Abstract: A method and apparatus for testing the proper operation of the optical elements in the optical detection circuit of an electronic register in an energy meter. The light emitter circuit is periodically pulsed adequately to turn the emitters to the on condition, and a comparison circuit is provided in which the voltage across a monitor point in circuit with the light emitters and a switching circuit is monitored both before and after each pulse. The absence of a voltage change upon pulsing the light emitter circuitry is used to generate a first error or failure signal. The light detector is read prior to each pulse to determine if unprogrammed light is being received prior to the pulsing of the light emitter as an indication of tampering with the accurate reading of the energy meter, and a second error signal is generated in response to unprogrammed light.

Abstract: A production circuit tuning tool consisting of a cover and a number of feed-through, gold-tipped probes that adjust the performance of an underlying circuit. The probes are positioned in the cover so that they may act as temporary jumpers between the trace wiring and tuning patches on the circuit substrate. The portion of the probe that bridges the patches comprises a slender nonconductive plunger of low dielectric constant material having a gold plated tip. Once the proper combination of jumpers is determined, the tuning tool cover is removed, permanent jumpers are soldered into place and a regular production cover is installed.

Abstract: A method and apparatus for adjustment of the assembly of an electric power meter which rotates in response to power consumption which enables successive test positions to temporarily support the assembly without marking the bearing, and provides only a single mark on the bearing at the final factory adjustment position with an indication on the bearing of any subsequent tampering with that position.

Abstract: A performance board for mounting thereon an IC under test is attached to an analog testing part of an IC tester which includes first and second AC signal generators, a DC voltage generator, a timing signal generator, a digitizer, a precision voltage measurement unit and a test processor. On the performance board there are provided an analog switch, a detector circuit, a band pass filter connected to the output of the second AC signal generator, a band elimination filter connected to the output of the first AC signal generator and a switching circuit. The analog switch outputs a rectangular-wave signal by turning ON and OFF the output DC voltage of the DC voltage operator at the frequency and with the duty ratio of a timing signal from the timing generator.

Abstract: A unitary combination actuator and indicator flag for an electronic energy meter. The integral actuator and mode indicator is slidable within the bezel of the meter and in the off position is not visible. Sliding the actuator simultaneously moves a camming surface over an axially moveable switch to connect the meter test mode, and slides a visible "TEST" flag over the digital readout window to indicate that the watthour meter is in the test mode. Positive actuation and positioning members are included for both the off and on positions.

Abstract: An electronic watthour meter for metering the consumption of electrical energy on power lines includes phase compensation means for compensating for leading and lagging phase differences between line current and voltage, whereby sampling times of the current and voltage are shifted to compensate for phase errors between the current and voltage by controlling timing signals provided to current and voltage analog to digital converters. Digital output signals from the analog to digital converters proportional to current and voltage are multiplied to provide an accurate representation of energy consumption as a result of the compensation.

Abstract: A calibrator supplying electric parameters (viz voltage, current and resistances) over plural ranges to a meter to be calibrated comprises internal components for deriving each parameter over the plural ranges, an internal voltage reference, a DAC, a memory, an analog comparator and analog-to-digital converter. The internal components are connected in circuit with the internal voltage reference, analog-to-digital converter, comparator and memory for writing data signals into the memory indicative of calibration correction factors for the internal components. The internal components are connected in circuit with the memory and DAC so the DAC responds to the stored data signals indicative of the calibration correction factors to enable the value of the parameter supplied to the device by the internal components to be modified and corrected in accordance with the calibration correction for the parameter.

Abstract: A utility meter including an electronic module to calculate predetermined parameters related to electric utility line and load conditions. Signals related to utility line voltage and load conditions are scaled and sampled to generated a data base which is utilized by a digital processor to calculate the parameters discussed above. Calibration processes controlled by the processor corrects for errors related to the sensors used to sense line voltage and load conditions as well as drift in the analog portions of the electronic module.

