Abstract: An apparatus and method are disclosed for testing connections between printed circuit boards and components mounted thereon. A conductive loop is formed by forward biasing a parasitic diode that is inherently present between an integrated circuit (IC) lead and the ground plane of the IC. A magnetic field is created by an antenna mounted above the component to be tested. When the antenna is energized by an RF source, a voltage is induced in the conductive loop if the loop is continuous, i.e., if all of the connections are properly made. The voltage in the loop is measured and compared to a selected threshold to produce a pass/fail indication. This tester may be implemented as an improvement to a standard type of "bed-of-nails" printed circuit board tester. The antenna may be implemented as an array of spiral loop antennas, with adjacent antennas producing magnetic fields that are 90 degrees out of phase with each other.

Abstract: A self-contained personal microwave and RF detector, which includes, inter alia, the housing and associated electronics of a standard hearing aid, is configured to produce an audible indication to a wearer thereof in response to electromagnetic fields of dangerously high levels within predetermined frequency ranges.

Abstract: A high-speed, highly sensitive microwave detection system and method, which uses the nonbolometric detection mechanism in a high-temperature superconducting thin film detector. A microwave signal is received by a broadband spiral antenna. The signal is modulated and optionally amplified before being transmitted to the superconducting detector through an impedance matching circuit. The superconducting detector generates an output voltage which is preamplified and then measured using a lock-in amplifier. A computer then records the measured output voltage.

Abstract: An RF inspection tool in for testing RF leakage of a slot radiator antenna array. The inspection tool comprises a vacuum chamber having a cover with a flexible metal diaphragm. The periphery of the cover seals to a base structure by means of an O-ring seal. The flexible diaphragm preferably comprises an aluminum sheet that conforms to the face of the antenna array when a vacuum is created within the tool. The flexible diaphragm has a plurality of flanges bonded thereto that allow access to and provide test points for the radiating slots of the antenna array. The flexible diaphragm is pulled toward the face of the antenna array when a vacuum is formed, and provides a tight seal against the face of the antenna array. The seal prevents RF leakage out of radiator slots of the antenna array. A network analyzer is used to transmit and receive RF energy through the flanges which are disposed adjacent different modules of the antenna array. Crosstalk or electrical leakage is measured using the network analyzer.

Abstract: Electromagnetic radiation monitor for use in close proximity with a human body. The monitor includes electromagnetic radiation sensors and shielding disposed behind the sensors which defines a radiation barrier between the monitor user and the sensors. A layer of uniform lossy material is disposed between the sensors and the shield for preventing reflective interference from the shield.

Abstract: A microstrip probe that can be inserted into the mouth or radiating portion of a thick flared notch or open ridged waveguide radiator element within an array antenna aperture and coupled to the TEM feed circuit transition of that element. The probe can then be used to extract performance diagnostic data of the circuitry behind the array aperture without removing the aperture itself. The probe bypasses the radiating portion of the array element and the effects of mutual coupling associated with the array. The probe is a printed circuit board whose thickness matches the gap dimension of the flared notch feed circuit transition line at its feed launch point. A coaxial connector at one end provides a connection to a microstrip line formed on the circuit board. The ground plane of the microstrip narrows to transform the microstrip line into a broadside coupled strip transmission line, which runs to the insertion end of the probe. The strips are shorted together at the insertion end.

Abstract: In order to measure radiation emitted from or the influence of radiation on an individual circuit board, which in use normally is arranged in a rack in parallel to other circuit boards, all circuit boards being connected to a common backplane, the backplane is modified in such a way that the connection of a considered board will be located on the opposite side of said backplane compared to the connections of the others boards. The whole equipment is located in a shielded housing except the considered circuit board. Thus the radiation from the other circuit boards will be shielded or attenuated and only the radiation from the considered circuit board will contribute to the radiation field around the device. In the same way only this considered circuit board will be sensitive to electromagnetic radiation arriving from the outside. The power supply of the device is preferably provided by power equipment located inside the shielded housing, such as a battery as well as a direct voltage power adaption unit.

