Abstract: A printhead/paperdrive mechanism wherein the essential parts of the printhead/paperdrive mechanism are assembled into a self-contained unit using a support formed of a single piece of material. The support has a base portion and end portions formed so as to project from opposite ends of the base portion for creating a mounting space. Corresponding guide means are formed in at least the facing sides of the end portions of the support. A platen/paperdrive roller comprising a shaft having a suitable platen/paperdrive material applied between opposite end portions thereof is mounted into the space using a first pair of said guide means and an elongated printing means having opposite end portions which project axially therefrom is mounted into said space by a second pair of said guide means.

Abstract: A cardiac amplifier system with several patient electrodes includes an amplifier with a capacitor coupled input and a switch for coupling different ones of the patient electrodes to the amplifier. A circuit including a time delay, a pair of sequentially operated controlled conduction devices and a resistive network shunts the amplifier input and charges the coupling capacitors in a controlled fashion when the selector switch is operated to prevent switching transients from being applied to the amplifier.

Abstract: An ultrasound wattmeter for measuring the magnitude of energy radiated by a therapeutic ultrasound applicator includes a sealed, oil-filled housing within which a float assembly is suspended. The float assembly includes an ultrasound reflective float as well as a coil and a vane supported by the float. The float assembly assumes a null position in the absence of ultrasonic radiation. A window in the housing permits the application of ultrasonic energy from the applicator to the float for urging the float assembly in one direction from the null position. A magnet mounted on the housing adjacent the coil urges the float assembly in the opposite direction in response to energization of the coil. A light source and a light responsive device are located adjacent the vane for providing a position signal corresponding to the position of the float assembly.

Abstract: An improved automatic defibrillator operable from an internal rechargable battery power source or from an A.C. line when the battery is discharged utilizes a high efficiency flyback type power supply for charging the energy storage capacitor. The capacitor charging power supply employs an isolated output thereby allowing the defibrillator electrodes to be switched between the storage capacitor and an electrocardiogram unit by the discharge relay and avoiding the need for a separate relay or isolating impedance to isolate the preamplifier of the electrocardiogram unit from the defibrillator circuit. Finally automatic circuitry is employed to control the battery power supply so that the number of watt seconds (Joules) of energy delivered by the defibrillator may be easily selected by a single selector switch, and the charging of the capacitor terminated when the energy necessary to deliver the amount of energy selected has been stored.

Abstract: A diathermy apparatus includes a power oscillator for developing signals which are coupled to a patient by a tuned reactive coupling circuit. The magnitude of the oscillator signal is detected in the oscillator output circuit, and a corresponding control signal is developed. A reference signal is supplied by an output level selection circuit. The load imposed by the patient and the output circuit upon the power oscillator, and thus the magnitude of the oscillator signal, are maintained substantially constant by a servo control circuit. A motor driven variable impedance in the reactive coupling circuit is operated in response to differences between the control and reference signals.