Abstract: An improved system for and method of precisely controlling the temperature at a predetermined location at a preselected temperature selected from a range of temperatures is described. The preferred system for carrying out the preferred method includes a mixing valve for separating a fluid stream into first and second component streams and adjustable in response to a first contol signal so as to control the amount of separation of first and second component streams. The preferred system also includes a heater for heating the first compponent stream in response to a second control signal, a first evaporator for cooling the second component stream and a conduit for combining the heated and cooled component streams so as to provide a mixed stream to the predetermined location. The first and second control signals are provided as a function of the preselected temperature, the temperature of the heated first component stream, the temperature of the mixed stream and the temperature at said predetermined location.

Abstract: An electrically damped oscillation motor having a stator component, a rotor component, a permanent magnet which provides a magnetic field across the annular gap transverse to the axis of rotation of the rotor and a drive winding for passing an electric current that interacts with the magnetic field to produce rotational deflection of the rotor. Both a tachometer winding and a compensation winding are provided in fixed relation to the drive winding, the compensation winding being located at a greater radial distance from the annular gap than the tachometer winding, and the tachometer and compensation windings being connected together in circuit so that the signal induced in the tachometer winding due to electric current flow in the drive winding is cancelled by a similar signal induced in the compensation winding, while the tachometer and compensation windings provide a net velocity signal that is used to modify the electric current flow in the drive winding to electrically damp rotational motion of the rotor.