Class Number |
Class Name |
No. of Patents |
324/452 |
A material property using electrostatic phenomenon |
159 |
324/455 |
Corona induced |
64 |
324/456 |
For flaw detection |
64 |
324/454 |
Frictionally induced |
52 |
324/453 |
In a liquid |
81 |
324/451 |
A material property using thermoelectric phenomenon |
31 |
324/66 |
Conductor identification or location (e.g., phase identification) |
305 |
324/67 |
Inaccessible (at test point) conductor (e.g., buried in wall) |
359 |
324/71.1 |
Determining nonelectric properties by measuring electric properties |
692 |
324/71.3 |
Beam of atomic particles |
116 |
324/71.2 |
Erosion |
141 |
324/71.4 |
Particle counting |
239 |
324/71.5 |
Semiconductors for nonelectrical property |
190 |
324/71.6 |
Superconductors |
43 |
324/800 |
Divining rods |
1 |
324/403 |
Electric lamp or discharge device |
42 |
324/404 |
Cathode-ray tube |
56 |
324/414 |
Electric lamp |
124 |
324/405 |
Vacuum tube |
8 |
324/408 |
Circuit for making diverse test |
2 |
324/406 |
Plural tubes in the testing circuit |
2 |
324/413 |
Shock testing |
1 |
324/407 |
Testing circuit for diverse-type tube |
5 |
324/409 |
Testing discharge space characteristic (e.g., emission) |
20 |
324/410 |
With application of current or potential to the discharge control means |
15 |
324/411 |
Pulsating or alternating current or potential for the discharge control means |
5 |
324/412 |
Pulsating or alternating current for the anode |
4 |
324/160 |
Electrical speed measuring |
273 |
324/178 |
Including "event" sensing means |
70 |
324/179 |
Magnetic field sensor |
85 |
324/180 |
Mechanically actuated switch |
7 |
324/177 |
Including motor current or voltage sensor |
66 |
324/176 |
Including object displacement varied variable circuit impedance |
25 |
324/163 |
Including speed analog electrical signal generator |
93 |
324/164 |
Eddy current generator type (e.g., tachometer) |
52 |
324/165 |
With direction indicator |
114 |
324/166 |
Including speed-related frequency generator |
469 |
324/173 |
Including magnetic detector |
434 |
324/174 |
Permanent magnet type |
685 |
324/168 |
Including periodic switch |
34 |
324/169 |
In ignition system |
43 |
324/170 |
High voltage speed signal type |
10 |
324/171 |
With extent-of-travel indicator |
36 |
324/175 |
Including radiant energy detector |
135 |
324/167 |
Including rotating magnetic field actuated indicator |
64 |
324/172 |
Including synchronized recording medium |
16 |
324/161 |
Speed comparing means |
145 |
324/162 |
With acceleration measuring means |
67 |
324/425 |
Electrolyte properties |
247 |
324/426 |
Using a battery testing device |
693 |
324/435 |
Having particular meter scale or indicator |
123 |
324/436 |
Including oscillator in measurement circuit |
51 |
324/437 |
Including probe structure |
57 |
324/433 |
To compare battery voltage with a reference voltage |
441 |
324/427 |
To determine ampere-hour charge capacity |
436 |
324/428 |
Including an integrating device |
128 |
324/432 |
To determine battery electrolyte condition |
116 |
324/430 |
To determine internal battery impedance |
263 |
324/429 |
To determine load/no-load voltage |
214 |
324/434 |
To determine plural cell condition |
257 |
324/431 |
With temperature compensation of measured condition |
118 |
324/439 |
Using a conductivity determining device |
333 |
324/443 |
Having a bridge circuit |
30 |
324/446 |
Having conductance probe structure |
139 |
324/449 |
With axially arranged electrodes |
65 |
324/448 |
With concentric electrodes |
44 |
324/447 |
With movable or adjustable electrode |
40 |
324/445 |
Having inductance probe structure |
72 |
324/440 |
Which includes a dropping mercury cell |
6 |
324/441 |
Which includes a temperature responsive element |
85 |
324/442 |
Which includes an oscillator |
74 |
324/444 |
Which includes current and voltage electrodes |
122 |
324/450 |
Which includes particular cell container structure |
141 |
324/438 |
Using a ph determining device |
166 |
324/415 |
Electromechanical switching device |