Abstract: Apparatus for effecting field calibration of a portion of an electrical energy metering system, the system including a magneto-optic metering transducer (2,30) for producing an optical output signal representative of the current or voltage component of energy to be metered, and the portion of the system which is to be calibrated including a circuit unit (16,50) for receiving, when the metering system is in operation, the output signal produced by the metering transducer and a signal representative of the other component of the energy to be metered, and for generating an output signal representative of the energy delivered by the current and voltage components.

Abstract: A calibration circuit for a solid state electricity meter comprises a plurality of resistors formed on an integrated circuit. The resistors are connected by an on-chip array of electrically controlled switches, such as MOSFETs, to signal processing circuitry driving the meter. The resistors establish variable voltage divider networks which compensate the meter for phase, gain and offset errors distributed in the signal processing circuitry. The values of the variable voltage divider network may be established automatically during testing of the meter, by a digital computer, or semi-automatically, by a technician, to establish the "on" and "off" states of the various transistors of the array.

Abstract: An instrument to determine, under actual field conditions, which type of VA demand meters are most appropriate for a particular consumer. The type of electrical load that the consumer places on an electrical supply system can introduce harmonics and phase distortion in the system resulting in VA meters producing incorrect readings. These VA meters are intended to measure the true apparent power S which is defined as S=V.sub.rms XI.sub.rms but, are generally designed to operate according to one of the following approximate formula:(1) S'=V.sub.rect XI.sub.rect X(1.11).sup.2 and(2) S"=.sqroot.P.sup.2 +Q.sup.2 where P is the active power and Q the reactive power.The instrument contains circuit to measure the rms values of the voltage and current waveforms from which the true apparent power S can be obtained as well as circuits to determine the value S' and S" according to the two approximate formula from which error signals e.sub.1 and e.sub.

Abstract: Calibrating errors of a variable gain amplifier used in an AC calibrator or a meter for measuring AC are determined for a gamut of frequencies. The gain of the variable gain amplifier is varied by adjusting the value of a variable resistor in discrete steps. A variable amplitude signal is applied to the amplifier while the resistor is adjusted in discrete steps so the amplifier derives a gamut of variable amplitude signals that are supposed to have predetermined values. The amplitudes of the gamut of variable amplitude signals derived by the amplifier are detected and compared with the values that the signals are supposed to have to derive a calibrating error signal of the amplifier for each variable resistor value. A gamut of variable frequency, constant amplitude signals is applied to the amplifier while the amplifier gain is constant. The amplifier has a tendency to derive an AC output signal having a different amplitude in response to different ones of the frequencies.

Abstract: A diagnostic meter base, used for testing the connections of a self-contained meter in a polyphase installation is described. The diagnostic meter base comprises a box-like casing, one end of which defines a socket with contacts to engage respective contacts of the meter, and the other end of which defines a plug with contacts to engage respective contacts of a permanent support socket of the installation. The casing houses a network of circuit elements each including a lamp which responds to current through the element, whereby the pattern of lamp responses is indicative of the pattern connections in the installation. The lamp bulbs are mounted in a well at one end of the casing, the well having a hinged cover.

Abstract: The invention provides an improved pulse initiator circuit for attaching to utility meters to generate a pulse signal having a predetermined relationship to the rate of power usage measured by the utility meter. Electronic circuitry is utilized which automatically compensates for differences in individual utility meters permitting the pulse initiator to be used with any standard utility meter without calibration or adjustemnt. The pulse initiator is attached to the utility meter without breaking the meter seal.

Abstract: An electronic demand register includes a microprocessor including a program clock for performing timekeeping functions for the register. A power supply connected across the AC voltage source provides power to the microprocessor through a voltage regulator. The program clock is maintained by the line frequency of the AC source. Electronic circuits are provided for calibrating the program clock to be compatible with either a 50 Hz or a 60 Hz line frequency. A detection signal corresponding to the line frequency is generated by a line frequency detector circuit in the power supply. A reference signal is generated by a quartz crystal clock. A frequency comparator circuit includes a microprocessor program that measures the time period between detection signal pulses. This time period is compared to the known period of a 50 Hz or a 60 Hz signal and respective counters are incremented accordingly.

