Manual of U.S. Patent Classification
as of June 30, 2000

Class
324
ELECTRICITY: MEASURING AND TESTING

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Subclass		Title
ClassTitle		===> ELECTRICITY: MEASURING AND TESTING
300		PARTICLE PRECESSION RESONANCE
301		. Using a magnetometer
302		. . To determine direction
303		. Using well logging device
304		. Using optical pumping or sensing device
305		. . Having particular optical cell structure
306		. Determine fluid flow rate
307		. Using a nuclear resonance spectrometer system
308		. . Including a test sample and control sample
309		. . To obtain localized resonance within a sample
310		. . By scanning sample frequency spectrum
311		. . With signal decoupling
312		. . By spectrum storage and analysis
313		. . Including polarizing magnetic field/radio frequency tuning
314		. . With conditioning of transmitter signal
315		. . With sample resonant frequency and temperature interdependence
316		. Using an electron resonance spectrometer system
317		. . Including a test sample and control sample
318		. Spectrometer components
319		. . Polarizing field magnet
320		. . . With homogeneity control
321		. . Sample holder structure
322		. . Electronic circuit elements
323		OF GEOPHYSICAL SURFACE OR SUBSURFACE IN SITU
324		. Including borehole fluid investigation
325		. . To determine fluid entry
326		. For small object detection or location
327		. . Using oscillator coupled search head
328		. . . Of the beat frequency type
329		. . Using movable transmitter and receiver
330		. By aerial survey
331		. . For magnetic field detection
332		. With radiant energy or nonconductive-type transmitter
333		. . Within a borehole
334		. . With separate pickup
335		. . . Employing multiple frequencies
336		. . . To detect transient signals
337		. . . To detect return wave signals
338		. . . Within a borehole
339		. . . . By induction logging
340		. . . . . To measure susceptibility
341		. . . . . To measure dielectric constant
342		. . . . . Using a toroidal coil
343		. . . . . Using angularly spaced coils
344		. With radiant energy or nonconductive-type receiver
345		. By magnetic means
346		. . Within a borehole
347		. Using electrode arrays, circuits, structure, or supports
348		. . For detecting naturally occurring fields, currents, or potentials
349		. . . Of the telluric type
350		. . . . Including magneto-telluric type
351		. . . Within a borehole
352		. . . . Combined with artificial source measurement
353		. . . . With fluid movement or pressure variation
354		. . Coupled to artificial current source
355		. . . Within a borehole
356		. . . . While drilling
357		. . . Including separate pickup of generated fields or potentials
358		. . . . With three electrodes
359		. . . . With nonelectrode pickup means
360		. . . . Using a pulse-type current source
361		. . . . . With mechanical current reversing means
362		. . . . . To measure induced polarization
363		. . . . By varying the path of current flow
364		. . . . . Using frequency variation
365		. . . . Offshore
366		. . . . For well logging
367		. . . . . Using a pad member
368		. . . . . Cased borehole
369		. . . . . While drilling
370		. . . . . Using surface current electrodes
371		. . . . . Using plural fields
372		. . . . . Between spaced boreholes
373		. . . . . Using current focussing means
374		. . . . . . Including a pad member
375		. . . . . . Including plural current focussing arrays
376		OF SUBSURFACE CORE SAMPLE
377		. For magnetic properties
378		INTERNAL-COMBUSTION ENGINE IGNITION SYSTEM OR DEVICE
379		. With analysis of displayed waveform
380		. Electronic ignition system
381		. . With magnetically controlled circuit