153 |
324/424 |
Circuit breaker |
202 |
324/418 |
Relay |
135 |
324/419 |
Reed switch |
19 |
324/420 |
To evaluate contact chatter |
15 |
324/421 |
To evaluate contact resistance |
38 |
324/423 |
To evaluate contact response time |
47 |
324/422 |
To evaluate contact sequence of operation |
35 |
324/417 |
Thermostat switch |
22 |
324/416 |
Voltage regulator |
34 |
324/457 |
Electrostatic field |
319 |
324/458 |
Using modulation-type electrometer |
147 |
324/500 |
Fault detecting in electric circuits and of electric components |
424 |
324/506 |
Combined with a flashlight |
16 |
324/507 |
With fuse testing attachment |
21 |
324/512 |
For fault location |
238 |
324/527 |
By applying a test signal |
332 |
324/531 |
At fault site |
42 |
324/528 |
Tracing test signal to fault location |
103 |
324/529 |
Using a magnetic field sensor |
170 |
324/530 |
Using an electric field sensor |
67 |
324/532 |
Using time measuring |
98 |
324/533 |
Of reflected test signal |
246 |
324/519 |
By capacitance measuring |
172 |
324/520 |
By frequency sensitive or responsive detection |
181 |
324/521 |
By phase sensitive or responsive detection |
125 |
324/534 |
By reflection technique |
230 |
324/525 |
By resistance or impedance measuring |
360 |
324/526 |
Using a bridge circuit |
38 |
324/536 |
By spark or arc discharge |
344 |
324/535 |
By time measuring |
109 |
324/522 |
By voltage or current measuring |
823 |
324/523 |
Of an applied test signal |
217 |
324/524 |
Polarity responsive |
57 |
324/513 |
Where component moves while under test |
14 |
324/514 |
By exposing component to liquid or gas while under test |
55 |
324/515 |
Using a particular sensing electrode |
48 |
324/516 |
Metal chain |
8 |
324/518 |
Metal pellets or beads |
6 |
324/517 |
Wire bristles |
8 |
324/502 |
In an ignitor or detonator |
33 |
324/503 |
In vehicle wiring |
196 |
324/505 |
Combined with window glass |
16 |
324/504 |
With trailer |
44 |
324/555 |
Instruments and devices for fault testing |
281 |
324/556 |
Having a lamp or light indicator |
200 |
324/511 |
Of electrically operated apparatus (power tool, appliance, machine, etc.) |
160 |
324/509 |
Of ground fault indication |
411 |
324/510 |
Of electrically operated apparatus (power tool, appliance, machine, etc.) |
161 |
324/537 |
Of individual circuit component or element |
1254 |
324/545 |
Armature or rotor |
146 |
324/548 |
Capacitor |
191 |
324/763 |
Dut including test circuit |
1087 |
324/538 |
Electrical connectors |
437 |
324/550 |
Fuse |
111 |
324/551 |
Insulation |
305 |
324/552 |
Bushing |
32 |
324/553 |
Oil |
21 |
324/554 |
Sheet material |
21 |
324/770 |
Liquid crystal device test |
415 |
324/772 |
Motor or generator fault tests |
445 |
324/539 |
Multiconductor cable |
334 |
324/541 |
For insulation fault |
121 |
324/542 |
Having a light or sound indicator |
109 |
324/540 |
With sequencer |
53 |
324/771 |
Power supply test |
142 |
324/549 |
Resistor |
60 |
324/543 |
Single conductor cable |
170 |
324/544 |
For insulation fault |
130 |
324/750 |
System sensing fields adjacent device under test (dut) |
378 |
324/753 |
Using electro-optic device |
211 |
324/751 |
Using electron beam probe |
399 |
324/752 |
Using light probe |
338 |
324/765 |
Test of semiconductor device |
3698 |
324/766 |
With barrier layer |
124 |
324/768 |
Bipolar transistor |
65 |
324/767 |
Diode |
217 |
324/769 |
Field effect transistor |
386 |
324/546 |
Winding or coil |
189 |
324/547 |
Transformer |
135 |
324/764 |
With identification of dut |
68 |
324/754 |
With probe elements |
3069 |
324/762 |
Cantilever |
445 |
324/756 |
Contact confirmation |
152 |
324/755 |
Internal of or on support for device under test (dut) |
960 |
324/761 |
Pin |
940 |
324/758 |
Probe alignment or positioning |
971 |
324/757 |
Probe contact enhancement |
424 |
324/759 |
With recording of test results on dut |
53 |
324/760 |
With temperature control |
797 |
324/501 |
Using radiant energy |
240 |
324/508 |
With electric power receptacle for line wire testing |