Abstract: To prevent the driver from being confused by the fact that a pseudo vehicle speed to diagnose a vehicle speed meter is indicated when a vehicle speed sensor is disconnected by an accident during vehicle travelling, a pseudo vehicle speed sensor signal is applied to the vehicle speed meter only when the vehicle speed sensor is disconnected from the vehicle speed meter and the disconnected sensor is reconnected to the meter a predetermined time period after the sensor has been disconnected from the meter. The self-diagnostic apparatus is composed of counters, flip-flops and logical gates, and is reset whenever an ignition switch is turned on.

Abstract: Calibrating errors of a variable gain amplifier used in an AC calibrator or a meter for measuring AC is determined for a gamut of frequencies. The gain of the variable gain amplifier is varied by adjusting the value of a variable resistor in discrete steps. A variable amplitude signal is applied to the amplifier while the resistor is adjusted in discrete steps so the amplifier derives a gamut of variable amplitude signals that are supposed to have predetermined values. The amplitudes of the gamut of variable amplitude signals derived by the amplifier are detected and compared with the values that the signals are supposed to have to derive a calibrating error signal of the amplifier for each variable resistor value. A gamut of variable frequency, constant amplitude signals is applied to the amplifier while the amplifier gain is constant. The amplifier has a tendency to derive an AC output signal having a different amplitude in response to different ones of the frequencies.

Abstract: A device for non-destructive surface photovoltage testing of silicon-on-sapphire (SOS) wafers employs the electrically equivalent of an inserted capacitance in series in a measuring circuit. A pair of thin irridescent coated (TIC) glasses, are positioned on each side of an SOS wafer with an electrical lead attached to each of the conductive coating of tin oxide and indium tin oxide of the TIC glasses. The glass surface (the non-conductive side) of each TIC glass is positioned adjacent to the sapphire layer and silicon layer respectively. An incident light illuminates the sapphire layer and subsequently illuminates the silicon-sapphire interface with a predetermined wave length of light wherein the silicon absorbs all of the light within about 100A of the silicon-sapphire interface. Thus, the incident light is transmitted through the conductive layer of the first TIC glass which is in electrical contact with a detection circuit.

Abstract: A precision transmission line in the form of a short air line, and calibration of a network analyzer using the short air line, are disclosed. The short air line is approximately one-quarter wavelength at the middle frequency of the measurement frequency range. One embodiment comprises a very short coaxial air line. The inner conductor is threaded onto a mating inner conductor, such as the inner conductor of the network analyzer test port. For reliable interface at the other end of the inner conductor, a precision coaxial connector is preferably provided for connection to a device under test. The outer conductor is then attached coaxially to the inner conductor between the network analyzer test port and the device under test. Another embodiment comprises a waveguide for calibrations at higher measurment frequencies. In the case of the waveguide, locating structure is provided for properly orienting the waveguide with respect to the network analyzer test port and the device under test.

Abstract: A solid-state watthour meter for registering AC electrical energy consumption by a load connected to a source of AC load current and AC line voltage includes a voltage sensing transducer for producing a signal corresponding to the line voltage and a current sensing transducer for producing a signal corresponding to the load current. A solid-state measurement circuit receives the voltage and current signals as its inputs and produces an output signal corresponding to the AC electrical energy consumption of the load. A power supply, including a regulator circuit having a calibration resistor, provides a DC voltage to the measurement circuit. The DC voltage across the regulator circuit is dependent on the impedance of the calibration resistor. The measurement circuit includes apparatus for relating the registration of the meter to the DC supply voltage. The calibration resistor is readily removably electrically connected in the regulator circuit.

Abstract: An solid-state electricity meter includes an electronic measuring unit with an analog/digital converter which receives signals from amplifiers for various measurement ranges, and a control section with a microcomputer wherein the meter signal is processed, taking into account correction factors for the various elements of the circuit. Each correction factor is a single value for each respective measurement range, and the correction factors for each range are contained in corresponding meter-characteristic quantities which are stored in the electricity meter. Each meter-characteristic quantity represents a measurement value corresponding to a specific quantity of energy. Only a few (e.g., only 4) meter-characteristic quantities need be stored in the electricity meter. These meter-characteristic quantitites can be determined in a conventional calibration procedure, and they enable all the fixed errors of the signal processing to be compensated.

