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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Difference in noise performance between UK system and US installation
We have a piece of high-gain measurement equipment that we tested extensively in the UK and the found to perform adequately. This is a mains powered device, with the electronics powered through a ...
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What is the accuracy of a thermocouple after calibration?
I'd like to use a thermocouple to create a general-purpose temperature probe. However, the accuracy is quite a bit lower than I want. Almost every source I look at (example) lists the accuracy of a ...
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How does this capacitance measurement op-amp circuit work?
I'm studying this scientific paper where a capacitance measurement is done with the circuit shown at page 3. For simplicity I reported it here:
A sinusoidal signal is applied at the input through a ...
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Precision Tracking filter required
I don't mind if it's a band-pass or low pass filter (although I think low-pass will give a better result). Input operating frequency range is 100Hz to 1kHz. Input amplitude will be about 1Vp-p and ...
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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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Is it necessary to implement a sensing resistor plus pre-amp with Faraday cage on a PCB if I would like to have the range about 10nA measurement?
I put a 60 kΩ sensing resistor plus low-bias current amplifier with a gain of 500 into an aluminium bag and tied it to AGND for EMI shielding. The second stage is an ADS1256 24-bit ADC. The purpose is ...
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50 Hz noise from mains plug even though it isn't connected to a power source
I am developing a front-end for a smart meter and I'm trying to measure the mains by using a power lead with the other end spliced to connect it to the front-end. I firstly powered the setup with a ...
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How to determine LS, CS, RS, and CO of a piezo transducer for simulation?
I have a 24mm piezo transducer with the marking SSE2425TAL from overseas. There are no detailed specs nor graphs to get LS, CS, RS, and CO at various frequencies (but just 25 kHz is fine).
I'd like to ...
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Electrochemical Gas Sensor Potentiostat Circuit
I guess this is more of a review request than a specific question, but I was wondering if anyone has any experience with electrochemical sensors and the required circuits for gaining accurate ...
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Does creep always occur with load cells, or is there an optimum weight capacity?
I want to make a scale which I will place under a wood stove (downdraft gasifier) to measure the amount of wood that goes into the wood stove. The amount of wood which is being measured will be ...
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Vacuum tube emission (anode current, transconductance) percentage that is considered GOOD
Russian vacuum tube datasheets almost always specifies anode current like Ia = 100 mA +/-20mA at some conditions. The same with transconductance. But western tube datasheets specifies only one ...
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How do I measure an 'industry standardised' noise given Vrms ~ oscilloscope settings?
I have an example of a noise source, but the specific device is unimportant to the fundamental aspect of this question. I'm trying to measure it's level with an industry standardised method so that I ...
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Is the quantization error and random error included in the of-range error for multimeters?
When I am looking at a datasheet for a DMM (Digital Multimeter) to calculate the accuracy of a measurement it specifies two error sources: of-range and of-value (also called of-reading). For example ...
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Error Analysis due to Voltmeter Constraints
I got a situation: at the moment I am unable to access both channels for Keithley 2182A nanovoltmeter using LabVIEW. However, for some odd reason, while I cannot access the channels at once, LabVIEW ...
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