140 |
324/557 |
For insulation fault of noncircuit elements |
179 |
324/559 |
Where a moving sensing electrode scans a stationary element under test |
60 |
324/558 |
Where element moves while under test |
45 |
324/600 |
Impedance, admittance or other quantities representative of electrical stimulus/response relationships |
181 |
324/601 |
Calibration |
608 |
324/629 |
Distributive type parameters |
93 |
324/630 |
Plural diverse parameters |
26 |
324/647 |
Using a comparison or difference circuit |
100 |
324/648 |
With a bridge circuit |
31 |
324/632 |
Using particular field coupling type (e.g., fringing field) |
148 |
324/633 |
Using resonant frequency |
173 |
324/635 |
To determine dimension (e.g., distance or thickness) |
86 |
324/634 |
To determine water content |
68 |
324/636 |
With a resonant cavity |
193 |
324/637 |
Using transmitted or reflected microwaves |
411 |
324/638 |
Scattering type parameters (e.g., complex reflection coefficient) |
209 |
324/642 |
Where energy is reflected (e.g., reflectometry) |
397 |
324/645 |
Having standing wave pattern |
41 |
324/644 |
To determine dimension (e.g., distance or thickness) |
224 |
324/646 |
To determine reflection coefficient |
86 |
324/643 |
To determine water content |
140 |
324/639 |
Where energy is transmitted through a test substance |
271 |
324/641 |
To determine insertion loss |
27 |
324/640 |
To determine water content |
188 |
324/631 |
Using wave polarization (e.g., field rotation) |
39 |
324/649 |
Lumped type parameters |
122 |
324/653 |
For figure of merit or q value |
26 |
324/652 |
Of a resonant circuit |
81 |
324/658 |
Using capacitive type measurement |
617 |
324/663 |
Where a material or object forms part of the dielectric being measured |
530 |
324/672 |
By comparison or difference circuit |
84 |
324/673 |
Including a bridge circuit |
23 |
324/674 |
By frequency signal response, change or processing circuit |
95 |
324/675 |
Including a tuned or resonant circuit |
44 |
324/671 |
To determine dimension (e.g., dielectric thickness) |
229 |
324/664 |
To determine water content |
232 |
324/665 |
By comparison or difference circuit |
49 |
324/666 |
Including a bridge circuit |
18 |
324/667 |
By frequency signal response, change or processing circuit |
92 |
324/668 |
Including a tuned or resonant circuit |
49 |
324/669 |
With compensation means |
37 |
324/670 |
For temperature variations |
48 |
324/686 |
With a capacitive sensing means |
507 |
324/687 |
Having fringing field coupling |
142 |
324/688 |
Including a guard or ground electrode |
210 |
324/690 |
Including a probe type structure |
408 |
324/689 |
To determine water content |
146 |
324/679 |
With comparison or difference circuit |
270 |
324/680 |
Including a bridge circuit |
36 |
324/684 |
With compensation means |
109 |
324/685 |
For temperature variation |
56 |
324/681 |
With frequency signal response, change or processing circuit |
137 |
324/682 |
Including a tuned or resonant circuit |
71 |
324/659 |
With loss characteristic evaluation |
45 |
324/683 |
With phase signal processing circuit |
100 |
324/676 |
With pulse signal processing circuit |
114 |
324/678 |
Including charge or discharge cycle circuit |
397 |
324/677 |
Including r/c time constant circuit |
90 |
324/661 |
With variable distance between capacitor electrodes |
328 |
324/662 |
To determine dimension (e.g., thickness or distance) |
507 |
324/660 |
With variable electrode area |
186 |
324/654 |
Using inductive type measurement |
139 |
324/656 |
Including a comparison or difference circuit |
46 |
324/657 |
Using a bridge circuit |
19 |
324/655 |
Including a tuned or resonant circuit |
82 |
324/650 |
Using phasor or vector analysis |
125 |
324/651 |
With a bridge circuit |
13 |
324/691 |
Using resistance or conductance measurement |
386 |
324/722 |
Device or apparatus determines conductivity effects |
80 |
324/723 |
Potentiometer |
29 |
324/724 |
Using a probe type structure |
143 |
324/705 |
With comparison or difference circuit |
