Measurement is the assignment of numbers to objects or events. All measurements consist of three parts: magnitude, dimensions (units) and uncertainty.

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How do i measure the output voltage of lm35 with digital voltmeter?

I know this is a very stupid question. Lm35 has 3 pins: Vcc, Analog output voltage, Gnd. Is it ok to measure between analog output voltage and gnd? Im asking because Vcc and Gnd is a dc.
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1answer
32 views

How to measure ratings of a transformer

If I am given a transformer without any datasheet of it. Then how can I measure the maximum current and voltage rating of the transformer?
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1answer
77 views

How to measure frequency of sine wave?

How to measure frequency of sine wave using pic microcontroller? I found the article on this website http://microcontrollerslab.com/sine-wave-frequency-measurement-using-pic/ But I didn't understand ...
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3answers
96 views

Measuring the inductance of a coil?

I have a hand-wound coil I'm using in an LC Tank circuit. Using my multi-meter, I found out that the coil is drawing .6mA at 9v. Using Ohm's Law... $$R = V/I$$ $$R = 9/.0006$$ $$R = 15kΩ$$ Is there ...
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1answer
34 views

Can I measure large force using series FSR?

Is it possible to measure large force using multiple Force Sensitive Resistors in a series? Will I have to stack the resistors up? Will the measurement be reliable if I place them side by side? I ...
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2answers
94 views

ADC calibration in ATTiny88

I'm writing an embedded app for ATtiny88 - one of its task is to measure voltages of serial connected two 12 V car batteries. The microcontroller is powered from around 4.5-5 V (LM317), measured ...
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1answer
39 views

How can I make an accurate torque/RPM curfer for the random electric motors lying around my garage?

I am blessed with a garage filled to the brim with all sorts of electric motors, most of them sourced from broken household appliances and the like. I would like to gather some data about them, like ...
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1answer
46 views

If you want to test a step-up transformer, must the load resistor equal the source impedance?

Ideally, do you want to add R1 to balance out the impedance so you get an accurate reading? simulate this circuit – Schematic created using CircuitLab I'm trying to find out the turn ...
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3answers
173 views

Measuring change in inductance

I have a coil whose inductance will be changing continuously. I would like build a circuit to monitor the change in inductance continuously. Can I just use a RCL circuit and give it a sine wave of f ...
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0answers
56 views

Directional Coupling at kHz Frequencies

I want to precisely measure the forward and reverse power on a high-voltage power supply that operates from 10-100kHz, at power levels on the order of 20W. To do this, I need to make or buy a ...
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0answers
61 views

How do you correctly measure the gate voltage of a MOSFET?

If you have a half-bridge, or an H-bridge, or some other usual configuration; and you want to see the voltage you are getting on the gate, to check for any errors and shoot-through. Do you do it like ...
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2answers
40 views

measure capacity of a battery after charged

I have two AAA rechargeable batteries that claim to have 550Mha capacity. My first question is, how can I measure the Mha and make sure the battery is fully charged? Second question and related ...
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2answers
112 views

Is there a way to measure three discrete resistances simultaneously?

I'm working on a test box for fencing body cords. These cords are always 3 wires, and will plug into a box that I'm still designing. The test box I currently use connects to a multimeter and has a ...
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1answer
74 views

How is water resistance of a device measured?

This question has relation to physics as well, but since it is electronic related, it is here. I was watching a video that is testing the water resistance of Apple Watch. They say, at 3 feet the ...
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2answers
117 views

Creating a large 18650 Array

I am looking for some help with wiring for a large battery array using 18650 lithium ion batteries. Ok so I am looking at going solar and lead-acid batteries are too low overall capacity and their ...
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3answers
146 views

Current decreases while reading

I'm a bit confused about reading current on a breadboard using a multimeter (I'm a complete beginner with electronics). I'm using a self-powered breadboard which should deliver 5V / 1A. Multimeter is ...
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2answers
44 views

Circuit for measuring static charge

I want a cheap tool for investigating the source of and solutions for static electric shocks (from a vehicle). This link shows a particularly attractive solution; just a FET, LED, resistor and ...
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1answer
72 views

How does one measure the power factor?