Abstract: A method and apparatus is disclosed for measuring flowing gas and at least one variable for calculating gas flow corrected to a base value of that variable. Illustratively, the measured variables are temperature and pressure, and devices are employed for measuring the temperature T.sub.f and pressure P.sub.f of the gas flowing through a conduit, and means in the illustrative form of a flow meter for measuring the volume V.sub.f of the gas flowing through the conduit. Calculating means in the illustrative form of a programmed microprocessor is employed to calculate the corrected gas volume to base conditions in accordance with an expression including the supercompressibility factor. The supercompressibility factor is calculated according to an equation involving only whole number exponentiation and a selected set of coefficients. The calculation means selects a particular set of these coefficients in accordance with indications of pressure and/or temperature.

Abstract: In an analog test system for testing integrated circuit chips, AC level calibration is achieved by adding a minimal number of new elements and more fully utilizing elements existing in the system. A reference voltage from an existing precision DC power source is fed to an analog switching device. A control signal is also fed into the analog switching device from an existing digital signal generator. Based on the control signal, the analog switching device converts the reference voltage into a rectangular waveform signal, which is then digitized. The digital signal is analyzed, and data from the digital signal is compared with reference data, and the AC level error, if any, is determined. AC level calibration is based on this error.

Abstract: A current-comparator technique for obtaining a load loss standard with adjustable loss tangent (or power factor) for in-situ calibration of transformer loss measuring system is described. The load loss standard, driven by the test voltage through a low-loss high-voltage compressed-gas-dielectric reference capacitor, simulates an inductive load which can be operated with load currents of up to 1000 A. For a 500 kV reference capacitor and a load current of 1000 A, the load loss standard simulates an equivalent inductive load with a rating of 500 MVA. Adjustment of the loss tangent (or power factor) is achieved by comparing the load current, using the current comparator, with in-phase and quadrature reference currents derived from the test voltage.

Abstract: Power from an alternating signal having a frequency variable in a wide and relatively high range such as approximately 10 megahertz to 40 gigahertz is indicated by a detector. To calibrate the detector, an alternating signal is introduced from a source to a bridge including a regulating member such as a thermistor. The bridge also receives a direct voltage. The thermistor is maintained at a particular impedance such as 400 ohms, regardless of the power provided by the alternating signal, by varying the magnitude of the direct voltage. The alternating signal, which is regulated in accordance with the dc voltage, is also introduced to the detector. The detector output is introduced to a data processing unit which processes the detector output to indicate the power from the alternating signal. The output from the data processing unit is converted to an analog signal which is combined with the signal from the bridge to produce a resultant signal.

Abstract: Measurement accuracy of an oscilloscope is extended by monitoring the temperature within the oscilloscope, and automatically entering a calibration cycle if the temperature varies by a predetermined amount. A temperature sensor is strategically located within the oscilloscope to sense variations in temperature. A first sensed temperature value is stored. Upper and lower temperature limits representing the maximum permissible deviation from the stored value are calculated. Instantaneous temperature values from the sensor are compared with the stored value, and as long as the instaneous values are with the limits, an indication of extended accuracy is provided. If the instantaneous temperature values vary outside the limits, an automatic calibration cycle is initiated. After calibration, a new temperature value is stored and the monitoring process continues to ensure extended accuracy.

Abstract: A system for calibrating an energy meter is provided. The energy meter has a rotor which rotates at an angular velocity generally proportional to the energy input to the meter. A reference transducer receives an energy input for generating a reference signal having a predetermined parameter, such as frequency, generally proportional to the energy input. A test apparatus is responsive to rotation of the rotor to generate a test signal having a predetermined parameter, such as frequency, generally proportional to the angular velocity of the rotor. An error signal generator receives the reference signal and the test signal upon fractional rotation of the rotor and generates an error signal to indicate the amount of error between the frequency of the test signal and a calibration value corresponding to the frequency of the reference signal. The meter is calibrated based on the error signal. A related method is also disclosed for calibrating the meter.