132 |
324/706 |
Including a bridge circuit |
103 |
324/720 |
With compensation means |
75 |
324/721 |
For temperature variation |
85 |
324/707 |
With frequency response, change or processing circuit |
68 |
324/708 |
Including a tuned or resonant circuit |
30 |
324/692 |
With living organism condition determination using conductivity effects |
152 |
324/693 |
With object or substance characteristic determination using conductivity effects |
329 |
324/697 |
For interface |
31 |
324/699 |
To determine dimension (e.g., distance or thickness) |
104 |
324/700 |
Including corrosion or erosion |
220 |
324/698 |
To determine oil qualities |
173 |
324/694 |
To determine water content |
198 |
324/695 |
Where the object moves while under test |
37 |
324/696 |
With a probe structure |
147 |
324/701 |
Where the object moves while under test |
53 |
324/709 |
With phase signal processing circuit |
51 |
324/710 |
With pulse signal processing circuit |
43 |
324/712 |
Including a digital or logic circuit |
47 |
324/711 |
Including r/c time constant circuit |
64 |
324/702 |
With radiant energy effects |
30 |
324/703 |
Including heating |
66 |
324/704 |
With ratio determination |
42 |
324/719 |
With semiconductor or ic materials quality determination using conductivity effects |
303 |
324/713 |
With voltage or current signal evaluation |
590 |
324/715 |
Including a particular probing technique (e.g., four point probe) |
218 |
324/718 |
To detect a flaw or defect |
178 |
324/716 |
To determine dimension (e.g., distance or thickness) |
150 |
324/717 |
To determine material composition |
101 |
324/714 |
Including a potentiometer |
57 |
324/612 |
Parameter related to the reproduction or fidelity of a signal affected by a circuit under test |
91 |
324/620 |
Distortion |
87 |
324/625 |
Dissymmetry or asymmetry |
12 |
324/621 |
Envelope delay |
29 |
324/623 |
Harmonic |
73 |
324/624 |
Intermodulation |
36 |
324/626 |
Nonlinearity |
26 |
324/622 |
Phase |
60 |
324/613 |
Noise |
213 |
324/614 |
Signal to noise ratio or noise figure |
73 |
324/627 |
Shielding effectiveness (se) |
147 |
324/628 |
Circuit interference (e.g., crosstalk) measurement |
117 |
324/615 |
Transfer function type characteristics |
112 |
324/616 |
Gain or attenuation |
58 |
324/617 |
Response time or phase delay |
119 |
324/619 |
Selective type characteristics |
39 |
324/618 |
Transient response or transient recovery time (e.g., damping) |
31 |
324/727 |
Piezoelectric crystal testing (e.g., frequency, resistance) |
103 |
324/726 |
Transformer testing (e.g., ratio) |
57 |
324/725 |
Using a particular bridge circuit |
133 |
324/602 |
With auxiliary means to condition stimulus/response signals |
48 |
324/603 |
For excitation |
112 |
324/604 |
Including marker signal generator circuit |
10 |
324/605 |
For response signal evaluation or processing |
135 |
324/607 |
Including a conversion (e.g., a->d or d-> a) process |
141 |
324/608 |
Including a ratiometric function |
48 |
324/606 |
Including a signal comparison circuit |
112 |
324/609 |
For sensing |
81 |
324/610 |
Including a bridge circuit |
49 |
324/611 |
Including a remote type circuit |
75 |
324/378 |
Internal-combustion engine ignition system or device |
114 |
324/402 |
Apparatus for coupling a measuring instrument to an ignition system |
153 |
324/383 |
By simulating or substituting for a component under test |
10 |
324/388 |
Coil |
99 |
324/385 |
Distributor |
9 |
324/387 |
Condenser |
2 |
324/386 |
Dwell (i.e., cam angle) |
13 |
324/380 |
Electronic ignition system |
102 |
324/382 |
With capacitor discharge circuit |
26 |
324/381 |
With magnetically controlled circuit |
12 |
324/391 |
Ignition timing |
66 |
324/392 |
Using a pulse signal technique |
65 |
324/393 |
In situ testing of spark plug |
69 |
324/397 |
By shorting the plug to ground to indicate spark plug condition |
11 |
324/398 |
With air gap in ground circuit |
3 |
324/395 |
Using an illuminating device to indicate spark plug condition |
21 |