Abstract: A combined signal level meter and leakage detector having a built-in antenna for the leakage detector, and dual clock frequency control of the microcontroller along with bandwidth switching for greater sensitivity in leakage detection mode. A data logging function is also provided. Control circuitry is also provided for avoiding receiver spurs by combined switching of multiple local oscillator frequencies, including combinations of high-side and low-side injection and IF shifting.

Abstract: A RF sensor for monitoring voltage, current and phase angle of a RF signal being coupled to a plasma reactor. Outputs from the sensor are used to calculate various properties of the plasma. These values are then utilized to characterize the process and/or used to provide feedback for in-situ control of an ongoing plasma process.

Abstract: An instrument which provides a measurement of the frequency and power of a microwave signal supplied to an input port of the instrument. The instrument includes: a resistive device which divides the microwave signal supplied into first and second microwave divisions thereof; a frequency counter which measures the frequency of the first microwave division, thereby providing the measurement of the frequency of the microwave signal supplied; and a power sensor and power meter combination which measures the power of the second microwave division. The power sensor and meter combination makes a calibration correction dependent on the frequency measured by the frequency counter to its power measurement, thereby providing the measurement of the power of the microwave signal supplied.

Abstract: A high frequency magnetic field exposure meter for use in an induction heat sealing operation for heat sealing metal foil elements in closures to containers to be closed by the closures. The meter has a magnetic field sensing coil, a rectifier to convert the a.c. output from the coil to a d.c. output, an integrating circuit to integrate the d.c. output over an exposure period to an h.f. magnetic field, and a display device to indicate the integrated exposure value generated by the integrating circuit. During operation, the meter generates a quantitative reading indicating exposure to the h.f. magnetic flux as an integral of the magnetic flux, which generates the induction heating currents, over the exposure period during the induction heat sealing operation, and the reading provides a useful measure of the induction heating generated in an induction heat sealable closure.

Abstract: An antenna (3) charged by a diode (4) is arranged at each of the points of a surface (30). The source (1) and a collecting antenna (5) are arranged on the same side of this surface, in the vicinity of each other. A layer (32) of absorbent material is provided, one face of which fits the shape of the surface (30) and is arranged on the side of said surface (30) opposite that of the source (1) and of the collecting antenna (5). An addressing circuit (33) of the diodes (4) which fits the shape of the other face of the absorbent layer (32) is connected, via connections which pass through said layer (32) perpendicular to the surface (30), to each of the diodes (4). The use of the modulated diffusion method permits the measurement of the near field radiated by a transmission antenna or diffracted by an object illuminated by a microwave radiation.

Abstract: The disclosure relates to the servo-control of an electronic circuit that calls for the detection of the power delivered at its output. The disclosed device is essentially constituted by a field-effect transistor with zero bias V.sub.DS mounted between the ground and a matching network at output of the circuit. This transistor behaves either like a capacitor or like a diode. A low-pass filter, connected between the transistor and the network, delivers a detection voltage V.sub.det.

Abstract: A wide power range radiation monitor includes a pair of diodes with their cathodes interconnected and with an additional capacitor coupled in parallel to one of the diodes. The detector, of the radiation monitor provides two outputs, a low power output and a high power output, which outputs are connected to the anodes of the detector diodes. The arrangement of dual diodes and capacitance provide the diode detector of the monitor with a greater than 40 dB square law region.

Abstract: An improved correlation method that computes E field measurements from voltage measurements produced by a TEM cell. Twelve voltage measurements are taken of radiation emanating from a device under test (DUT) for respective frequencies. The measurements are taken for the six faces of a hypothetical cube enclosing the DUT in both polarizations. Using these 12 measurements, the method identifies the face and polarization of the DUT which produces the highest emanation of radiation at that respective frequency. The method obtains three input voltages from these measurements and determines if the assumption of a dipole gain is adequate. If not, the actual gain is calculated and is used in a 3-input correlation algorithm to obtain more correct data regarding the E field emission of the DUT.