How does one measure the power factor? $$\text{power factor}\equiv\frac{\text{power}}{|V||I|}=\frac{R}{\sqrt{R^2+(1/\omega^2C^2)}}$$ for an RC circuit driven with \$V(t)=V_0\cos{(\omega t)}\$.
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1answer
37 views

Vector Network Analyzer - The effect of increasing the number of measurement points

Does increasing the number of measurment points make the measurement time longer? RBW value does change the time, but does sweep bother the time of taking a single sample? I'm looking for ...
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1answer
34 views

Partial load failure detection circuit

I'm working on the power supply of a temperature controller which sends about 5kW of power maximum (230VAC 50Hz) into 3 sets of 12 heaters (actually, 3kW + 1kW + 1kW). I'm at the stage where I need to ...
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1answer
37 views

What's the usage of storing recorded measurements of multimeter and soldering iron station in computer?

Assume you want to purchase a multimeter for your job. some multimeters have a USB interface to store the recorded measurements in the computer and for this feature, you have to pay more money. but ...
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0answers
22 views

RIN measurement of CW laser

Right now Im doing an RIN measurement of a CW Raman fiber laser. In theory, Im supposed to see a relaxation oscillation which manifests as a single peak in the trace. What if I can't detect the ...
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2answers
63 views

Is Induction Wattmeter ,Energy Meter and Watt Hour Meter the same thing

I have a topic to study regarding Energy Meters. In the Syllabus it says Energy Meter, in the textbook it says Induction Wattmeter and one online reference by IIT, says WattHour Meter/Induction Type ...
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0answers
24 views

Does higher clock speed equate to higher resolution of distance measurement using RF?

I am trying to create a simple measurement system using RF but have found only devices that have fairly large windows of accuracy (+/- 1ft is the best one I've found yet). If I want to measure the ...
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2answers
35 views

Coil and Core-What exactly this is?

Im learning about electrical measuring instruments(PMMC).In this textbook it is said that a rectangular coil is wound on a aluminium former.Inside which there is an iron core. My question is what ...
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3answers
62 views

Which low pass frequency filter to configure to measure/calculate DC-DC converter efficiency?

I am measuring the DC-DC converter active power (P in watts) efficiency of a TI (Webench) LM3150 PCB that converts 12 to 5VDC. In the answer of question Measuring precisely the efficiency of a power ...
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3answers
191 views

How do utilities calculate transmission lines impedance?

I'm an electrical engineering student getting into Transmission Circuit Analysis, and a question came out to me: How do utilities measure their transmission lines impedance? Do they use special ...
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1answer
103 views

How to correctly use a LC meter/bridge

I have a LC meter at hand that I'd like to use it to measure the inductance (dominated by L1) of a circuit branch like this : simulate this circuit – Schematic created using CircuitLab ...
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3answers
59 views

Thickness Measurement

I would like to measure the thickness of a stack of paper without touching it. The measuring device needs to show if one sheet is removed. I do not need to know the measurement in inches. Units are ...
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2answers
98 views

How can I make the dimensioning of a temperature monitoring circuit?

I need to design a circuit to measure temperatures in the range 15-40 degrees C (this will later be the basis for a regulator of a peltier-element for a fridge). I tried a circuit using the ...
3
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2answers
129 views

Under water distance measurement

For a laboratory / field test, I'm looking for an easy solution to measure the soil surface elevation. The test runs a flow on a bed. When the erosion takes place the sediment concentration goes high ...
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1answer
80 views

Characterization of Power Harvester

I have chosen a power harvester to power a few things as part of a wireless system. This one is the one I have and it seems to be operational: http://www.powercastco.com/PDF/P2110-datasheet.pdf ...
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4answers
424 views

Is this true RMS?

