a low heating value exhaust gas having a heating value lower than 150 kcal/Nm3 is supplied to an outlet side of the exhaust gas combustion apparatus, respectively.

Abstract: A carbon fiber production method includes a carbon fiber production step including an oxidation step and a carbonization step; and an exhaust gas processing step including a heat exchange step; an external air mixing step; and a mixed external air supplying step in which the mixed external air is supplied to at least one step that uses heated gas in the steps in the carbon fiber production step; and among the exhaust gases, a high heating value exhaust gas having a heating value of 250 kcal/Nm3 or higher is supplied to an inlet side of an exhaust gas combustion apparatus and a low heating value exhaust gas having a heating value lower than 150 kcal/Nm3 is supplied to an outlet side of the exhaust gas combustion apparatus, respectively.

Abstract: A variable frequency amplifier includes a main amplifier system 4 for amplifying one of signals into which an input signal is split by a directional coupler 3 to output the amplified signal, and an injection amplifier system 9 for adjusting at least one of the amplitude and phase of the other one of the signals into which the input signal is split by the directional coupler 3 according to a setting provided thereto from outside the variable frequency amplifier, and for amplifying the other signal and injecting this amplified signal into an output side of the main amplifier system 4.

Abstract: A variable frequency amplifier includes a main amplifier system 4 for amplifying one of signals into which an input signal is split by a directional coupler 3 to output the amplified signal, and an injection amplifier system 9 for adjusting at least one of the amplitude and phase of the other one of the signals into which the input signal is split by the directional coupler 3 according to a setting provided thereto from outside the variable frequency amplifier, and for amplifying the other signal and injecting this amplified signal into an output side of the main amplifier system 4.

Abstract: A high frequency amplifier includes a constant voltage driven amplifier 1 using as its amplifying element a bipolar transistor 7 with its base biased by a constant voltage, and a constant current driven amplifier 2 using as its amplifying element a bipolar transistor 8 with its base biased by a constant current. The idle current of the constant current driven amplifier 2 is set at a low value. In accordance with the idle current, the idle current of the constant voltage driven amplifier 1 is adjusted, and the two amplifiers are combined in parallel.

Abstract: A high frequency amplifier includes a constant voltage driven amplifier 1 using as its amplifying element a bipolar transistor 7 with its base biased by a constant voltage, and a constant current driven amplifier 2 using as its amplifying element a bipolar transistor 8 with its base biased by a constant current. The idle current of the constant current driven amplifier 2 is set at a low value. In accordance with the idle current, the idle current of the constant voltage driven amplifier 1 is adjusted, and the two amplifiers are combined in parallel.

Abstract: A holding frame includes a first surface, a second surface opposing the first surface, a plurality of inner sides, and a plurality of outer sides, for accommodating a display device within the plurality of inner sides. The holding frame includes at least one first protruding portion for receiving an external force applied to the display device. The at least one first protruding portion is provided on an inner edge which corresponds to one of the plurality of inner sides.

Abstract: An information reproducer which includes reading device for a reading visual information and sound information printed on a printing sheet, a storage device for storing the visual information and the sound information read by the reading device, a display device for selectively displaying the stored visual information on a screen, a visual information designating device for designating a partial area of the visual information displayed on the display screen, a connecting device for connecting the partial area of the visual information designated by the designating device with a part of the sound information corresponding thereto, and a sound information reproducing device for reading, from the storage device, and reproducing the sound information connected with the designated visual information.