Questions tagged [calibration]
Correlate the readings of an instrument, sensor, etc. with those of a standard in order to check its accuracy. Adjust experimental results to take external factors into account or to allow comparison with other data.
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How to calibrate a NTC Thermistor using a manipulated Steinhart-Hart Equation?
I have a NTC Thermistor setup in a voltage divider to with a Arduino such that it can read me the temperature using the Steinhart-Hart equation.
I initially calibrated the thermistor and measured its ...
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How to calibrate a compass module that isn't producing elliptical data?
My company is working on something similar to (but not the same as, but it's just easier to explain it like this) an electronic prize wheel, mounted horizontally.
The method of detecting which prize ...
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RP2040 ADC calibration (schematic)
I was working with Raspberry Pi Pico ADC pins, and found out there are minor errors in the Pico ADC (12bit) values:
When the ADC pin is connected to ADV_VREF, the ...
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Changing output impedance of a logic gate to 50 ohm
I making a simple circuit to take 10 MHz output from a GPS module and calibrate a frequency counter with this 10 MHz signal. I have already found a circuit designed by radio amateur ZL2PD. Circuit ...
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UNI-T UT181A question: what is confidence interval used in the datasheet?
So the question is: https://www.batronix.com/pdf/uni-t/UT181A-Manual-English.pdf
The manual has
So if you are measuring perfect 50 Hz source you have resolution 0.001 Hz the values are in interval ...
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When I hold a stepper motor while it is operating, what happens? Does it draw more current or maybe reverse current?
I was wondering how stepper motors of 3D printers work and I found that some of them does not have a calibrating mechanism like a switch or whatsoever. It seems like there is an internal thing that is ...
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MCP39F511A Response Contains Unexpected Data Before Correct Packet reading calibration registers
I'm currently working with the MCP39F511A power monitoring IC and encountering an issue with the serial communication responses I'm receiving. Following the device's manual, I send a packet to request ...
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How do you de-embed a shorted 2-port fixture?
I've been working through reproducing Steve Sandler's 2-port shunt-through measurements (2019 SIJ article, Picotest slide-deck). My target is to measure capacitors with ESR down to 1 mΩ with an ...
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External DAC (DAC8568) software calibration
I'm using a 16-bit 8-channel DAC (DAC8568), driven by STM32 MCU.
I need to obtain the 0-5V and 0-10V switchable output range, so to achieve that the voltage must be amplified with op-amp.
This raises ...
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What is the best and simplest way to generate multiple accurate reference voltages?
I need several reference DC voltages to use them to calibrate hundreds of circuit boards manufactured in our facility.
The voltages to be calibrated are
5V
10V
100V
200V
500V
The accuracy required ...
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Calibration of the Atmel M90E32AS Energy Metering IC
I'm working on an energy metering project featuring the Atmel M90E32AS, connected with an ESP32-S3.
From the Application Notes of the IC, I understand that it needs to be calibrated first. However, I'...
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Do factory calibrated electronic compasses need to be re-calibrated in the field?
I have been working on an electronic compass. It has become apparent the best way to calibrate the magnetometer is once out in the open with out any large metal object nearby.
Curiously, what I have ...
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Determining Sensor Calibration Method
How to calibrate a sensor that can be affected by humidity? For example MQ-135 as gas sensor (NOx, CO, etc.). According to the datasheet, there are two different curves for the sensor response when ...
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Force Sensitive Resistor Calibration
I have been trying to calibrate FSR06CE Force Sensitive Resistor.
Data sheet here.
For starters I started by placing deadweights on the top of the FSR's active area and using a multimeter and DSO I ...
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Can you calibrate your VNA to show matching circuit behavior, without the antenna connected?
We need to make a matching circuit for an antenna, but the antenna feed point is in an inconvenient location.
Is there a way to calibrate the VNA at the feed point such that the VNA will show the ...
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Need Help Calibrating Force Sensing Resistor (FSR)
I'm currently working on a project that involves using a Force Sensing Resistor (FSR). However, I've run into a bit of a roadblock when it comes to calibrating the FSR. I don't have access to a weight ...