324/399 |
Wherein a measured electric quantity indicates spark plug condition |
155 |
324/396 |
With an air gap in series with spark plug to indicate spark plug condition |
6 |
324/394 |
With cathode-ray tube display |
6 |
324/390 |
Low or high tension lead |
16 |
324/389 |
Magneto |
5 |
324/400 |
Spark plug removed or tested in a test fixture |
6 |
324/401 |
Using a pressure chamber |
4 |
324/384 |
Using plural tests in a conventional ignition system |
60 |
324/379 |
With analysis of displayed waveform |
96 |
324/200 |
Magnetic |
110 |
324/214 |
By paramagnetic particles |
18 |
324/216 |
Flaw testing |
49 |
324/215 |
With pattern enhancing additive |
9 |
324/202 |
Calibration |
354 |
324/226 |
Combined |
409 |
324/203 |
Curie point determination |
12 |
324/263 |
Current through test material forms test magnetic field |
67 |
324/207.11 |
Displacement |
241 |
324/207.26 |
Approach or retreat |
407 |
324/207.12 |
Compensation for measurement |
535 |
324/207.22 |
Having particular sensed object |
565 |
324/207.13 |
Having particular sensor means |
431 |
324/207.14 |
Diverse sensors |
94 |
324/207.2 |
Hall effect |
988 |
324/207.15 |
Inductive |
414 |
324/207.16 |
Electrically energized |
507 |
324/207.19 |
Differential bridge circuit |
85 |
324/207.18 |
Differential type (e.g., lvdt) |
200 |
324/207.17 |
Separate pick-up |
502 |
324/207.21 |
Magnetoresistive |
885 |
324/207.24 |
Linear |
791 |
324/207.23 |
Plural measurements (e.g., linear and rotary) |
188 |
324/207.25 |
Rotary |
1864 |
324/204 |
Fluid material examination |
252 |
324/223 |
Hysteresis loop curve display or recording |
38 |
324/222 |
Hysteresis or eddy current loss testing |
67 |
324/260 |
Magnetic field detection devices |
588 |
324/261 |
With support for article |
91 |
324/210 |
Magnetic information storage element testing |
277 |
324/212 |
Dynamic information element testing |
267 |
324/211 |
Memory core storage element testing |
16 |
324/213 |
Magnetic recording medium on magnetized object records object field |
34 |
324/219 |
Magnetic sensor within material |
101 |
324/220 |
Sensor supported, positioned, or moved within pipe |
299 |
324/221 |
Borehole pipe testing |
69 |
324/262 |
Magnetic test structure elements |
504 |
324/244 |
Magnetometers |
495 |
324/250 |
Electronic tube or microwave magnetometers |
28 |
324/256 |
Energized movable sensing coil magnetometers |
22 |
324/258 |
Fixed coil magnetometer |
96 |
324/251 |
Hall plate magnetometers |
372 |
324/259 |
Movable magnet or magnetic member interacts with magnetic field |
61 |
324/257 |
Moving coil magnetometer |
18 |
324/247 |
Nonparallel plural magnetic sensors |
225 |
324/244.1 |
Optical |
266 |
324/245 |
Plural sensor axis misalignment correction |
43 |
324/253 |
Saturable core magnetometers |
197 |
324/255 |
Peak voltage type |
22 |
324/254 |
Second harmonic type |
31 |
324/252 |
Semiconductor type solid-state or magnetoresistive magnetometers |
1025 |
324/248 |
Superconductive magnetometers |
394 |
324/249 |
Thin film magnetometers |
203 |
324/246 |
With means to align field sensor with magnetic field sensed |
43 |
324/206 |
Movable random length material measurement |
33 |
324/205 |
Permanent magnet testing |
35 |
324/227 |
Plural tests |
184 |
324/217 |
Railroad rail flaw testing |
14 |
324/218 |
Rail joint cutout |
6 |
324/209 |
Stress in material measurement |
214 |
324/201 |
Susceptibility |
47 |
324/225 |
With compensation for test variable |
523 |
324/228 |
With means to create magnetic field to test material |
425 |
324/234 |
Electrically energized nonforce type sensor |
161 |
324/238 |
Material flaw testing |
300 |
324/235 |
Noncoil type |
241 |
324/236 |
Oscillator type |
269 |
324/237 |
Material flaw testing |
88 |
324/239 |
Induced voltage-type sensor |
406 |
324/240 |
Material flaw testing |
417 |
324/241 |
Opposed induced voltage sensors |
67 |
324/242 |
Plural sensors |
274 |
324/243 |
Plural sensors |
219 |
324/232 |
Plural magnetic fields in material |
315 |
324/229 |