382		. . With capacitor discharge circuit
383		. By simulating or substituting for a component under test
384		. Using plural tests in a conventional ignition system
385		. Distributor
386		. . Dwell (i.e., cam angle)
387		. . Condenser
388		. Coil
389		. Magneto
390		. Low or high tension lead
391		. Ignition timing
392		. . Using a pulse signal technique
393		. In situ testing of spark plug
394		. . With cathode-ray tube display
395		. . Using an illuminating device to indicate spark plug condition
396		. . With an air gap in series with spark plug to indicate spark plug condition
397		. . By shorting the plug to ground to indicate spark plug condition
398		. . . With air gap in ground circuit
399		. . Wherein a measured electric quantity indicates spark plug condition
400		. Spark plug removed or tested in a test fixture
401		. . Using a pressure chamber
402		. Apparatus for coupling a measuring instrument to an ignition system
403		ELECTRIC LAMP OR DISCHARGE DEVICE
404		. Cathode-ray tube
405		. Vacuum tube
406		. . Plural tubes in the testing circuit
407		. . Testing circuit for diverse-type tube
408		. . Circuit for making diverse test
409		. . Testing discharge space characteristic (e.g., emission)
410		. . . With application of current or potential to the discharge control means
411		. . . . Pulsating or alternating current or potential for the discharge control means
412		. . . . . Pulsating or alternating current for the anode
413		. . Shock testing
414		. Electric lamp
415		ELECTROMECHANICAL SWITCHING DEVICE
416		. Voltage regulator
417		. Thermostat switch
418		. Relay
419		. . Reed switch
420		. . To evaluate contact chatter
421		. . To evaluate contact resistance
422		. . To evaluate contact sequence of operation
423		. . To evaluate contact response time
424		. Circuit breaker
425		ELECTROLYTE PROPERTIES
426		. Using a battery testing device
427		. . To determine ampere-hour charge capacity
428		. . . Including an integrating device
429		. . To determine load/no-load voltage
430		. . To determine internal battery impedance
431		. . With temperature compensation of measured condition
432		. . To determine battery electrolyte condition
433		. . To compare battery voltage with a reference voltage
434		. . To determine plural cell condition
435		. . Having particular meter scale or indicator
436		. . Including oscillator in measurement circuit
437		. . Including probe structure
438		. Using a pH determining device
439		. Using a conductivity determining device
440		. . Which includes a dropping mercury cell
441		. . Which includes a temperature responsive element
442		. . Which includes an oscillator
443		. . Having a bridge circuit
444		. . Which includes current and voltage electrodes
445		. . Having inductance probe structure
446		. . Having conductance probe structure
447		. . . With movable or adjustable electrode
448		. . . With concentric electrodes
449		. . . With axially arranged electrodes
450		. . Which includes particular cell container structure
451		A MATERIAL PROPERTY USING THERMOELECTRIC PHENOMENON
452		A MATERIAL PROPERTY USING ELECTROSTATIC PHENOMENON
453		. In a liquid
454		. Frictionally induced
455		. Corona induced
456		. For flaw detection
457		ELECTROSTATIC FIELD
458		. Using modulation-type electrometer
459		USING IONIZATION EFFECTS
460		. For monitoring pressure
461		. . Using a radioactive substance
462		. . Using thermionic emissions
463		. . Using a magnetic field
464		. For analysis of gas, vapor, or particles of matter
465		. . Using electronegative gas sensor
466		. . Using a filter
467		. . Using test material desorption
468		. . Using thermal ionization