Abstract: A method and apparatus for automatically calibrating the deflection of an electron beam in a graticuled cathode ray tube. The apparatus includes a microprocessor and digital-to-analog converter for generating input signals of a predetermined accuracy and sending the signals to an amplifier of a cathode ray tube to deflect the electron beam across graticule lines on the faceplate. A phototransistor optically coupled to the faceplate detects the electron beam coinciding with the graticule and in response generates an electrical signal. Signal processing circuitry processes the signal to remove noise from it and retrieve detection signals. The microprocessor receives the detection signals from the signal processing circuitry, compares each detection signal to its corresponding input signal, and adjusts the gain and offset of the amplifier in response to the comparison. Additional circuitry digitally records the beam position relative to the graticule lines.

Abstract: A calibrated automatic test system includes a test station for generating digital test function codes and a test head containing a plurality of I/O pins for connection to a device under test. Each I/O pin includes a pin electronics circuit responsive to the digital test function codes for providing test signals to the device under test. The pin electronics circuits are inexpensive CMOS IC's and lack the accuracy needed to test VLSI devices at the frequencies of interest. An external calibration unit is connected to each I/O pin and data measurements are taken which represent the performance of the CMOS IC's. The data measurements are converted to calibrated function codes representing desired data values which are then stored in correction memory circuits which respond to nominal digital test function codes and substitute in their places calibrated function codes which are then supplied to the pin electronics circuits.

Abstract: A circuit for indicating when recalibration of an electrical sensor is necessary includes an analog driving circuit adapted to be coupled to the sensor, and an analog indicating device coupled to the analog driving circuit for indicating when the sensor should be recalibrated. The analog driving circuit provides a signal proportional to the current received from the electrical circuit. The indicating device is responsive to the output from the analog driving circuit and provides an output which is a function of both the sensor output and the elapsed time that the sensor has been operated.

Abstract: The electrical measuring meter comprises a polarized motor magnet mounted for movement to and from a starting position, a polarized holding magnet operative magnetically to influence the motor magnet constantly towards such starting position, and a calibrating element magnetized by the holding magnet to effect a partial cancellation of the holding magnet's influence on the motor magnet as is needed for calibration. The calibrating element preferably is in the form of a soft iron circular disc, and soft iron discs of different sizes are used to calibrate the meter for respective different maximum scale current values. Also, the high magnetic permeability of the soft iron disc enables the use of a rugged and economical sleeve bearing mount for the motor magnet even in a meter calibrated for low current measurement.

Abstract: An electronic calibrator having a CMOS integrated circuit transmission gate which responds to the output of a multi-vibrator. The output from the transmission gate is buffered and amplified to derive either a constant voltage or a constant current signal for delivery to a signal path.

Abstract: In a phase measurement apparatus having a phase detector for receiving a first frequency signal from a variable frequency signal generator and a second frequency signal from the generator through a calibration member having good linear frequency vs. phase characteristics and for detecting the input signals and outputting a phase difference signal, the apparatus further includes a first phase ratio operation section for changing an output frequency of the generator, receiving phase difference signals at frequencies as integer multiples of a phase difference of 2, and calculating a first frequency vs. phase difference ratio for the calibration member a second phase ratio operation section for changing the output frequency of the generator in a relatively narrow frequency range, receiving phase difference signals at upper and lower limit frequencies of the frequency range, and calculating a second frequency vs. phase difference ratio and a calibration section for comparing the first and second frequencies vs.

Abstract: A method of adjusting and testing for proper operation a current sensor by applying a threshold current value to the current sensor and adjusting the current sensor to a point just past the threshold of operation. Proper operation of the current sensor is tested by applying a non-operate current value followed by an operate current value to the sensor and checking for respective non-operate and operate output signals from the sensor. Messages, pass/fail indication, and audio signals are provided to signal test results to an operator.

Abstract: An apparatus for testing current sensors employing an electromagnetic coil and one or more Hall Effect switches including a microprocessor controlling a constant current source and visual and audio indicating circuits. A parameter input circuit is provided to permit an operator to select device types and to select test only, or adjustment and test sequences to be executed. The constant current source is adapted to apply a threshold, must-not-operate, and a must-operate current values to the electromagnetic coil. The visual and audio indicating circuits are adapted to provide messages, pass/fail indications, and audio signals signaling test success or failure results to an operator.

