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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Do digital multimeters work the same in vacuum?
We want to use a RS14 Handheld Digital Multimeter inside a glovebox and therefore we submit it to vacuum (0.1 bar) to come in and out of it, and to inert N2 atmosphere once it is inside the box.
Does ...
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Matching network for two-port with internally matched inputs/outputs
Background
I had a lab in school where we were given an LNA with inputs/outputs matched to 50Ω, that will be connected to a 50Ω system:
The task was to design the input and output matching networks:
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How can I describe the loading effect of an ohmmeter?
How can I describe the loading effect in an ohmmeter? I've been given an assignment with this question, and I tried to look it up on the internet but could find no other material apart from loading ...
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Tension load cell options
I'm designing something similar to an electronic hanging scale (think a heavy object on the bottom, with a scale attached immediately above it). I am not that familiar with what the most typical way ...
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Test lab noise floor variance and emission limits
I have recently taken part of noise floor measurements for emission tests from two separate EMC labs, both well known and international companies. The thing that shocked me is the dramatic difference ...
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Contactless measurement of internal time base
I'm currently trying to measure the internal time base of stopwatch (both mechanical and digital) to ascertain the expected accuracy of the device. I have looked through many articles related to the ...
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How do I calculate the minimum deflection I can sense with a strain gauge, like the BF350-3AA?
I have a strain gauge (the BF350-3AA), and I will be connecting it to an HX711-based amplifier sensor.
From its low-quality datasheet, I've pulled out the following figures:
Nominal Resistance: 350 ...
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How can I correlate a RSSI value to a distance measurement more efficiently?
I want to develop a trilateration algorithm using 3 fixed advertising beacons in different parts of a room and a mobile receiver which continuously gets the RSSI values of the 3 fixed beacons and ...
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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 ...
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Can I use 12 V and -12 V together?
I am sorry if this question is pretty easy but I am a beginner.
I have a PC PSU that provides two lines:
12 V 11A
-12 V 1.5A
If I used them together will I get 24V, and how many amps can they provide?...
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Measuring flyback SMPS feedback loop response
I'm trying to measure the feedback loop on a isolated flyback SMPS. My goal is to determine the phase margin and 0 dB cross-over frequency.
The most common circuit I have seen is the one recommended ...
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AC leakage issue with high impedance measurement setup
I am having an AC leakage current problem with my measurement setup that I typically use for lock-in measurements.
I employ a 100 M\$\Omega\$ resistor as a voltage-current converter, and in series, a ...
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Measure power & energy usage in tapped line
Here is the schematic of the circuit in question:
The horizontal lines are from the AC mains. Ammeters and wattmeters are connected at any 2 points in the main lines. I am trying to detect if the ...
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Measurement of relay characteristics so can detect before failure
I am working with a very large safety system which was designed around 30 years ago. It has a system of relays interlocked together in a logic configuration so that it will failsafe if any relay ...
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Debugging PLL STW81200TR not locking
I need a bit of debugging help with SWT81200 PLL that I am using on my custom designed PCB. I am able to configure registers through SPI communication, but the problem is that I am not able to achieve ...