469		. . Using a radioactive substance
470		. . Using thermionic emission
200		MAGNETIC
201		. Susceptibility
202		. Calibration
203		. Curie point determination
204		. Fluid material examination
205		. Permanent magnet testing
206		. Movable random length material measurement
207.11		. Displacement
207.12		. . Compensation for measurement
207.13		. . Having particular sensor means
207.14		. . . Diverse sensors
207.15		. . . Inductive
207.16		. . . . Electrically energized
207.17		. . . . . Separate pick-up
207.18		. . . . . Differential type (e.g., LVDT)
207.19		. . . . . Differential bridge circuit
207.2		. . . Hall effect
207.21		. . . Magnetoresistive
207.22		. . Having particular sensed object
207.23		. . Plural measurements (e.g., linear and rotary)
207.24		. . Linear
207.25		. . Rotary
207.26		. . Approach or retreat
209		. Stress in material measurement
210		. Magnetic information storage element testing
211		. . Memory core storage element testing
212		. . Dynamic information element testing
213		. Magnetic recording medium on magnetized object records object field
214		. By paramagnetic particles
215		. . With pattern enhancing additive
216		. . Flaw testing
217		. Railroad rail flaw testing
218		. . Rail joint cutout
219		. Magnetic sensor within material
220		. . Sensor supported, positioned, or moved within pipe
221		. . . Borehole pipe testing
222		. Hysteresis or eddy current loss testing
223		. Hysteresis loop curve display or recording
224		. With temperature control of material or element of test circuit
225		. With compensation for test variable
226		. Combined
227		. Plural tests
228		. With means to create magnetic field to test material
229		. . Thickness measuring
230		. . . Layer or layered material
231		. . . With backing member
232		. . Plural magnetic fields in material
233		. . With phase sensitive element
234		. . Electrically energized nonforce type sensor
235		. . . Noncoil type
236		. . . Oscillator type
237		. . . . Material flaw testing
238		. . . Material flaw testing
239		. . Induced voltage-type sensor
240		. . . Material flaw testing
241		. . . . Opposed induced voltage sensors
242		. . . . Plural sensors
243		. . . Plural sensors
244		. Magnetometers
244.1		. . Optical
245		. . Plural sensor axis misalignment correction
246		. . With means to align field sensor with magnetic field sensed
247		. . Nonparallel plural magnetic sensors
248		. . Superconductive magnetometers
249		. . Thin film magnetometers
250		. . Electronic tube or microwave magnetometers
251		. . Hall plate magnetometers
252		. . Semiconductor type solid-state or magnetoresistive magnetometers
253		. . Saturable core magnetometers
254		. . . Second harmonic type
255		. . . Peak voltage type
256		. . Energized movable sensing coil magnetometers
257		. . Moving coil magnetometer
258		. . Fixed coil magnetometer
259		. . Movable magnet or magnetic member interacts with magnetic field
260		. Magnetic field detection devices
261		. . With support for article
262		. Magnetic test structure elements
263		. Current through test material forms test magnetic field
500		FAULT DETECTING IN ELECTRIC CIRCUITS AND OF ELECTRIC COMPONENTS
501		. Using radiant energy
502		. In an ignitor or detonator
503		. In vehicle wiring
504		. . With trailer
505		. . Combined with window glass
506		. Combined with a flashlight
507		. . With fuse testing attachment
508		. With electric power receptacle for line wire testing
509		. Of ground fault indication
510		. . Of electrically operated apparatus (power tool, appliance, machine, etc.)
511		. Of electrically operated apparatus (power tool, appliance, machine, etc.)