Abstract: A wire detector for semi-automatic wire stripper which responds to capacitance changes caused by sensing a capacitive object such as an exposed wire end and includes signal processing through an oscillator and amplifier circuit providing timer control for activating a relay driver circuit for an adjustable duration time period. The wire touch sensor circuit relay driver is then coupled through a mercury wetted relay which provides electrical isolation from external (switched) voltages to an air solenoid which, when actuated, allows the pneumatic mechanism of the wire stripper to cycle through its functions of wire stripping.

Abstract: A small field probe is calibrated by selectively varying the field intens and frequency and recording the data in arrays with each incremental step. The arrays are built by selectively varying one parameter while maintaining another constant. In this way coefficients of the equation for the calibration of the probe is arrived.

Abstract: An apparatus and method for verifying the accuracy of watt-hour meters at their operational site includes applying a phantom load to the meter and to a watt transducer. The relative watt hour readings of the meter are compared to the watt hours computed from the power to the watt transducer and represented as a percentage error of the meter. The phantom load is constituted by a loading transformer with optional load adjustments to take into account different loads to the meter and there are also adjustment means to take into consideration different meter characteristics. The meter watt hour reading is determined from an articulated light generating and receiving means mounted in alignment with the revolving disc so that light passes through the aperture in the disc to the receiving means and then signals the verifying apparatus to give an indication of the watt hour reading of the meter. Alternatively the reading is obtained manually.

Abstract: A measured signal is supplied to an indication section through a high-frequency amplifier, a frequency converter, and an intermediate frequency amplifier. A predetermined local oscillation signal from a local oscillator is supplied to the frequency converter. A reference signal generator generates harmonic pulses having a uniform level at a spectral interval substantially equal to or larger than the predetermined passband of the intermediate frequency amplifier, the uniform level being used to calibrate a level of the signal to be measured. A frequency setting section sets the frequency of the measured signal. A first switching section switches an input to the high-frequency amplifier to an output side of the reference signal generator in accordance with the frequency set by the frequency setting section.

Abstract: The present invention accepts accurately generated pulses, having a frequency of K pulses per second, from a suitable source of such pulses, and uses those pulses to phase correct the operation of a phase lock loop voltage controlled oscillator, which is designed to run at a frequency of N times K pulses per second. The output pulses from the voltage controlled oscillator are passed along a bifurcated path. Along one leg of said bifurcated path, the pulses are directed to a counter where they are divided down to provide an output signal at the rate of NK/P pulses per second and in the preferred embodiment, P equals N. The pulses from the counter are fed at the NK/P rate back to a phase comparator which provides an error voltage at the voltage controlled oscillator for each pulse.

Abstract: An electronic demand register performs rolling demand metering in which a demand interval is divided into N subintervals. At the end of each subinterval, the demand data from the just-completed subinterval is summed with the demand in the most-recent N-1 contiguous subintervals to derive an interval demand. A test operation is provided in which the stored maximum demand, a number representing the remainder of the subinterval interrupted by the test and programmed constants are stored in non-volatile memory but are also retained in the processor for use during test. A test reset switch resets accumulated demand data and presets the subinterval timer to predetermined values from which they may be operated by a calibrated test load to confirm the performance of the demand register. At the end of testing, all data in the processor is zeroed and the data stored in non-volatile memory is restored.

Abstract: An improved circuit is provided for a solid state electrical energy meter having a pair of mutual inductance current transducers, a pulse width modulation circuit, an analog switch, and a voltage-to-frequency converter. The pulse width modulation circuit includes an integrator having a first operational amplifier with a feedback circuit providing a constant DC gain and a variable gain at the power frequency. The pulse width modulation circuit also includes a second operational amplifier configured as a comparator and connected to the first operational amplifier such that the reference level of the comparator is proportional to the average DC output of the first operational amplifier. The summing resistors connected to the input of the integrator are of like value and are formed in a common array.

