Questions tagged [measurement]
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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Criteria to see if a battery was over-discharged in the case of Li-ion cells and NiMH batteries
Consider a Li-ion pouch battery from an RC model. Is there any reliable way to determine by measurement if the battery was in a over-discharged state in the past. (In particular I am looking for ...
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Connecting LVDS to oscilloscope using ferrite bead to isolate GND/SHIELD
I want to measure LVDS signals with a scope.
Will my solution work? (Shown at bottom.)
I know of other ways of doing this, but I am hoping this way is cleaner and easier.
Specs:
Frequency:~100MHz
...
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S11108 Circuit Design Logic
This is my first post and also my first dip into electrical engineering, and I wanted to ask if you have any suggestions on the circuit I have designed. As a background, I'm a Computer Science student,...
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Using a DAC to measure system gain
I am using a Wheatstone load gauge through an AD8295 op-amp to a SAMD21 uC ADC. The op-amp uses a resistor to set gain. An analog switch is used to change gain. Since the resistors are not exact (G = ...
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How to eliminate internal circuit current consumption from the measurement in bi-directional current measurement circuit?
I am comparatively new in this domain. I am trying to design a bi-directional current measurement circuit. This is a 5V to 9V DC system. I have two USB C female ports at both ends. Which means I can ...
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Can I measure pinholes in a dielectric layer using LCR meter?
I have a thin dielectric film (~1 um) and I want to measure the quality of the film in terms of not allowing leakage current through pinholes. Can I use an LCR meter for this purpose? If yes, how? If ...
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How do you characterize the noise in a fluid velocity measurement device?
I have designed and built a measurement device that detects the velocity of a fluid flow (a constant-temperature anemometer). I wanted to experimentally characterize the noise performance of the ...
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Optical distance measurement idea [closed]
Ok, so I posted this using my phone some time ago, more than a year ago. However let's just take it from the top, integrating the criticisms that I remember.
I am a cnc machinist by trade and we ...
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Questions about connecting ADS1115 for voltage measurement
Purpose: to measure the voltage on the DC bus (about 600VDC).
ADS1115 Datasheet
I looked at the use cases and saw two connection options (in the first case, we use two inputs, in the second, only one)....
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Sigma-delta modulator (ADC), can it be used without sinc3 filter?
Purpose: isolated measurement of DC voltage (about 600V).
For these purposes, I found two options:
ADS1115 (I2C ADC) + I2C digital isolator
CA-IS1204 Isolated Sigma-Delta modulator
I am considering ...
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74LS283 4-Bit Adder doesn't work as I expected. It sets some inputs to high voltage
I bought a few cheap 74LS283 chips. They don't work as I expected.
For some reason it sets the A1 pin to high voltage (5V) at all times. Considering the A1 and B1 pins are supposed to be input pins, ...
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Generating Double pulse using Tektronics Function generator AFG31000
I have Tektronics AFG 31000 function genertor with built in double pulse test app. I want to generate two pulses for my double pulse test but this so simple task is becoming a mountain to climb for me....
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Why can't capacitors on PCBs be measured with a multimeter?
While looking at this article, it mentioned that one cannot test the capacitance of a capacitor while it is on a PCB. The explanation given is:
The reason is, that when a capacitor is inside the ...
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Current measurement in every 20ms
I want to measure the current in every 20 ms and record the measurement. I was using the Fluke DMM and in that I am not able to measure something less than 125 ms. Could someone suggest any methods ...
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measuring frequency with opto-isolator
I have a circuit where 220VAC mains is stepped down by transformer to 48V and through an 5k1 resistor I'm activating optocoupler that drives a LED through a resistor on the other side. I am measuring ...
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