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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What's the most economical way to digitally measure 240V mains voltage, current and power factor?
I'm looking to capture and analyse measurements of the mains energy that I use per circuit.
I've found a few consumer products that offer powerpoint energy monitoring such as the Kill-A-Watt, but PC ...
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Help learning from a mistake connecting an oscilloscope
I have built this circuit to dim a lamp with a PWM signal. It had an issue where the MOSFET was getting really hot. So I wanted to know what was happening on the gate of the MOSFET.
I turned the PWM ...
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How do I measure differential signals (like RS-485 or DMX) on an oscilloscope?
I've encountered differential signals in a few places, such as a differential output audio amplifier and now in a project working with DMX which is similar to RS-485. (Here's a similar question about ...
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Level of a water tank with a microcontroller
How do i measure the level of a water tank with a microcontroller?
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What are the differences between a x1 and a x10 oscilloscope probe
I've heard pros of x10 oscilloscope probes a lot.
Now I need to know the cons, but I couldn't find a clear explanation.
Some people say x1 probe is for small signal.
How do you decide either x10 or x1?...
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Measuring ferrite core parameters
I have large amounts of inductors and transformers from power supplies or other undocumented sources. They are of course completely unmarked and I have no idea what kind of ferrite material they are ...
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What is the noise level as read on my oscilloscope?
The above is what I'm seeing on my oscilloscope. It's zener diode noise. Scope's set for 0.5V/div vertically, and 1ms/div horizontally. The oscilloscope has a 20MHz bandwidth, but the noise doesn't ...
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How to measure capacitance without LC meter?
I would like to use capacitors salvaged from old electronics, but I currently don't have an LC meter.
What would be some really simple circuits, that would convert capacitance to something I can ...
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How to measure supply currents ranging from 1μA to 10mA?
I’m building a battery powered data logger with a microcontroller and several sensors. I’d like to measure the supply current of individual parts with idle currents in the μA range and peak currents ...
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How does 3-wire RTD or resistance measurement works in bridge of wheatstone?
I cannot understand how 3-wire measurement will improve the resistance measurement.
They say that IF lead resistance \$ R_L \$ is the same, it will compensate. How can this happen?
If bridge is ...
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Measuring frequency of a signal above 5V with a microcontroller
I want to measure the frequency (up to 300 Hz) of a rectangle signal, that varies between 0V and Vtop, where Vtop is anything between 5V and 15V. Because I cannot apply more than 5V to the ...
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How does autoranging work in a multimeter? What is the circuit?
I was curious how this is done. It seems you would have to vary the voltage and current to measure resistance from 1ohm to 10Mohm.
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Understanding capacitance in oscilloscope probe tip
I am trying to understand the capacitance and resistance in oscilloscope probe tip.
In the above attached image, that 9Mohm resistance is used for that 1x and 10x setting that divides the input ...
user220456
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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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Water level detection, where water is somewhat polluted and has significant dissolved salts
Found this excellent QnA here which provides several options for measuring or detection water-level. For my case, it is enough to differentiate 4 levels of water (very low, low, middle, full), of the ...
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