512		. For fault location
513		. . Where component moves while under test
514		. . . By exposing component to liquid or gas while under test
515		. . . Using a particular sensing electrode
516		. . . . Metal chain
517		. . . . Wire bristles
518		. . . . Metal pellets or beads
519		. . By capacitance measuring
520		. . By frequency sensitive or responsive detection
521		. . By phase sensitive or responsive detection
522		. . By voltage or current measuring
523		. . . Of an applied test signal
524		. . . Polarity responsive
525		. . By resistance or impedance measuring
526		. . . Using a bridge circuit
527		. . By applying a test signal
528		. . . Tracing test signal to fault location
529		. . . . Using a magnetic field sensor
530		. . . . Using an electric field sensor
531		. . . At fault site
532		. . . Using time measuring
533		. . . . Of reflected test signal
534		. . By reflection technique
535		. . By time measuring
536		. . By spark or arc discharge
537		. Of individual circuit component or element
750		. . System sensing fields adjacent device under test (DUT)
751		. . . Using electron beam probe
752		. . . Using light probe
753		. . . Using electro-optic device
754		. . With probe elements
755		. . . Internal of or on support for device under test (DUT)
756		. . . Contact confirmation
757		. . . Probe contact enhancement
758		. . . Probe alignment or positioning
759		. . . With recording of test results on DUT
760		. . . With temperature control
761		. . . Pin
762		. . . Cantilever
763		. . DUT including test circuit
764		. . With identification of DUT
765		. . Test of semiconductor device
766		. . . With barrier layer
767		. . . . Diode
768		. . . . Bipolar transistor
769		. . . . Field effect transistor
770		. . Liquid crystal device test
771		. . Power supply test
772		. . Motor or generator fault tests
538		. . Electrical connectors
539		. . Multiconductor cable
540		. . . With sequencer
541		. . . For insulation fault
542		. . . Having a light or sound indicator
543		. . Single conductor cable
544		. . . For insulation fault
545		. . Armature or rotor
546		. . Winding or coil
547		. . . Transformer
548		. . Capacitor
549		. . Resistor
550		. . Fuse
551		. . Insulation
552		. . . Bushing
553		. . . Oil
554		. . . Sheet material
555		. Instruments and devices for fault testing
556		. . Having a lamp or light indicator
557		FOR INSULATION FAULT OF NONCIRCUIT ELEMENTS
558		. Where element moves while under test
559		. Where a moving sensing electrode scans a stationary element under test
600		IMPEDANCE, ADMITTANCE OR OTHER QUANTITIES REPRESENTATIVE OF ELECTRICAL STIMULUS/RESPONSE RELATIONSHIPS
601		. Calibration
602		. With auxiliary means to condition stimulus/response signals
603		. . For excitation
604		. . . Including marker signal generator circuit
605		. . For response signal evaluation or processing
606		. . . Including a signal comparison circuit
607		. . . Including a conversion (e.g., A->D or D-> A) process
608		. . . Including a ratiometric function
609		. . For sensing
610		. . . Including a bridge circuit
611		. . . Including a remote type circuit
612		. Parameter related to the reproduction or fidelity of a signal affected by a circuit under test
613		. . Noise
614		. . . Signal to noise ratio or noise figure
615		. . Transfer function type characteristics
616		. . . Gain or attenuation
617		. . . Response time or phase delay
618		. . . Transient response or transient recovery time (e.g., damping)
619		. . . Selective type characteristics
620		. . Distortion
621		. . . Envelope delay
622		. . . Phase
623		. . . Harmonic
624		. . . Intermodulation
625		. . . Dissymmetry or asymmetry
626		. . . Nonlinearity
627		. . Shielding effectiveness (SE)
628		. . . Circuit interference (e.g., crosstalk) measurement
629		. Distributive type parameters
630		. . Plural diverse parameters
631		. . Using wave polarization (e.g., field rotation)
632		. . Using particular field coupling type (e.g., fringing field)
633		. . Using resonant frequency
634		. . . To determine water content
635		. . . To determine dimension (e.g., distance or thickness)
636		. . . With a resonant cavity
637		. . Using transmitted or reflected microwaves
638		. . . Scattering type parameters (e.g., complex reflection coefficient)
639		. . . Where energy is transmitted through a test substance
640		. . . . To determine water content
641		. . . . To determine insertion loss
642		. . . Where energy is reflected (e.g., reflectometry)
643		. . . . To determine water content
644		. . . . To determine dimension (e.g., distance or thickness)
645		. . . . Having standing wave pattern
646		. . . . To determine reflection coefficient
647		. . Using a comparison or difference circuit
648		. . . With a bridge circuit
649		. Lumped type parameters
650		. . Using phasor or vector analysis
651		. . . With a bridge circuit
652		. . Of a resonant circuit
653		. . For figure of merit or Q value
654		. . Using inductive type measurement
655		. . . Including a tuned or resonant circuit
656		. . . Including a comparison or difference circuit
657		. . . . Using a bridge circuit
658		. . Using capacitive type measurement
