Abstract: An FM signal demodulator has a phase shifter including transversal filters for producing from a FM video signal two FM video signals which are different in phase by 90.degree. from each other, and a demodulator for detecting phase information of the FM video signal, wherein the carrier frequency is at least quadrupled prior to demodulation so as to suppress components of the FM video signal not to be included in the demodulated video signal.

Abstract: A magnetic reproducing apparatus which has a pair of main rotatable heads having different azimuth angles and a pair of auxiliary rotatable heads having different azimuth angles. When a magnetic tape is played back while it runs at a speed different from that at which it runs during a recording mode, playback output signals from the main and auxiliary rotatable heads are switched over to replace a reduction in the outputs from the main rotatable heads with the outputs from the auxiliary rotatable heads to produce a combined playback output signal. The combined playback output signal is passed through a variable delay line having a delay time varied by an output from a detector circuit which detects variations in horizontal synchronous signal intervals of the combined playback output signal.

Abstract: An apparatus for measuring a weight including a tuning fork vibrator to produce an oscillation signal having a frequency determined in accordance with a weight applied to the vibrator, a circuit for detecting an abnormal increase in an amplitude of the oscillation signal due to disturbing vibration to produce an abnormal signal, a frequency counter for counting the number of waves of the oscillation signal except for a period during which the abnormal signal is generated and a data processor for resetting the frequency counter each time the frequency counter has counted waves of the oscillation signal for a predetermined period and calculating a measured weight from a count value of the frequency counter.

Abstract: A video tape recorder has a simple helical-scan construction capable of variable-speed reproduction free from noise bars on reproduced images at desired speeds ranging from a normal speed in reverse reproduction to threefold normal speed in forward reproduction.

Abstract: A video signal processing apparatus has an input terminal for receiving an input video signal and a delay line for delaying the input video signal. A first transmission circuit processes the video signal which has been delayed by the delay line and a first timer reversal circuit reverses the time sequence of the input video signal during a predetermined time period. A second transmission circuit processes the time reversed signal from the first time reversal circuit and a second time reversal circuit reverses the time sequence of the signal processed by the second transmission circuit. An adder circuit adds the signal processed by the first transmission circuit and the time reversed signal from the second time reversed circuit. A control pulse generator produces a control pulse sequence which inverts its level every predetermined period so as to control the first and second time reversal circuits. The output of the adder circuit serves as the output signal processing apparatus.

Abstract: In a video tape recorder of the helical scan type, two auxiliary magnetic heads having different azimuth angles are provided in the vicinity of two main magnetic heads. The main and auxiliary magnetic heads have their tracks aligned so as to compensate for the reduced period of the reproduction signal of the main magnetic heads during high speed reproduction by using the reproduction signals of the auxiliary magnetic heads. Thus, blur free high speed reproduction pictures may be realized, and, at the same time, a dancing picture correction during still reproduction may be facilitated.

Abstract: A tracking-error correcting system in a rotary head magnetic recording and reproducing apparatus in which reproducing magnetic heads are mounted on a respective bimorph leaf having piezoelectric elements so as to be movable in the direction of the axis of rotation. The piezoelectric elements are controlled by a control voltage which is produced by adding a signal from an auto-tracking circuit and a signal from a triangular wave generating circuit. In a reproducing mode at a tape speed which is different from a tape speed in recording mode, this system activates the auto-tracking circuit when the control voltage level is within a limited range which is detected by a control voltage detector. Also, this system stops the auto-tracking circuit during a transition period when the reproduction mode changes.

Abstract: A mechanism for converting a weight into a frequency by means of a tuning fork vibrator having a pair of elongated plate-like vibrating strips extending in parallel with each other, a lever unit with a power pivot, fulcrum pivot and a load pivot, and a base portion, both ends of the tuning fork vibrator being coupled with the power pivot of the lever unit and the base portion, respectively by means of thin plate-like members. The weight to be converted is applied to the load pivot of the lever unit and is transferred to the tuning fork vibrator by means of the lever unit. All the parts of the mechanism are formed integrally from a single plate.

Abstract: A video signal recording/reproducing apparatus includes a first set of rotary heads mounted on a rotary disk and a second set of rotary heads mounted on head actuators which are also mounted on the rotary disk. The apparatus has two reproduction modes. A magnetic tape in the first reproduction mode is driven at a speed equal to the speed used in a recording mode. The magnetic tape in the second reproduction mode is driven at a speed which is different from the speed used in the recording mode. The apparatus has a negative feedback loop which detects the reproduced signal level of the second set of rotary heads and drives the head actuators in order to increase the reproduced signal level of the second set of rotary heads. In the first reproduction mode, the negative feedback loop is intermittently closed.

Abstract: A video signal recording/reproducing apparatus has two main rotary heads, two sub-rotary heads, and a recorded video tape. One main rotary head M1 has a +6.degree. azimuth angle and one sub-rotary head S1 has a -6.degree. azimuth angle. The sub-rotary head S1 is mounted near the main rotary head M1. For example, the distance between the main rotary head M1 and the sub-rotary head S1 corresponds to two horizontal sync signal intervals of a video signal. Main rotary head M2 has a -6.degree. azimuth angle and sub-rotary head S2 has a +6.degree. azimuth angle. The distance between the main rotary head M2 and the sub-rotary head S2 is the same as that between M1 and S1. The main rotary head M2 is located at a position opposite to the main rotary head M1 on a rotary head disk. In the fast motion reproduction mode, the main rotary head M1 and the sub-rotary head S1 scan recorded video tracks on the video tape. The reproduced signal of the main rotary head M1 has several lower or zero level positions in one field.