Thickness measuring |
189 |
324/230 |
Layer or layered material |
196 |
324/231 |
With backing member |
34 |
324/233 |
With phase sensitive element |
262 |
324/224 |
With temperature control of material or element of test circuit |
79 |
324/76.11 |
Measuring, testing, or sensing electricity, per se |
578 |
324/76.12 |
Analysis of complex waves |
214 |
324/76.13 |
Amplitude distribution |
112 |
324/76.14 |
Radiometer (e.g., microwave, etc.) |
60 |
324/76.16 |
With counter |
43 |
324/76.17 |
With integrator |
38 |
324/76.15 |
With sampler |
120 |
324/76.18 |
With slope detector |
10 |
324/76.19 |
Frequency spectrum analyzer |
322 |
324/76.21 |
By fourier analysis |
150 |
324/77.11 |
Nonscanning |
67 |
324/76.33 |
Correlation |
68 |
324/76.34 |
With space discharge device |
2 |
324/76.28 |
Digital filter |
51 |
324/76.35 |
With delay line |
85 |
324/76.29 |
With filtering |
104 |
324/76.31 |
Parallel filters |
67 |
324/76.32 |
With space discharge device |
1 |
324/76.36 |
With optics |
75 |
324/76.37 |
Bragg cell |
32 |
324/76.22 |
Real-time spectrum analyzer |
99 |
324/76.26 |
Scanning-panoramic receiver |
52 |
324/76.27 |
With particular sweep circuit |
56 |
324/76.23 |
With mixer |
136 |
324/76.24 |
With sampler |
157 |
324/76.25 |
With slope detector |
14 |
324/76.38 |
With sampler |
52 |
324/98 |
Balancing (e.g., known/unknown voltage comparison, bridge, rebalancing) |
40 |
324/99R |
Automatic |
49 |
324/99D |
Digital voltmeters |
204 |
324/100 |
With recording |
12 |
324/156 |
Casings |
177 |
324/121R |
Cathode ray (e.g., magic eye) |
310 |
324/121E |
Magic eye indicators |
1 |
324/157 |
Combined |
116 |
324/103R |
Demand, excess, maximum or minimum (e.g., separate meters for positive and negative power, peak voltmeter) |
166 |
324/103P |
Peak voltmeters |
146 |
324/104 |
Thermal (e.g., actuation) |
25 |
324/150 |
Eccentrically pivoted coil |
20 |
324/137 |
Eddy current rotor (e.g., a.c. integrating wattmeter) |
40 |
324/138 |
With phase adjustment |
8 |
324/109 |
Electrostatic attraction or piezoelectric |
72 |
324/92 |
Fluid (e.g., thermal expansion) |
13 |
324/93 |
Conductive field (e.g., mercury) |
5 |
324/94 |
Electrolytic |
36 |
324/76.39 |
Frequency of cyclic current or voltage (e.g., cyclic counting etc.) |
200 |
324/76.52 |
By phase comparison |
116 |
324/76.69 |
Current output proportional to frequency |
18 |
324/76.74 |
Deviation measurement |
53 |
324/76.55 |
Digital output |
190 |
324/76.62 |
With counter |
119 |
324/76.64 |
Plural |
10 |
324/76.63 |
Using register |
17 |
324/76.61 |
With memory |
31 |
324/76.56 |
With microwave frequency detection |
22 |
324/76.59 |
With multiplexing |
33 |
324/76.58 |
With sampler |
46 |
324/76.65 |
With space discharge device |
5 |
324/76.57 |
With tone detection |
27 |
324/76.71 |
Nulling circuit |
5 |
324/76.72 |
Qualitative output |
18 |
324/76.66 |
With capacitive energy storage |
23 |
324/76.67 |
With space discharge device |
5 |
324/76.54 |
With delay line |
94 |
324/76.68 |
With filtering |
74 |
324/76.53 |
With phase lock |
119 |
324/76.73 |
With saturable device |
4 |
324/76.51 |
By tuning (e.g., to resonance,etc.) |
28 |
324/76.41 |
Frequency comparison, (e.g., heterodyne, etc.) |
135 |
324/76.47 |
Digital output |
189 |
324/76.48 |
With counter |
146 |
324/76.44 |
With filtering |
89 |
324/76.45 |
Bandpass |
40 |
324/76.46 |
Plural |
13 |
324/76.43 |
With plural mixers |
38 |
324/76.42 |
With sampler |
71 |
324/76.75 |
Having inductive sensing |
13 |
324/76.49 |
Tuned mechanical resonator (e.g., reed, piezocrystal, etc.) |
40 |
324/76.76 |
With space discharge device |
4 |
324/122 |
Gaseous discharge (e.g., spark gap voltmeter) |
70 |
324/125 |
Inertia control, instrument damping and vibration damping |
33 |
324/117R |
Magnetic saturation (e.g., in field or in amplifier) |
654 |
324/117H |
Hall effect |
388 |
324/110 |
Meter protection or fraud combatting |
204 |
324/118 |
Modulator/demodulator |
59 |
324/139 |
Motor-driven, time-controlled or oscillating (e.g., ratchet) |
