On a circumferential side surface of a single cylindrical member constituting a main body of a rotor section are disposed, in parallel, a first pattern which repeats change in the circumferential direction with a predetermined pitch and a second pattern which has a change of one cycle with respect to one circumference. A detection head section which is provided in proximity to the rotor section changes its relation of correspondence to the respective patterns in accordance with rotational position of the rotor section and produces output signals corresponding to the relation of correspondence. A relatively rough absolute value of a rotational position within one rotation is established by an output signal produced in response to the second pattern and its accuracy is established with a high resolution by an output signal produced in response to the first pattern. By disposing the first and second patterns in parallel on the single cylindrical member of the rotor section, the construction of the device can be simplified.

A linear synchro/resolver comprised of an opposed pair of stator assemblies, each of which has a plurality of corresponding, opposed, toothed pole piece pairs, a toothed slider movably mounted between the opposed sets of pole piece pairs, and wherein the pole piece pairs on each stator assembly are spaced apart along the assembly's length by a non-integral multiple of the pitch of the stator teeth. Separate coils are wound on the stator pole pieces, with the coils of adjacent and opposed pairs of coils being connected together in phases. The inductance of the coils is thus a function of the alignment of the slide teeth with the stator pole piece teeth. A source of alternating current is connected to the phases of coils, the current magnitude flowing through each phase of the coils is detected, and the current magnitude differences between the phases are amplified. The phases of each of these amplified current differences are then compared with the phase of the source signal to produce an output signal which is representative of the position of the slider relative to the pole pieces.

A monolithic transformer compensated circuit with enhanced quality factor without significantly increasing noise levels is presented in this disclosure. The technique uses a monolithic transformer and a current source driving current into the transformer secondary winding to achieve loss compensation in the transformer primary. An ac current which is proportional to, and in phase with the voltage applied to the primary winding can be used to achieve theoretically perfect loss compensation at a given frequency in the RF (GHz) frequency range. Examples of circuit applications that are particularly suited to the technique include Voltage Controlled Oscillators (VCO's), Low Noise Amplifiers (LNA's) and Filters. The technique has the added advantage of reducing power consumption in some applications.

The invention concerns an inductive transmitter comprising two coils (1, 2), each with one core (3, 4). The two cores (3, 4) are capable of being moved relative to each other. Two systems are integrated in the transmitter that make it possible to simultaneously transmit data and/or energy, as well as the position of the two cores (3, 4) relative to each other. Finally, the transmission of data and/or energy takes place by means of induction, and the determination of the position of the two cores (3, 4) relative to each other takes place via a measurement of the magnetic field that exists between the two coils (1, 2).

In a magnetic detector for receiving a reference position signal in movement from an encoder track and a reference track arranged on a member included in a magnetic position sensor, magnetic pickups respectively confronting to the encoder track and the reference track are provided and both tracks jointly yield a position reference signal.