All Questions
Tagged with measurement noise
29
questions
1
vote
1
answer
315
views
HLW8032 energy meter circuit showing power usage at no load
I am designing an AC energy metering circuit. The circuit has to measure voltage, current, power, power factor and energy used for two channels (from the same source). The HLW8032 transmits 24 bytes ...
- 103
2
votes
2
answers
69
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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 ...
- 105
2
votes
1
answer
342
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Low noise virtual ground, voltage reference or LDO + op amp?
I'm doing some sensitive signal measurements in 1~10kHz range where I amplify and filter (multiple active stages) a small voltage signal by hundreds ~ thousands of times and then sample it. A negative,...
- 185
0
votes
0
answers
98
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CD4051 noise measurement
I am using a CD4051B for multiplexing 8 inputs into one according to 3 control bit A, B, C.
Below is my schematic:
My problem is :
The input of the MUX (in_mux) is quiet disturbed on my PCB board ...
- 87
2
votes
0
answers
211
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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 ...
- 95
4
votes
0
answers
90
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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 ...
- 153
1
vote
1
answer
57
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System recommendation smart citizen measuring noise and air quality [closed]
I really much like the idea of citizen science movement. After researching a couple of projects and tinkering around with Arduino (ESP8266) and Raspberry Pi I was not sure what to use. Especially the ...
- 111
2
votes
0
answers
138
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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 ...
- 7,567
1
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1
answer
74
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How can I extract the rms noise from the measurement's over all noise?
To clarify my question, here is an example: Let's say I have an opamp and I want to measure and quantify its output noise when its input is grounded. So after shorting the opamp's input to its ground, ...
- 1,468
2
votes
1
answer
257
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What is meant by the term "baseline noise" in this context?
I came across this article about oscilloscopes. Under the figures and scope screenshots there is a term called "baseline noise".
I googled but it turned out this baseline noise is used at different ...
- 1,468
1
vote
0
answers
145
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MEMS Microphone noise floor power level & audio noise spikes measurement
I have a circuit with a MEMS microphone and would like to be able to measure the audio noise spike contents and check the noise floor power level in the audio circuit.
My intention is to connect the ...
- 143
0
votes
4
answers
3k
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How do I measure very low frequency noise?
I'd like to measure low-level noise in the 1 Hz to 100 kHz range, for example at the output of a LDO. For higher frequencies a spectrum analyzer would do the job, but most only go down to the MHz ...
- 3,501
4
votes
2
answers
537
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Why is this the maximum dynamic range in a spectrum analyzer?
In Keysight's popular AN 150 there is a plot of noise and harmonics amplitudes versus the level of the input signal at the mixer (page 57).
It's stated there that the maximum n-th dynamic range is ...
- 1,028
0
votes
1
answer
465
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Mains frequency noise components
I'm currently doing a lot of work in measuring transfer functions of circuits. One thing that crops up a lot is mains frequency noise:
As you can see there is a huge 11 dB leap at 50 Hz, followed by ...
- 1,856
2
votes
1
answer
7k
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Measuring noise with an oscilloscope
What is the proper procedure to measure RMS noise with an oscilloscope?
I have 2 standard resistors, 1k and 100k and a 1.5GHz BW, 5GSa/s Keysight DSO. I have a probe which offers 1:1 (1MOhm//100pF) ...
- 1,326