659		. . . With loss characteristic evaluation
660		. . . With variable electrode area
661		. . . With variable distance between capacitor electrodes
662		. . . . To determine dimension (e.g., thickness or distance)
663		. . . Where a material or object forms part of the dielectric being measured
664		. . . . To determine water content
665		. . . . . By comparison or difference circuit
666		. . . . . . Including a bridge circuit
667		. . . . . By frequency signal response, change or processing circuit
668		. . . . . . Including a tuned or resonant circuit
669		. . . . . With compensation means
670		. . . . . . For temperature variations
671		. . . . To determine dimension (e.g., dielectric thickness)
672		. . . . By comparison or difference circuit
673		. . . . . Including a bridge circuit
674		. . . . By frequency signal response, change or processing circuit
675		. . . . . Including a tuned or resonant circuit
676		. . . With pulse signal processing circuit
677		. . . . Including R/C time constant circuit
678		. . . . Including charge or discharge cycle circuit
679		. . . With comparison or difference circuit
680		. . . . Including a bridge circuit
681		. . . With frequency signal response, change or processing circuit
682		. . . . Including a tuned or resonant circuit
683		. . . With phase signal processing circuit
684		. . . With compensation means
685		. . . . For temperature variation
686		. . . With a capacitive sensing means
687		. . . . Having fringing field coupling
688		. . . . Including a guard or ground electrode
689		. . . . To determine water content
690		. . . . Including a probe type structure
691		. . Using resistance or conductance measurement
692		. . . With living organism condition determination using conductivity effects
693		. . . With object or substance characteristic determination using conductivity effects
694		. . . . To determine water content
695		. . . . . Where the object moves while under test
696		. . . . . With a probe structure
697		. . . . For interface
698		. . . . To determine oil qualities
699		. . . . To determine dimension (e.g., distance or thickness)
700		. . . . . Including corrosion or erosion
701		. . . . Where the object moves while under test
702		. . . With radiant energy effects
703		. . . . Including heating
704		. . . With ratio determination
705		. . . With comparison or difference circuit
706		. . . . Including a bridge circuit
707		. . . With frequency response, change or processing circuit
708		. . . . Including a tuned or resonant circuit
709		. . . With phase signal processing circuit
710		. . . With pulse signal processing circuit
711		. . . . Including R/C time constant circuit
712		. . . . Including a digital or logic circuit
713		. . . With voltage or current signal evaluation
714		. . . . Including a potentiometer
715		. . . . Including a particular probing technique (e.g., four point probe)
716		. . . . . To determine dimension (e.g., distance or thickness)
717		. . . . . To determine material composition
718		. . . . . To detect a flaw or defect
719		. . . With semiconductor or IC materials quality determination using conductivity effects
720		. . . With compensation means
721		. . . . For temperature variation
722		. . . Device or apparatus determines conductivity effects
723		. . . . Potentiometer
724		. . . . Using a probe type structure
725		. Using a particular bridge circuit
726		. Transformer testing (e.g., ratio)
727		. Piezoelectric crystal testing (e.g., frequency, resistance)
66		CONDUCTOR IDENTIFICATION OR LOCATION (E.G., PHASE IDENTIFICATION)
67		. Inaccessible (at test point) conductor (e.g., buried in wall)
160		ELECTRICAL SPEED MEASURING
161		. Speed comparing means
162		. With acceleration measuring means
163		. Including speed analog electrical signal generator
164		. . Eddy current generator type (e.g., tachometer)
165		. . With direction indicator
166		. Including speed-related frequency generator
167		. . Including rotating magnetic field actuated indicator
168		. . Including periodic switch
169		. . . In ignition system
170		. . . . High voltage speed signal type
171		. . . With extent-of-travel indicator
172		. . Including synchronized recording medium
173		. . Including magnetic detector
174		. . . Permanent magnet type
175		. . Including radiant energy detector
176		. Including object displacement varied variable circuit impedance
177		. Including motor current or voltage sensor
178		. Including "event" sensing means
179		. . Magnetic field sensor
180		. . Mechanically actuated switch
71.1		DETERMINING NONELECTRIC PROPERTIES BY MEASURING ELECTRIC PROPERTIES
71.2		. Erosion
71.3		. Beam of atomic particles
71.4		. Particle counting
71.5		. Semiconductors for nonelectrical property
71.6		. Superconductors
72		TESTING POTENTIAL IN SPECIFIC ENVIRONMENT (E.G., LIGHTNING STROKE)
72.5		. Voltage probe
73.1		PLURAL, AUTOMATICALLY SEQUENTIAL TESTS
74		TESTING AND CALIBRATING ELECTRIC METERS (E.G., WATT-HOUR METERS)
75		. By stroboscopic means
76.11		MEASURING, TESTING, OR SENSING ELECTRICITY, PER SE
76.12		. Analysis of complex waves
76.13		. . Amplitude distribution
76.14		. . . Radiometer (e.g., microwave, etc.)
