An apparatus or unit for use with a number of tensiometers, for example, which may be located in different areas of a field to sense the moisture content of the soil in the area where each tensiometer is located. Each tensiometer is connected in series with a load, such as, a solenoid of a valve located in an irrigation line or a pump. The unit includes reed switches connected in series with the tensiometers and which are intermittently closed by the movement of a permanent magnet into close pro...

A cutter monitor is used to sense the position of a cutter. Optical non-contact means sense the position of the cutter and produce an electrical output that represents that position. The electrical outout is fed through electronic circuits that convert it to two signals. The first signal drives a directly readable digital output and the second signal is fed to a data processor.

A perfusion monitor for monitoring blood flow in a body. A transducer, associated with a part of the body, generates signals representing pulse wave forms. The signals are fed to a circuit which generates output signals corresponding to pulse rate and the area under the pulse curve. These latter signals are then multiplied and the result integrated. A signal proportional to the integrated result is then fed to a perfusion index meter which displays a reading of the blood flow.

A portable monitor for determining the electrical conductivity of a continuously flowing stream such as a liquid hydrocarbon treated with an antistatic material. The monitor utilizes a conductivity cell containing opposed planar electrodes while the associated power supply and amplifier are enclosed within an explosion proof case. The construction of the cell is such that a precise value for the cell constant is determined. The interelectrode separation is adjustable permitting various cell cons...

A cardiac monitor provides a real time analysis of critical cardiac functions. The cardiac monitor includes a first unit which, via a plurality of electrodes, is utilized to sense atrial and ventricular activity of a patient's heart to provide an analog EKG signal which includes the P,Q,R,S and T components of the analog EKG signal. The analog EKG signal is converted to a voltage controlled frequency modulated signal which is transmitted, via an FM transmitter, to a remote second unit which is a...

A respiration monitor for measuring the variations of the thorax impedance of a patient due to respiration activity includes circuitry for suppressing the indication of unwanted signals caused by the activity of the heart. This circuitry is connected to receive separate signals corresponding to the heart beat rate and compare the periods of these signals to those of the signals measured at the thorax of the monitored person. If the periods of both signals are substantially equal, i.e. the signal...

An apparatus for automatically monitoring the respiration of a subject requiring no physical connection to the subject. The use of such apparatus for automatically triggering an x-ray machine at instants of respiration extrema is also disclosed.

A method for monitoring the optical development of non-silver free radical film in which the fog buildup in a selected non-image portion of the film is used to control the intensity and/or duration of the development exposure so as to insure a desired level of contrast between image and non-image areas in the developed film.

A pressure monitor for an enclosed body possessing an internal pressure differential utilizing a chamber having a piston disposed for travel therewithin. The piston includes a transversely mounted electrical conductor which forms an electrical bridge with a pair of contacts disposed on either side of the piston. A monitor means electrically connects between the pair of contacts to indicate the internal pressure of the enclosed body.

A monitor camera device (10) has a camera housing (12) and a dehumidification regulation body (14). The dehumidification regulation body (14) has a dehumidification element (42), an electrode, and an engaging portion engaging with an engaged portion of the camera housing (12). One end side of the electrode is constructed so as to supply a power source to the dehumidification element (42), and the other end side penetrates through the engaging portion of the dehumidification regulation body (14)....