A control circuit comprises two series-connected pairs of saturable reactors, the two pairs being connected in parallel between a supply line and a load. Between one pair of reactors are connected two back-to-back diodes, the center tap of which is connected to the common point of the other pair of reactors. The difference between the voltages across the reactor main windings causes feedback which increases the magnetization of the cores and reduces further the impedance of the low impedance win...

A feedback shift register for use in a system processing a data signal received from a memory such as a magnetic disc or magnetic drum or from, for example, a communication line so as to detect and correct any error which may present in the data signal. The feedback shift register comprises means for producing address information by making a first logical operation on the input data and the internal state of the shift register, a memory providing data determined by a second logical operation amo...

A system for recovering otherwise lost power from a compressor and prime mover utilizing a Rankine cycle. While heat recovery from prime movers has been done, much energy is wasted by compressors which convert all the driving power to heat which has not been recovered. Thus, this invention provides for power recovery from both the prime mover and the compressor. A working fluid is pre-heated utilizing waste heat from the prime mover and compressor, such as that in the cooling medium, oil cooler,...

An electrodynamic loudspeaker which comprises a diaphragm which cooperates with a magnet system by means of a moving coil which is connected to said diaphragm and an optical measuring system which comprises two elements--a light source and a detector. At least one of said elements is connected to a central portion of the magnet system and the detector supplies a voltage which substantially corresponds to the displacement of the diaphragm. The other element is connected to the diaphragm and the m...

A distributed feedback optical device using a single crystal boule prepared with periodic spatial striations of ternary Pb.sub.1-x Sn.sub.x Te and Yb impurity atoms forming a layered array of planar p-n junctions normal to the axis of light emission. Crystal surfaces parallel to the axis are coated with a reflective, electrical insulator. Free scattering losses are minimized by applying a magnetic field along the longitudinal axis.

This hands-free telephone prevents acoustic feedback between its speaker and microphone by attenuating either the transmission or receive path under the control of a corresponding pair of counters (computers), each counter sensing the signal divided and digitized from its corresponding path. An increase in counted pulses indicates feedback and causes a counter to more quickly reach a predetermined counter state (count), to trigger attenuation (damping) before it can be reset (restored) to zero b...

A sound reproduction system of the MFB-type (motional feedback), comprising an amplifier and a loud speaker system, the woofer of which is provided with a transducer producing in the lower frequency range a feedback signal proportional to the accelerations of the woofer membrane. The loudspeaker system is provided with a filter connected to the main signal input and designed so as to produce a reference signal in accordance with the expected ideal transfer function of the woofer and its associat...

An electrohydraulic servovalve having a pair of linear, variable, differential transducers (LVDT) affixed thereto in side by side relationship. A spool valve driven by the electrohydraulic servovalve is connected to the movable core in each of the LVDTs so that as the spool valve moves, each of the LVDTs develops a position output signal representative of the position of the spool. The connecting mechanism between the driven spool valve and the LVDT cores is a rod which is attached to the spool ...

To apply herbicide to weeds extending above a crop, a nylon carpet on the cylinder of a roller applicator has herbicide applied to it as a tractor or other vehicle carries it through a field. The roller is held just above the crop where it contacts weeds and is rotated in the opposite direction as the tractor. A moisture sensor is spaced from the applicator on the roller and controls a valve that applies the herbicide to the roller to maintain a preset moisture level in the roller carpet. The am...

Apparatus is presented for the precision control of an output signal in accordance with an input signal. The output signal is the output of a hydraulic motor, the output of which is compared to an electrical input signal in a geared differential comparator, the output of the comparator operating a distributor supplying the hydraulic motor.