Abstract: A self-balancing D.C.-substitution R.F. power measuring system includes ft and second high gain differential operational amplifiers, a bolometer element, and a reference resistor element. The amplifiers and the two elements are connected in a current loop with one of the elements connected between the output terminals from the differential amplifiers and the other of the elements connected between center points of isolated dual power supplies associated with each of the amplifiers. The inputs to one amplifier are connected from an adjacent end of one of the elements and the far end of the other element, while the inputs to the second amplifier are connected to the far end of the one element and the adjacent end of the other element. Current flows out of one amplifier and into the other.

Abstract: A novel antenna is disclosed which provides inherent filtering action by ch the frequency response curve of the antenna can be shaped. In the preferred inventive embodiment, the antenna comprises at least one elongated receiving element, and preferably two such elements in the form of a dipole, both elements being constructed, at least in part, of an electrically resistive material. A detector, such as a diode detector, is directly coupled to the receiving elements. The resistance of the receiving element and the capacitances of the receiving element and the detector form a distributed parameter RC filter, the values of which parameters can be carefully controlled so as to provide the desired frequency response curve shaping. In the preferred inventive embodiment, a conductive strip is disposed along the length of and preferably to both sides of each receiving element, with a layer of dielectric material being sandwiched therebetween, whereby the filtering action is enhanced.

Abstract: A flux averaging sphere having an improved efficiency and a high averaging nd diffusing effectiveness over the visible and ultraviolet ranges. The interior surface of the sphere is coated with a white diffusing material which has a higher reflectance for visible radiation than for ultraviolet radiation. A radiation converting means is disposed inside the sphere for converting incoming ultraviolet radiation to visible radiation before reflections from the sphere wall occur. The radiation converting means is transparent to incoming visible radiation which therefore remains unaffected. The efficiency of the device is further improved by eliminating the small gap between the output area of the sphere and the face of the photomultiplier tube. The sphere is formed with a tapered tubular extension at the output area and the face of the photomultiplier tube is abutted against the end of the extension thereby forming a substantially light tight seal.

Abstract: This apparatus for monitoring the chlorine concentration of water has a uue internal calibration capability and a high sensitivity. A water sample is mixed with a solution of potassium iodide and the reaction produces a mole of iodine for every mole of chlorine present in the water. The mixture is passed through a detection and calibration assembly wherein the iodine is detected amperometrically by a detection cell. Calibrant (known) iodine fluxes, equivalent in effect to the unknown chlorine-produced iodine fluxes, are supplied to the detection cell during calibration runs by means of an upstream calibration cell which electrolyzes the iodide (preferably added to distilled water) to iodine at flux rates given simply by the electrolyzing currents divided by Faraday's constant. An electronics package having gain and offset controls and a concentration display is provided.

Abstract: A tunnel diode pulse generator is triggered through a directional coupler. he tunnel diode is coupled across one end of an output transmission line through an impedance matching network which matches the characteristic impedance of the transmission line. Triggering signals are coupled to the transmission line through the directional coupler for propagation of triggering impulses towards the tunnel diode.

Abstract: Apparatus for measuring the frequency of a reference signal which utilizes he color subcarrier signal of a television receiver as a standard frequency signal. In a first embodiment, the reference signal controls a circuit to develop bursts of a synthesized color subcarrier signal, gated at the horizontal line rate of a color television receiver. The synthesized signal is superimposed on the broadcast television signal and applied to the receiver to produce a modulation bar on the screen. Any frequency/phase difference between synthesized and broadcast color subcarrier signals will cause the modulation bar to move laterally across the screen, and/or cause the sequence of colors within the modulation bar to vary. Movement of the modulation bar is a coarse indication of frequency difference and change of the color sequence within the bar is a precise indication of phase difference.