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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Can an oscilloscope be used as an EKG?
I was at my doctor's office and noticed an EKG machine that looked like a standard oscilloscope. In fact, its case was almost identical to my dual channel Tektonix 1104b. The main difference was that ...
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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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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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Why only sine waves?
I have already read a few EE texts where a sine wave is often seen.
Why is the sine wave often used as a test function for a circuit or a system? Why don't we use any other signal instead of sine?
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Why is this meter giving different readings depending on its orientation?
My newly-restored (re-capped) 1950s vacuum tube voltmeter is now operational...but there's one further issue. The meter gives correct readings when lying on its back, but when oriented vertically- as ...
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Why do digital scopes sample signals at a higher frequency than required by the sampling theorem?
In the quest for a not so expensive PC scope/logic analyzer, I have found a nice little device it looks very well done and I know it will do the job.
However looking at the specifications, I ...
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How can I measure the temperature wirelessly inside a piece of meat?
For a cooking experiment, I'd like to be able to measure the temperature inside a piece of meat while it's being cooked. Due to the mechanics of the cooking process, it's going to be difficult to use ...
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Why are oscilloscope input impedances so low?
My question is two-fold:
Where does the input impedance come from?
I'm wondering where the input impedance of your average multimeter or oscilloscope comes from? Is it just the input impedance to ...
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How does the network card determine the cable length?
I have an older Gigabyte Technology GA-MA770T-UD3P motherboard with an on-board network card described like this:
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What kind of oscilloscopes are qualified for measuring USB 3 Super Speed Signals?
I understand that they probably will be very expensive. But I have little idea of what kind would qualify. How much bandwidth? At what sampling rate? Any other parameters?
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Physically determine unknown wire's gauge
Is there any way to easily and accurately determine the gauge of stranded wire by measuring it?
I know you can pretty easily determine the gauge of solid-core wire with just a pair of calipers by ...
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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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Ways to determine polarity (dc) without a meter
I came across this question about how to figure out the polarity of a cell phone charger without a meter. This made me think of what methods you could use to figure out the polarity other than using a ...
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How can I measure gate capacitance?
Is there an effective way to directly measure the gate capacitance of a power MOSFET, like say the IRF530N?
The way my circuit is behaving would indicate that the effective gate capacitance is ...
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How do you calculate the noise of an op-amp circuit?
I think I know how to do this, but you can find a lot of different instructions and calculators online that contradict each other. I have yet to find a clear, concise procedure for calculating the ...
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