76.15		. . . With sampler
76.16		. . . With counter
76.17		. . . With integrator
76.18		. . . With slope detector
76.19		. . Frequency spectrum analyzer
76.21		. . . By Fourier analysis
76.22		. . . Real-time spectrum analyzer
76.23		. . . With mixer
76.24		. . . With sampler
76.25		. . . With slope detector
76.26		. . . Scanning-panoramic receiver
76.27		. . . . With particular sweep circuit
77.11		. . . Nonscanning
76.28		. . . . Digital filter
76.29		. . . . With filtering
76.31		. . . . . Parallel filters
76.32		. . . . . . With space discharge device
76.33		. . . . Correlation
76.34		. . . . . With space discharge device
76.35		. . . . With delay line
76.36		. . . . With optics
76.37		. . . . . Bragg cell
76.38		. . With sampler
76.39		. Frequency of cyclic current or voltage (e.g., cyclic counting etc.)
76.41		. . Frequency comparison, (e.g., heterodyne, etc.)
76.42		. . . With sampler
76.43		. . . With plural mixers
76.44		. . . With filtering
76.45		. . . . Bandpass
76.46		. . . . Plural
76.47		. . . Digital output
76.48		. . . . With counter
76.49		. . Tuned mechanical resonator (e.g., reed, piezocrystal, etc.)
76.51		. . By tuning (e.g., to resonance,etc.)
76.52		. . By phase comparison
76.53		. . . With phase lock
76.54		. . . With delay line
76.55		. . . Digital output
76.56		. . . . With microwave frequency detection
76.57		. . . . With tone detection
76.58		. . . . With sampler
76.59		. . . . With multiplexing
76.61		. . . . With memory
76.62		. . . . With counter
76.63		. . . . . Using register
76.64		. . . . . Plural
76.65		. . . . With space discharge device
76.66		. . . With capacitive energy storage
76.67		. . . . With space discharge device
76.68		. . . With filtering
76.69		. . . Current output proportional to frequency
76.71		. . . Nulling circuit
76.72		. . . Qualitative output
76.73		. . . With saturable device
76.74		. . . Deviation measurement
76.75		. . Having inductive sensing
76.76		. . With space discharge device
76.77		. Phase comparison (e.g., between cyclic pulse voltage and sinusoidal current, etc.)