Abstract: A wide power range radiation monitor includes a pair of diodes with their cathodes interconnected and with an additional capacitor coupled in parallel to one of the diodes. The detector of the radiation monitor provides two outputs, a low power output and a high power output, which outputs are connected to the anodes of the detector diodes. The arrangement of dual diodes and capacitance provide the diode detector of the monitor with a greater than 40 dB square law region.

Abstract: An apparatus is disclosed which accurately measures, over a wide ambient temperature range, the average power derived from an electrical signal. Furthermore, embodiments of the present invention can be fabricated with inexpensive, off-the-shelf components and can have excellent circuit characteristics at RF frequencies. These results are obtained in an illustrative embodiment of the present invention that comprises a first thermal detector, a second thermal detector, an error amplifier and a summer. The first thermal detector provides a reference signal, which varies with the ambient temperature, to the error amplifier. The summer receives the signal to be measured and the signal output from the error amplifier, and outputs to the second thermal detector a composite signal, which is indicative of the sum of the power derived from input signal and the output signal from the error amplifier.

Abstract: A circuit tracer for determinating the location of a conductor, such as a wire, which is either an open or closed circuit, and which may lie underground. The tracer includes a transmitter which is connected to the conductor, a hand-held probe, and a receiver which is connected to the probe. The probe has three different sensors: an electric field sensor, primarily for locating the terminus of an open-ended conductor or for distinguishing such a wire in a bundled cable of wires; a differential electric field sensor, for determining the direction to and location of an open-ended conductor located above ground; and an inductive sensor for determining the direction to and location of a current-carrying conductor, including an open-ended conductor lying below ground. A switch selectively provides the output from one of the sensors to the receiver unit, which determines the magnitude of any signal based upon the direction the probe is pointing.

Abstract: Electrostatic discharge (ESD) sensing apparatus for testing and displaying extremely high frequency discharges. The apparatus incorporates a surface mounted current shunt in the form of a thin foil or film of less than one skin depth thickness at the frequency of interest. This is sandwiched between a coaxial connector base plate and a ground plane mounting plate. The foil or film is symmetrically oriented about the axis of the connector at a central opening in the mounting plate. A discharge path is provided through the opening to the foil and, on the other side, through a small resistor to the central conductor of the coaxial connector which may be connected to a measuring or display apparatus for a complete test system. A calibration unit includes a plurality of sensing devices configured for different cutoff frequencies and levels of discharge pulses.

Abstract: A monolithic integrated circuit power sensor provides a monolithic integrated circuit substrate, a conversion element formed either on or in the substrate for converting microwave energy into heat, and a thermally sensitive diode junction formed in sufficiently close proximity to the conversion element to be thermally coupled thereto.

Abstract: Radio-wave propagation is rapidly predicted by a hybrid computational method that uses Ray Optics techniques to calculate radio field strength above a limiting radio-wave ray, Parabolic Equation techniques to calculate radio field strength below the limiting radio-wave ray and below a predetermined altitude, and a newly created Extended Optics method to compute radio field strength in an area of the atmosphere below the limiting radio-wave ray and above the predetermined altitude. Rays in the extended optics area are initialized from the elevation angle that rays traced through the parabolic equation area make with the predetermined altitude. Where reflected, direct or origin created rays do not exist within the parabolic equation area, the elevation angle for the ray that does exist at the furthest range (optical limit) is used to initiate ray tracing in the extended optics area for ranges beyond the optical limit.

Abstract: Bidimensional electromagnetic emission level monitoring equipment for detecting the electric fields or the magnetic fields of RF (Radio Frequency) emissions from equipment under test by moving an electromagnetic probe bidimensionally. The measuring frequency, the scanning range of the probe, and the distance between measuring points are entered on a keyboard of a controller. A spectrum analyzer selectively receives RF emissions of a designated frequency from the probe in response to an instruction from the controller and feeds emission level signal data to the controller as digital signals. A probe scanning section loaded with the probe is moved bidimensionally by a motor driver under the control of the controller. The controller delivers to a display an emission level distribution signal representative of an electromagnetic distribution based on the emission level data and position data associated with the probe.