Abstract: A positionable element driving circuit for driving a positionable element compensates the supplied voltage-position characteristics of a bimorph type piezoelectric element which is used in a track following type video tape recorder/reproducer and which displaces the position of a video head. The supplied voltage to the bimorph type piezoelectric element is generated by an operational circuit which detects the track position of the video head. The circuit of the present invention compensates for the non-linearity and maintains the track following when the video tape recorder/reproducer is switched from one mode to another, e.g. from a still motion mode to a quick motion mode.

Abstract: A recording time mode detector for automatically detecting the recording time mode of reproducing video tape. This detector is constructed of a counter which counts the number of rotations of the capstan which drives the reproducing video tape and is reset by a reproduced control signal. The recording time mode is detected by the count stored in the counter.

Abstract: A tracking system of the present invention comprises positionable elements, rotary video heads mounted on the positionable elements, a control head, a frequency generator attached to a capstan motor, and a displacing pattern generator. The displacing pattern generator includes counters which count the pulses from the frequency generator and are reset by control signals reproduced by the control head, a still pattern generator, and an adding means which adds the output signal from the counter and the output signal from the still pattern generator. The output signal of the displacing pattern generator is amplified and applied to the positionable elements. As result, the video heads mounted on the positionable elements can properly trace on a recorded video track at both a normal tape speed or at another tape speed.

Abstract: A tracking system including positionable elements, rotary video heads mounted on the positionable elements, a control head, a frequency generator attached to a capstan motor, and a displacing pattern generator. The displacing pattern generator includes counters which count the pulses from the frequency generator. The pattern generator is reset by control signals reproduced by the control head, a still pattern generator, and an adding means which adds the output signal from the counters and the output signal from the still pattern generator. The output signal of the displacing pattern generator is amplified and applied to the positionable element. As result, the video head mounted on the positionable element can properly trace on a recorded video track at a normal tape speed or at a different tape speed.

Abstract: A video tape recorder performs tracking by moving its video heads vertically with respect to the scanning direction of the video tracks through the use of an electric-mechanical transducer. The video tape recorder measures the cycles of the synchronizing signals included in the reproduced video signals, so that the electric-mechanical transducer shifts the video heads to enable regular measuring, thereby allowing the video heads to scan on the regular video tracks.

Abstract: A recording and reproducing apparatus for color video signals, in which before the color video signal is recorded, the chroma signal of the color video signal is frequency-converted by a carrier from an oscillator whose frequency is f.sub.a =[(455/2)+{(2n+1)/4}]f.sub.H so that the chroma signal is compressed to a very low frequency band with the sidebands of the chroma signal being interleaved with each other. The thus compressed signal is frequency-modulated and recorded, and is then reproduced and demodulated. The demodulated signal is balance-modulated and passed through a comb-filter to reproduce the chroma signal. Since the chroma signal is frequency-modulated before the recording, possible fluctuation of the signal level due to the recording and reproducing means does not affect the resulting reproduced chroma signal. Also, since the chroma signal is compressed to a very low frequency band, a time base error (jitters) which might possibly occur in the resulting reproduced chroma signal due e.g.

Abstract: A VIR-signal processing circuitry for a VTR (video tape recorder) having a comb filter for obtaining a correct operation of the VIR circuit incorporated in a television receivers, comprises a comb filter stopping means for preventing the VITS (vertical interval test signal) on the 18th line from polluting the VIRS (vertical interval reference signal), a phase transfer means for transferring the phase information of the transmitted VIRS to the reference subcarrier after elimination of the crosstalks by integrating the VIRS, an amplitude transfer means for transferring the amplitude information of the transmitted VIRS to the output signal of said phase transfer means after elimination of the crosstalks by integrating the VIRS, and a VIRS replacing means for replacing the transmitted VIRS by the newly developed chrominance reference using the output signal of said amplitude transfer means.

Abstract: This invention relates to a high power bipolar transistor comprising a collector region, a base region formed in the collector region and emitter regions formed in the base region, with each of the emitter regions being a closed loop at the surface of the base region. The emitter electrode contact region is arranged at the surface of base region and surrounded by the emitter region, and the emitter electrode contact region and emitter region are connected by a conductive area, with the conductive area being shallower than the emitter region. In addition, the conductive area is connected to the internal surface of the emitter region at one or more points but is not connected to the entire part of the internal surface of the emitter region.

Abstract: A transistor which has a plurality of ring emitter transistor units formed on a common semiconductor substrate having one conductivity type, each ring emitter transistor unit being provided with a base region of the opposite conductivity type from the semiconductor substrate and formed on its surface, an emitter region of the same conductivity type as the semiconductor substrate and formed in the base region to a depth smaller than the latter to have a ring-shaped plane configuration, a base electrode formed in the vicinity of the outer or inner periphery of the ring-shaped emitter region, an emitter electrode formed in the vicinity of the inner or outer periphery of the emitter region, and a ballasting resistor formed to interconnect the emitter region and the emitter electrode. The product of the area of the emitter region and the resistance value of the ballasting resistor is selected to be in the range of from 6.0 .times. 10.sup.-4 to 1.3 .times. 10.sup.-3 [.OMEGA..multidot.cm.sup.