76.78		. . Quadrature sensing
76.79		. . Feedback control, electrical
76.81		. . Feedback control, mechanical
76.82		. . Digital output
76.83		. . Analog output
84		. . With waveguide (e.g., coaxial cable)
85		. . With frequency conversion
86		. . Polyphase (e.g., phase angle, phase rotation or sequence)
87		. . With nonlinear device (e.g., saturable reactor, rectifier), discharge device (e.g., gas tube) or lamp
88		. . . Cathode ray
89		. . . Space discharge control means (e.g., grid)
90		. . Electrodynamometer instrument
91		. . Synchroscope type
92		. Fluid (e.g., thermal expansion)
93		. . Conductive field (e.g., mercury)
94		. . . Electrolytic
95		. With waveguide or long line
96		. Using radiant energy
97		. . Light beam type (e.g., mirror galvanometer, parallax-free scale)
98		. Balancing (e.g., known/unknown voltage comparison, bridge, rebalancing)
99R		. . Automatic
100		. . . With recording
99D		. . . Digital voltmeters
101		. Non-rebalancing bridge
102		. Transient or portion of cyclic
103R		. Demand, excess, maximum or minimum (e.g., separate meters for positive and negative power, peak voltmeter)
104		. . Thermal (e.g., actuation)
103P		. . Peak voltmeters
105		. Thermal (e.g., compensation)
106		. . Actuation
107		. Polyphase
108		. . Positive, negative or zero sequence
109		. Electrostatic attraction or piezoelectric
110		. Meter protection or fraud combatting
111		. With storage means for voltage or current (e.g., condenser banks)
112		. . Tape, sheet (e.g., disk) or wire (e.g., magnetic) storage
113		. Recording
114		. Plural meters (e.g., plural movements in one case)
115		. Plural ranges, scales or registration rates
116		. . With register (e.g., discount type, demand penalty)
117R		. Magnetic saturation (e.g., in field or in amplifier)
117H		. . Hall effect
118		. Modulator/demodulator
119		. With rectifier (e.g., A.C. to D.C.)
120		. With voltage or current conversion (e.g., D.C. to A.C., 60 to 1000)
121R		. Cathode ray (e.g., magic eye)
121E		. . Magic eye indicators
122		. Gaseous discharge (e.g., spark gap voltmeter)
123R		. With amplifier or space discharge device
124		. . Inverted amplifier
123C		. . Feedback amplifiers
125		. Inertia control, instrument damping and vibration damping
126		. With coupling means (e.g., attenuator, shunt)
127		. . Transformer (e.g., split core admits conductor carrying unknown current)
128		. . Selective filter
129		. Polepiece (e.g., split) admits nonunitary input conductor
130		. Self-calibration
131		. Suppressed zero
132		. Nonlinear (e.g., Thyrite)
133		. Nonquantitative (e.g., hot-line indicator, polarity tester)
134		. With commutator or reversing or pulsating switch (e.g., D.C. watt-hour meter)
135		. . Oscillating
136		. With rolling wheel or ball (e.g., transmission, integrating)
137		. Eddy current rotor (e.g., A.C. integrating wattmeter)
138		. . With phase adjustment
139		. Motor-driven, time-controlled or oscillating (e.g., ratchet)
140R		. Plural inputs (e.g., summation, ratio)
141		. . Voltamperes (real or reactive)
142		. . Watts
140D		. . Ratio
143		. Plural active motor elements (e.g., for two crossed pointers)
144		. With electromagnetic field (e.g., dynamometer)
145		. . Solenoid plunger type
146		. . With permanent magnet (e.g., field, vane)
147		. . Soft iron vane
149		. With probe, prod or terminals
150		. Eccentrically pivoted coil
151R		. With permanent magnet
152		. . Drag magnet
151A		. . Permanent magnet core
153		. With register
154R		. With rotor (e.g., filar suspension, zero set, balancing)
155		. . With pivot (e.g., internal friction compensation, anticreep)
154PB		. . Pointer and bearing details
156		. Casings
157		. Combined
158.1		MISCELLANEOUS
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		CROSS-REFERENCE ART COLLECTION
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800		DIVINING RODS

Information Products Division -- Contacts

Questions regarding this report should be directed to:

U.S. Patent and Trademark Office
Information Products Division
PK3- Suite 441
Washington, DC 20231

tel: (703) 306-2600
FAX: (703) 306-2737
email: oeip@uspto.gov

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Last Modified: 6 October 2000