Abstract: A thermal power sensor for providing an output signal that is linearly related to the amount of power derived from a power source over a first range and that is square law related to the amount of power derived from a power source over a second range which may overlap the first range. The apparatus comprises a pair of matched transistors connected in a common emitter configuration. Each of the matched transistors is thermally coupled to a matched resistor so that heat generated in the resistor is transmitted to its respective transistor to cause temperature variations therein. The current through each transistor is a function of the temperature of the transistor. The matched transistors are connected in series with a pair of cascode transistors. The cascode transistors are connected to a first differential amplifier which senses and amplifies the differential voltage which results from any difference in current flow through the matched transistors.

Abstract: A wide power range radiation monitor includes a pair of diodes with their cathodes interconnected and with an additional capacitor coupled in parallel to one of the diodes. The detector of the radiation monitor provides two outputs, a low power output and a high power output, which outputs are connected to the anodes of the detector diodes. The arrangement of dual diodes and capacitance provide the diode detector of the monitor with a greater than 40 dB square law region.

Abstract: A field strength measuring instrument for simultaneously measuring E and H fields is described. A loop antenna is formed by a half-loop (1) which is terminated by a metal surface (2). Due to the mirror effect of the metal surface (2), this arrangement, in field theory, is equivalent to a loop antenna which is divided into a first and a second half-loop (1, 5) by two load resistors (4a, 4b) arranged at opposite ends of the loop antenna. A circuit (8) for determining the field strengths of the E and H fields by means of the voltages (V.sub.1, V.sub.2) measured across the load resistors (4a, 4b) is arranged in a part-space shielded from the first half-loop (1) by the metal surface (2).

Abstract: This application describes a novel method and its implementation for testing unpopulated and populated electronic printed circuit boards (PCBs). This method can be used to develop a new contactless test system (CTS). While eliminating drawbacks of existing test systems, this method measures electromagnetic near field distribution in the vicinity of a PCB, contactlessly, by using suitable sensors (possibly printed near field planar antennas) and sensitive measuring and processing devices. The electromagnetic fields (EMF) are generated by the distribution of charges and currents on paths and elements of the board under test (BUT). Therefore, accurate and repeatable measurements of these fields produce a specific pattern for the BUT. Such a pattern is then compared to a known pattern for the same type of board to determine whether the BUT is faulty or nonfaulty.

Abstract: The present invention concerns a circuit processes the power signal emitted from an RF power sensor (SK) of a radio telephone to create a detector voltage which is proportional to the power level of the radio telephone transmitter. The circuit comprises a transistor (Q2) acting as an active rectifier, which in the ascending part of the positive half cycle of the power signal charges a capacitor (C3). During the descending part of the power signal the capacitor starts to discharge with a time constant which is remarkably greater than the cycle length of the power signal. The transistor is biassed by means of a transistor (Q1) so that it is conductive even at the lowest power levels.

Abstract: A microwave power sensor is disclosed which is capable of using diodes above their resonant frequency to sense the power of input microwaves. The power sensor includes a sensing diode, a conditioning means, and a tapered waveguide. For input waves having frequencies near and above the resonant frequency of the sensing diode, the output of the diode begins to be frequency dependent. That is, the diode outputs different DC signals for waves having different frequencies even though the power of the waves is the same. The conditioning apparatus is adapted to offset the frequency dependence of the diode by varying the fraction of the input wave that is transmitted to the diode so as to cause the output of the diode to be relatively constant for waves having equal power but different frequencies. The conditioning apparatus also provides a load impedance which matches the characteristic impedance of the input wave to minimize the reflection of the input wave.