This question is about obtaining a true RMS voltage reading from a running sampling ADC. Does this give me a true RMS reading, or where did I made a mistake? Construct a ring buffer of an large ...
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1answer
129 views

Measuring Output Amps From a Power Supply

I am in the quest to build a cheap bench power supply, i have successfully designed, built and tested the entire voltage circuitry. The device includes a graphic LCD screen that displays the voltage ...
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2answers
37 views

Technique to measure/infer Vf for LED given If

This isn't the normal resistor question, and I'm familiar with the theory and Which is better: using a resistor with an LED, or "precisely" matching the Vs to the given LED's Vf rating? ...
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1answer
103 views

How to measure the quality of a USB charging cable?

I have a set of USB cables (data and charge) and I noticed that, for a given charger, the charge time differs by cable. What would be a good way to measure the charging fitness of a USB cable? ...
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1answer
66 views

Abstract Datasheet Dimension Notation

I am attempting to create a footprint for a Surface Mount Component and I am using the manufacturer's datasheet for reference. They include PCB dimensions but the notation used is a bit confusing. It ...
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0answers
59 views

how work this flow meter

As you know , The principle of operation for the magnetic flow meter is based on the Faraday’s Law of Electromagnetic Induction.An electrical current (I) is applied to a coil package inside the flow ...
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52 views

How to calculate distance between two objects(robots)?

If I have two soccer robots, and want each robot knows the distance between itself and it's teammate, how can I do that? (without external supervisor camera)
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2answers
96 views

How to break out SMD chips in-circuit?

For a current project I am attempting to amplify and cross-wire the signals from the address pins of SMD RAM chips. Basically this means I am trying to break out the pins of a SMD chip, similar to how ...
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5answers
182 views

How measure the voltage over a large resistance?

I know initially this question might come across stupid and obvious but all is not as it seems. I want to measure the voltage drop over a 10M ohm resistor but my voltmeter's probes have an ...
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0answers
45 views

IR temperature Sensor reading ambient temperature in a room

I bought a product that has a IR temperature sensor and I want to receive a "good quality" ambient reading of a room. I have an idea how to use the IR sensor for the ambient, even though it would be ...
0
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3answers
182 views

How to measure nano-amps easily?

I want to measure the stand-by current of the PIC, but my DVM has minimum 2000micro (u) amper switch. It shows 0 micro amps when in 2000 u amps mode. Without building circuit a complex (more than 3-4 ...
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1answer
84 views

Anyone may suggest a temperature sensor technology that will work to a max of 200ºC?

Cheapest sensor technology as possible, up to +- 5ºC or 5% of accuracy. Better if it doesn't need complex (and costly) additional circuits.
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1answer
47 views

Uncertainity Calculation

> How can i calculate the absolute uncertainty dt in the following case T=(P/A)^1/4 if ...
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2answers
137 views

Big capacitors measurement(LCR meter related)

I digged up some capacitors from amplifier and decided to test them, one of them is said to be 8200 uF, the other 4700 uF. I measured them with LCR meter and it gives very strange numbers. If LCR ...
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2answers
115 views

Full wave AC Voltmeter Vs True Rms Voltmeter

Does a full-wave rectification AC Voltmeter give the same indication as a true rms voltmeter when you measure a 50 Hz sine wave?what happens if the the sine wave is clipped by an inadequate ...
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1answer
106 views

Is using a transformer at reduced voltage a bad idea?

My Google is failing me. I want to make an isolated AC voltmeter capable of working at 120 or 240 VAC. I've found a suitable 240 volt to 5 volt transformer to use (current capacity doesn't matter - ...
3
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1answer
92 views

Power supply noise measurements

Im working on a project where I need characterise the noise from a power supply so I can then design some filters. The power supply provides 5V, 12V and -12V to a set of analogue sensors (hence the ...
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2answers
177 views

Oscilloscope measuring of PMT in photon counting mode

I have a setup as drawn below: DC source of 15V connected to high voltage (HV) source of 1500V connected to photomultiplier tube Hamamatsu, R1-R3 are resistors builtin the socket of PMT (there are ...