Abstract: A miniature, ingestible and encapsulated telemeter device for transmitting information relating to deep-body temperature of a subject comprising a battery source of power, and a free running multivibrator circuit having fixed biasing means connected to oscillator having a predetermind resonant frequency. A thermistor having a negative temperature coefficient of resistance is connected to the battery and the fixed biasing means and is operative to vary the output frequency of the multivibrator circuit in proportion to the temperature of the thermistor, the oscillator being pulsed into alernate states of conduction and non-conduction at the output frequency of the multivibrator to produce an output consisting of bursts of energy at the predetermined resonant frequency, preferably in the range 88 - 108 MHz.

Abstract: The invention comprises of a pair of readout ring electrodes which are used in conjunction with apparatus for measuring the electrical impedance between different points in the body of a living animal to determine the amount of blood flow therebetween. The readout electrodes have independently adjustable diameters to permit attachment around different parts of the body between which it is desired to measure electric impedance. The axial spacing between the electrodes is adjusted by a pair of rods which have a first pair of ends fixedly attached to one electrode and a second pair of ends slidably attached to the other electrode. Indicia are provided on the outer surface of the ring electrodes and on the surface of the rods to permit measurement of the circumference and spacing between the ring electrodes. The ring electrodes are electrically isolated from each other.

Abstract: A non-dispersive gas analyzing apparatus is described having a first chamber for containing a first gas, the density of which it is desired to determine. A source of radiant energy is provided for passing radiant energy through the first chamber. Modulation means are provided for modulating the radiant energy passing through the first chamber by modulating the volume of the chamber at the acoustic resonance frequency of the first gas and the chamber. Signal generating means including a second chamber for containing a gas which is heated by radiant energy emerging from the first chamber and a microphonic means responsive to the resulting pressurization in the second chamber is provided for generating a signal having a frequency and amplitude corresponding to the modulation of the radiant energy in the first chamber.