Abstract: A radio frequency ("RF") power sensor providing RF signal power sensing with reduced dependency upon its input signal power level includes multiple series-connected diodes for detecting the power of an input RF signal and providing an output voltage representing that power. The multiple series-connected diodes couple the input node shunted by an input load resistor to the output node shunted by an output filter capacitor. Using multiple series-connected diodes results in reduced reverse bias voltages across the diodes (presented by the charged output filter capacitor), thereby increasing their junction capacitances. These increased junction capacitances, in turn, result in reduced fractional changes thereof (e.g. capacitance "modulation") over changes in the input RF signal power. This reduction in fractional capacitance changes as a function of input signal power variations, further in turn, results in reduced input signal power dependency of the sensors' impedances and sensitivities.

Abstract: The invention describes an internal test load and method for forming an internal test load which is adapted to absorb energy from a power source such as an RF transmitter, transceiver, or amplifier. The test load is positioned internally within a housing, and includes at least one impedance device, such as a power resistor, coupled to the power source which is matched to the impedance thereof. The impedance device is supported on a heat sink which is adapted to absorb heat generated by the impedance device so as to be distributed over a relatively large area constituting the heat sink. The heat sink is positioned in spaced part relation to the housing, and is not directly supported or secured to the housing. A potting material surrounds the load assembly and supports the heat sink, wherein the heat sink effectively "floats" within the potting material such that heat absorbed by the heat sink will not be directly transferred to the housing, but will be dissipated through the potting compound.

Abstract: An antenna for sensing stray RF radiation, such as from electronic equipment, is positioned within a dielectric enclosure. For the case of a dipole sensing antenna, the enclosure may take the form of a clear acrylic (i.e., Plexiglas) tube. This tube assures that no part of the equipment-under-test can be positioned nearer to the dipole antenna than the desired distance (which is fixed by the radius of the tube). The dipole elements themselves may be maintained coaxially disposed within the tube by spacer disks. If the dipole elements are telescopic, their lengths can readily be set by attaching the spacer disks to the outer-most telescoping member of each element and moving the spacer disks (and in so doing moving the ends of the dipole elements) into alignment with markings disposed on the tube. These markings may be calibrated either in terms of distance or the corresponding resonant frequency.

Abstract: A fluxmeter pneumatically measures the amount of plasma energy impinging onto a semiconductor wafer. The fluxmeter is comprised of two hollow bulbs filled with gas. One bulb has one end exposed to the plasma while the opposite base end is supported by a substantially constant temperature wafer chuck. The other bulb has one end exposed to a heater and the opposite base end supported by the chuck. The two bulbs are coupled to a differential pressure sensor, which output is coupled to a servo for controlling the current to the heater. When plasma energy is applied, gas pressure in the first bulb changes and is sensed by the pressure sensor. The servo then adjusts the heater current until the gas pressure in the second bulb equals that of the first bulb. Upon reaching equilibrium the heater current is measured to determine the plasma energy flux impinging on the wafer.

Abstract: A radiation beam calorimetric power measurement system for measuring the average power of a beam such as a laser beam, including a calorimeter configured to operate over a wide range of coolant flow rates and being cooled by continuously flowing coolant for absorbing light from a laser beam to convert the laser beam energy into heat. The system further includes a flow meter for measuring the coolant flow in the calorimeter and a pair of thermistors for measuring the temperature difference between the coolant inputs and outputs to the calorimeter. The system also includes a microprocessor for processing the measured coolant flow rate and the measured temperature difference to determine the average power of the laser beam.

Abstract: A removable alternating current measuring circuit provides for measuring radio frequency currents produced in an AM transmitter-antenna system without draining any power from the system. A transformer couples the transmitter-antenna system with the current measuring circuit, which includes a first and second half wave circuits for operation during the positive and negative half cycles of alternating current. During the positive half cycle, a first diode directs current through a first load resistor and through a series combination including a second load resistor and a direct current meter. During the negative half cycle, a second diode in opposition to the first diode directs current through the second load resistor and through a series combination including the first load resistor and the current meter. Current always flows through the meter in the same direction.