5 |
324/101 |
Non-rebalancing bridge |
2 |
324/132 |
Nonlinear (e.g., thyrite) |
109 |
324/133 |
Nonquantitative (e.g., hot-line indicator, polarity tester) |
527 |
324/76.77 |
Phase comparison (e.g., between cyclic pulse voltage and sinusoidal current, etc.) |
267 |
324/76.83 |
Analog output |
38 |
324/76.82 |
Digital output |
211 |
324/90 |
Electrodynamometer instrument |
1 |
324/76.79 |
Feedback control, electrical |
61 |
324/76.81 |
Feedback control, mechanical |
7 |
324/86 |
Polyphase (e.g., phase angle, phase rotation or sequence) |
94 |
324/76.78 |
Quadrature sensing |
47 |
324/91 |
Synchroscope type |
3 |
324/85 |
With frequency conversion |
23 |
324/87 |
With nonlinear device (e.g., saturable reactor, rectifier), discharge device (e.g., gas tube) or lamp |
6 |
324/88 |
Cathode ray |
22 |
324/89 |
Space discharge control means (e.g., grid) |
1 |
324/84 |
With waveguide (e.g., coaxial cable) |
18 |
324/143 |
Plural active motor elements (e.g., for two crossed pointers) |
47 |
324/140R |
Plural inputs (e.g., summation, ratio) |
92 |
324/140D |
Ratio |
37 |
324/141 |
Voltamperes (real or reactive) |
101 |
324/142 |
Watts |
659 |
324/114 |
Plural meters (e.g., plural movements in one case) |
75 |
324/115 |
Plural ranges, scales or registration rates |
368 |
324/116 |
With register (e.g., discount type, demand penalty) |
80 |
324/129 |
Polepiece (e.g., split) admits nonunitary input conductor |
11 |
324/107 |
Polyphase |
150 |
324/108 |
Positive, negative or zero sequence |
28 |
324/113 |
Recording |
72 |
324/130 |
Self-calibration |
186 |
324/131 |
Suppressed zero |
14 |
324/105 |
Thermal (e.g., compensation) |
79 |
324/106 |
Actuation |
72 |
324/102 |
Transient or portion of cyclic |
125 |
324/96 |
Using radiant energy |
778 |
324/97 |
Light beam type (e.g., mirror galvanometer, parallax-free scale) |
36 |
324/123R |
With amplifier or space discharge device |
128 |
324/123C |
Feedback amplifiers |
52 |
324/124 |
Inverted amplifier |
16 |
324/134 |
With commutator or reversing or pulsating switch (e.g., d.c. watt-hour meter) |
11 |
324/135 |
Oscillating |
2 |
324/126 |
With coupling means (e.g., attenuator, shunt) |
439 |
324/128 |
Selective filter |
23 |
324/127 |
Transformer (e.g., split core admits conductor carrying unknown current) |
733 |
324/144 |
With electromagnetic field (e.g., dynamometer) |
40 |
324/147 |
Soft iron vane |
8 |
324/145 |
Solenoid plunger type |
9 |
324/146 |
With permanent magnet (e.g., field, vane) |
81 |
324/151R |
With permanent magnet |
20 |
324/152 |
Drag magnet |
10 |
324/151A |
Permanent magnet core |
19 |
324/149 |
With probe, prod or terminals |
191 |
324/119 |
With rectifier (e.g., a.c. to d.c.) |
119 |
324/153 |
With register |
4 |
324/136 |
With rolling wheel or ball (e.g., transmission, integrating) |
2 |
324/154R |
With rotor (e.g., filar suspension, zero set, balancing) |
42 |
324/154PB |
Pointer and bearing details |
27 |
324/155 |
With pivot (e.g., internal friction compensation, anticreep) |
13 |
324/111 |
With storage means for voltage or current (e.g., condenser banks) |
85 |
324/112 |
Tape, sheet (e.g., disk) or wire (e.g., magnetic) storage |
9 |
324/120 |
With voltage or current conversion (e.g., d.c. to a.c., 60 to 1000) |
99 |
324/95 |
With waveguide or long line |
262 |
324/158.1 |
Miscellaneous |
3073 |
324/323 |
Of geophysical surface or subsurface in situ |
198 |
324/330 |
By aerial survey |
61 |
324/331 |
For magnetic field detection |
46 |
324/345 |
By magnetic means |
182 |
324/346 |
Within a borehole |
154 |
324/326 |
For small object detection or location |
567 |
324/329 |
Using movable transmitter and receiver |
277 |
324/327 |
Using oscillator coupled search head |
75 |
324/328 |
Of the beat frequency type |
26 |
324/324 |
Including borehole fluid investigation |
77 |
324/325 |
To determine fluid entry |
14 |
324/347 |
Using electrode arrays, circuits, structure, or supports |
178 |
324/354 |
Coupled to artificial current source |
35 |