Abstract: A method for testing the correct position of a wiper of an electric potentiometer and an electric potentiometer for performing the method are proposed. The electric potentiometer includes a wiper lever with brush wipers, which upon a rotational movement about a pivot shaft brush over two work sections of an electrically conductive layer applied to a carrier plate. One of the work sections communicates on one side with a connection layer and on the other with a grounded connection layer, which the other work section communicates with a pickup connection layer. Respective testing faces are provided in the extension of the permissible movement paths of the brush wipers on the work sections, these testing faces being embodied as electrically non-conductive and in a testing position of the wiper lever being crossed by the wiper lever.

Abstract: An oscilloscope vertical calibration system is provided in which gain control elements in one or more vertical input channels are automatically controlled with respect to cursor voltages applied to the vertical output amplifier. Such calibration process is performed for each deflection factor setting either manually or automatically and the correct gain control signals are stored in memory.

Abstract: In an electron beam lithography apparatus a capacitance height gauge is used to determine the distance between a reticule and electron optics. In order to calibrate the capacitance gauge an optical interferometer, including a mirror are mounted on the same axis as the capacitance gauge. The mirror is moved a predetermined distance so that the movement distance measured by the capacitance gauge and the interferometer can be compared.

Abstract: A method and an apparatus for rating a thermometer probe, wherein the thermometer probe includes a small thermistor sensing element and a pair of conductors connected with the thermistor contacts and being supported upon a substrate. With the thermistor held at a particular temperature, the electrical resistance of the thermometer probe is measured and the difference between the resistance of that probe and a standard resistance is fed to a computer which operates a laser to encode a machine-readable character on the probe representative of the difference between the measured resistance of the probe and the standard resistance. In use, the probe is inserted in a readout and the readout senses the actual resistance of the thermometer probe which is dependent upon the temperature of the thermistor.

Abstract: A precision circuit for measuring electrical currents, of the order of only a few pico-amperes, in the individual ionic channels of biological membranes, comprising a pipette engaging a membrane and having an internal electrode connected to a current-to-voltage converter; the converter output is integrated and fed back to a reference potential source for the converter to control that reference potential so that the average pipette electrode is maintained at zero over a predetermined time interval. In the preferred construction the time constant of the feedback integrator is adjustable between a "slow" value and a "fast" value; at the "slow" setting the long-term average of the pipette current is forced to be zero, whereas at the "fast" setting it is possible to measure the potential at the pipette tip at zero current.

Abstract: Disclosed is a method of measuring the effective power absorbed by a resistive device such as an electroexplosive (or substitute) device due to radio-frequency (rf) energy induced in an electrical line connected to the device. The method comprises calibrating a device by passing dc currents of known value through it and measuring the voltage across it. Knowing the voltage and current, one can calculate resistance and power dissipation. By then connecting the device to an electrical line, one can measure the power dissipation and resistance and subtract the power dissipation due to the dc current to obtain the power dissipation due to rf power on the electrical line.

Abstract: An automatic calibration system for signal amplifier circuits uses a single complex power signal to replace the formerly used four separate sinewave frequencies and a square wave signal. In the illustrated embodiment of the invention, the power signal is recorded on a magnetic tape and is played back through reproduce equalizer circuits which apply the reproduced signal to a tracking frequency converter to produce an amplitude measurement of each of the preselected frequency components forming the complex power signal. The amplitude measurements are referenced to the power signal's actual harmonic content to enable an adjustment of the equalizer circuits to produce a minimum error in the playback signal. A bandpass phase response measurement is also performed on the reproduced signal by comparing the phase difference between the reproduced signal and a synthesized power signal after the amplitude compensation produced by the amplitude measurements.

Abstract: A linearizing circuit (10) is disclosed for devices having logarithmic outputs, such as electrolytic oxygen detectors (12). The circuit (10) has an inverting biasing circuit (14) and a scaling circuit (16) connected to an antilog function generator (18) and is calibrated by zeroing the inverting biasing circuit (14) at an extreme point of the desired range and sealing a second point on the desired range in the scaling circuit (16).