Abstract: A wave-leakage measuring apparatus compares the power density of the leakage waves, in the portions on the upper side, the lower side, the left side, the right side of the high-frequency heating apparatus which is being measured in two steps, with the leakage locations by a central data processing computer to select one of the maximum wave-leakage locations. The apparatus then brings one of the power-density detectors to the maximum wave-leakage location by a robot and precisely measures the power density of the leakage waves while a wave-mode converting apparatus of the high-frequency heating apparatus which is being measured makes at least one rotation. The apparatus then automatically determines the acceptability of the measured values by the central data processing computer.

Abstract: An electromechanical XY carriage sweeps a magnetic or electrical field probe across a circuit board line by line to acquire field strength data as a function of probe position relative to the board. Colored field maps are produced. The carriage is controllable to obtain very high resolution data. A magnetic probe includes a single loop oriented parallel to the board or a loop oriented perpendicular to the board and selectively parallel to or perpendicular to the x axis of the carriage. Different field maps are produced by different probe orientations and each provides information regarding the circuit traces which carry rf currents.

Abstract: A microwave calorimeter is disclosed for substantially measuring the total icrowave energy in an applied microwave pulse. The microwave calorimeter includes: a housing having a highly reflective interior surface, a microwave absorbing device disposed in the housing for substantially absorbing microwave energy transmitted into the housing and for producing a thermal response proportional to the amount of microwave energy being absorbed, and a measurement device responsive to the thermal response for determining the amount of microwave energy being absorbed by the microwave absorbing device.

Abstract: Electromagnetic emission from a printed circuit board is monitored by energizing the board while it is located adjacent an array of electromagnetic emission measuring probes. The probes are successively addressed and currents induced in the probes are measured at a receiver. A memory map of the electromagnetic emission as a function of board position is generated and is displayed together with the circuit board layout so that regions of high emission level can be identified in the circuit. Each probe of the array is a series connected pair of wire loops, the planes of the loops being perpendicular to each other and to the plane of the array.

Abstract: The present invention relates to devices utilized for measurement of high frequency and microwave power. More specifically, the present invention relates to apparatus and technique for measurement of power including the construction and configuration of a power-sensing probe for detection of the power level of a high frequency or microwave signal.

Abstract: A device for measuring electromagnetic wave leakage from power supply lines and digital equipment by a system of focused concave reflective plates, an antenna to disburse and detect radiation, and an instrument to measure the leaked radiation.

Abstract: A temperature compensated power detector utilizes a temperature compensating diode connected to an inverting input of an amplifier to enable the amplifier to substantially cancel out undesirable temperature effects caused by a power level detector diode coupled to the non-inverting input of the amplifier. As a result, the amplifier output voltage tends to remain constant over temperature in response to a fixed power level being applied to the detector. A lookup table is utilized to determine the power level corresponding to a power detector output voltage of a particular magnitude.

Abstract: In an arrangement for measuring the energy of a microwave pulse a container (2) is placed on the end of a waveguide (1). In container (2) there is an absorption liquid (3) with a given heat content, which absorbs the energy of the irradiated microwave pulse. The increase of the heat content thus caused which corresponds to the energy of the microwave pulse is determined by the volume expansion of the absorption liquid (3). For this purpose container (2) is connected to a capillary (4). Preferably container (2) is covered with a reflection layer (12). Further, it is additionally connected to a balancing volume (5) and is cooled with a cooling coil (14).

Abstract: An improved RF shielding integrity monitoring system is provided for monitoring the shielding integrity of a shielded enclosure that accurately identifies degraded shielding effectiveness and leakage areas in the shielded enclosure. The RF shielding integrity monitoring system performs self-testing and self-diagnostic routines to assure proper system operation prior to monitoring of the shielded enclosure. The RF shielding integrity monitoring system includes a transmitter for transmitting predetermined transmitted by the shielded enclosure for receiving the signals; a receiver separated from the transmitted predetermined signals and for identifying the shielding effectiveness of the shielded enclosure; and a cable connected to the transmitter and the receiver for communicating signals between the transmitter and the reciever.