324/357 |
Including separate pickup of generated fields or potentials |
102 |
324/363 |
By varying the path of current flow |
10 |
324/364 |
Using frequency variation |
8 |
324/366 |
For well logging |
113 |
324/372 |
Between spaced boreholes |
12 |
324/368 |
Cased borehole |
72 |
324/367 |
Using a pad member |
68 |
324/373 |
Using current focussing means |
45 |
324/374 |
Including a pad member |
37 |
324/375 |
Including plural current focussing arrays |
38 |
324/371 |
Using plural fields |
24 |
324/370 |
Using surface current electrodes |
21 |
324/369 |
While drilling |
82 |
324/365 |
Offshore |
111 |
324/360 |
Using a pulse-type current source |
13 |
324/362 |
To measure induced polarization |
25 |
324/361 |
With mechanical current reversing means |
3 |
324/359 |
With nonelectrode pickup means |
19 |
324/358 |
With three electrodes |
15 |
324/355 |
Within a borehole |
72 |
324/356 |
While drilling |
35 |
324/348 |
For detecting naturally occurring fields, currents, or potentials |
75 |
324/349 |
Of the telluric type |
13 |
324/350 |
Including magneto-telluric type |
45 |
324/351 |
Within a borehole |
53 |
324/352 |
Combined with artificial source measurement |
2 |
324/353 |
With fluid movement or pressure variation |
24 |
324/344 |
With radiant energy or nonconductive-type receiver |
74 |
324/332 |
With radiant energy or nonconductive-type transmitter |
48 |
324/334 |
With separate pickup |
162 |
324/335 |
Employing multiple frequencies |
68 |
324/337 |
To detect return wave signals |
144 |
324/336 |
To detect transient signals |
40 |
324/338 |
Within a borehole |
422 |
324/339 |
By induction logging |
384 |
324/341 |
To measure dielectric constant |
59 |
324/340 |
To measure susceptibility |
9 |
324/342 |
Using a toroidal coil |
32 |
324/343 |
Using angularly spaced coils |
79 |
324/333 |
Within a borehole |
98 |
324/376 |
Of subsurface core sample |
60 |
324/377 |
For magnetic properties |
14 |
324/300 |
Particle precession resonance |
658 |
324/306 |
Determine fluid flow rate |
519 |
324/318 |
Spectrometer components |
3248 |
324/322 |
Electronic circuit elements |
1533 |
324/319 |
Polarizing field magnet |
650 |
324/320 |
With homogeneity control |
510 |
324/321 |
Sample holder structure |
313 |
324/301 |
Using a magnetometer |
116 |
324/302 |
To determine direction |
31 |
324/307 |
Using a nuclear resonance spectrometer system |
2605 |
324/310 |
By scanning sample frequency spectrum |
94 |
324/312 |
By spectrum storage and analysis |
335 |
324/308 |
Including a test sample and control sample |
112 |
324/313 |
Including polarizing magnetic field/radio frequency tuning |
114 |
324/309 |
To obtain localized resonance within a sample |
3412 |
324/314 |
With conditioning of transmitter signal |
257 |
324/315 |
With sample resonant frequency and temperature interdependence |
104 |
324/311 |
With signal decoupling |
99 |
324/316 |
Using an electron resonance spectrometer system |
147 |
324/317 |
Including a test sample and control sample |
33 |
324/304 |
Using optical pumping or sensing device |
100 |
324/305 |
Having particular optical cell structure |
28 |
324/303 |
Using well logging device |
524 |
324/73.1 |
Plural, automatically sequential tests |
1078 |
324/74 |
Testing and calibrating electric meters (e.g., watt-hour meters) |
205 |
324/75 |
By stroboscopic means |
3 |
324/72 |
Testing potential in specific environment (e.g., lightning stroke) |
456 |
324/72.5 |
Voltage probe |
772 |
324/459 |
Using ionization effects |
113 |
324/464 |
For analysis of gas, vapor, or particles of matter |
309 |
324/466 |
Using a filter |
18 |
324/469 |
Using a radioactive substance |
23 |
324/465 |
Using electronegative gas sensor |
25 |
324/467 |
Using test material desorption |
3 |
324/468 |
Using thermal ionization |
58 |
324/470 |
Using thermionic emission |
16 |
324/460 |
For monitoring pressure |
93 |
324/463 |
Using a magnetic field |
23 |
324/461 |
Using a radioactive substance |
4 |
324/462 |
Using thermionic emissions |
29 |