Abstract: A wide dynamic range radio-frequency power sensor having a low-power sensor portion and a high-power sensor portion is described. Both sensing portions are connected to an input signal at the same time without the use of a signal splitter. In the preferred embodiment, a single radio-frequency load serves both sensor portions. Each sensor portion has its own output terminal. The low-power sensor portion includes a pair of diodes. The high-power sensor portion (which includes the radio-frequency load) may include a pair of diodes preceded by an attenuator, or a pair of thermocouples.

Abstract: A microwave oven wattage detector having a visually and microwave transparent container holding a thermally homogeneous fluid having a wattage-indicating strip contained in the fluid with a plurality of different temperature-sensitive areas on the strip with indicia associated with each of the areas to indicate power levels when such container is heated within a microwave oven for a set time and one of such temperature-sensitive areas changes color to denote the indicia indicating the power level of the microwave oven.

Abstract: A current detector for detecting the high frequency current flowing in a conductor includes a coil of high resistivity material wound around an non-ferromagnetic core. The coil is arranged in a substantially closed loop configuration around the conductor carrying the current to be measured. The ratio of the winding spacing to the cross sectional area of the coil is maintained constant over the length of the winding. A shield of high resistivity material surrounds the coil and is spaced from the coils and the shield has a gap oriented along an azimuth of the closed loop winding and directed orthogonal to the net current direction of the current induced in the coil. The ends of the coil are coupled to a high impedance voltage detector through high resistivity leads and a relatively low value resistor is coupled between the leads to reduce the quality factor.

Abstract: A probe for sensing radio frequency power, utilizing two independently-driven radio frequency-sensitive diodes. The two diodes are driven through a common RF input, through a branch network which separates and feeds the probe RF power to each diode independently. The diodes are unequally padded from the RF input, to provide an extended sensitivity range for the probe. One diode, therefore, operates in a lower dBm range, while the other diode operates in a higher dBm range. Two separate outputs are provided from the probe to supply a common power meter which monitors the appropriate output for the present power level of the radio frequency input.

Abstract: A mechanical probe for optical measurement of electrical signals. The probe for optical measurement of electrical signals with high chronological resolution is composed of a cuboid electro-optical crystal, of a co-planar waveguide structure located on a lateral face of the crystal and of a metallic tip applied to the end face of the crystal adjacent a measuring location. The signal at the measuring location, for example at an interconnect of an integrated circuit is taken with the metallic tip and is fed into the co-planar waveguide structure composed of two strip-shaped metallizations. Probe holders or electrostrictive manipulators known in the art of electrical metrology (probe measuring location) can be used for exact positioning of the probe onto the measuring location.

Abstract: The invention concerns an apparatus and technique for detecting the voltage of A.C. high voltage lines. A radar wave is transmitted towards the high voltage lines and is reflected to a detector when the AC voltage drops to threshold level. Reflection continues until the AC voltage cycles to the threshold level on it second half of the cycle. A time interval is calculated for radar reflection and non-reflection, and a ratio thereof is calculated by a microprocessor which generates a display indicating the voltage carried by the AC lines in accordance with the time interval ratio.

Abstract: A threat field sensor has a hollow metal enclosure with imperforate side walls except for a single aperture that is small as compared with the wavelength of interfering electromagnetic energy. A coaxial conductor is located in the enclosure cavity and has separate sets of leads interconnected to each conductor end. Electric signals induced in the coaxial conductor and present at the conductor ends by the external electromagnetic fields passing through the enclosure aperture are converted to two corresponding light signals. The light signals are transmitted to remotely located processing apparatus by an optical fiber link where the light signals are converted once again to electric signal counterparts. Summing and differencing these electric signals provides two final signals representative of the electric and magnetic field, respectively.