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Why single pass measurement with non_constant input voltage is not acceptable in LISN insertion loss calibration
In my provious quesiton How to understand the "zero source impedance" in LISN insertion loss calibration, Tim Williams gave my a clear and wonderful answer. But I still have a question.
I ...
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How to understand the "zero source impedance" in LISN insertion loss calibration
Figure 1: 50 uH LISN Diagram
Figure 2: Input impedance of the LISN varies with frequency from 5Ω at 9 kHz to 50Ω at 30 MHz
In Page 27 of Calibration and use of artificial mains networks and absorbed ...
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What happens during instrument calibration? [closed]
I've worked with a lot of instrumentation for both non-electrical phenomena (UV-vis spectrophotometer measuring DNA concentration, MEMS gyroscopes) and electrical ones (the usual oscilloscope, ...
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Calibrating a high current shunt resistor
In a circuit I'm developing I have a shunt that is used for current measurement of +/- 80A. How can its calibration be done? Suppose our budget for this can be 1000 to 1500 USD, what would be the best ...
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Simple calibration of probe [closed]
Usually I will calibrate passive oscilloscope probes under the scope setting with "Start Attenuation/Offset Calibration" and "Start Skew Calibration". The last step is to ensure ...
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Why does bathroom scales use half bridge load cell rather than 4 full bridge loadcell in parallel? Except for the price, is there any other reasons?
I have been wondering why does bathroom scale uses 4 half bridge loadcell connected like this figure bellow rather than using 4 full bridge loadcell connected in parallel? Except for cheaper ...
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Calibrating the R&S FPL 1003 Spectrum Analyzer
I am setting up an EMC test bench and I have a spectrum analyzer(SA): The Rohde and Schwarz FPL 1003 Spectrum Analyzer. I am trying to conduct some preliminary tests to ensure that the results seen on ...
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Rotated gyroscope 180 degrees but integration shows 90
I'm a student new to sensors. I'm currently calibrating the gyroscope from the following IMU: ICM42670. I was able to get the bias by leaving the gyro for some time and getting the average of the ...
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When calibrating a VNA, does the feedline length matter?
We need to measure an antenna feedpoint (to record an .S1P file) that is far away from the VNA. We can calibrate the VNA to the feedline that will ultimately be attached to the antenna before it goes ...
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ADXL345 accelerometer: strange values
I have an ADXL345 digital accelerometer by Analog Devices, and I am using it with an STM32F103. The problem I have been dealing with for a long time is that it gives strange values. In addition, I ...
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Understanding TRM calibration in network analyzers
I am trying to figure out how TRM calibration in network analyzers works. I have read a couple papers about it, but didn't understand it properly, therefore I tried to develop it myself. I do this by ...
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The meaning between raw and calibrated S parameters
VNA: E5071C
Cal kit: 85033E
DUT: cable end bandpass filter
This figure shows measuring S21 of filter:
Upper figure shows real part of S21 and lower one shows imaginary part of S21.
Blue line is raw ...
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Temperature probe calibration
How would you design a replaceable temperature sensor probe such that end users do not have to send the entire unit (processor plus probe) away to be re-calibrated? So that you could just send them a ...
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Will this Battery Voltage Monitor with on-the-fly calibration work?
I am trying to make a voltage monitor for my RV battery as the one included with the RV is not very accurate. I would like the result to be accurate to +/-0.01V and intend to use an ESP32 and ...
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ADC CS5532: "digital gain scaling" - ADC Calibration without full scale signal
I'm making a digital weight scale with Arduino and CS5532.
My problem is to calibrate adc with the offset signal and a known weight signal that is not full scale point.
The CS5532 allows me to ...
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When should an unmatched antenna be measured with a cable length in even multiples of a half-wavelength?
A few years ago someone told me that if you use a cable which has a length of an even half-wavelength multiple for the frequency being tested, then the impedance measured at the end of that cable will ...
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Can a BNC through-load be used as the load to SOL-calibrate a VNA?
Related to this question, I'm having a hard time finding a female 50-ohm load to calibrate a reference plane at the end of a male BNC feedline. However, feed-through loads are readily available.
Is ...
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Is there anything particularly special about a "short" and an "open" in a VNA calibration kit?
I would like to calibrate a VNA with the reference plane at the end of a male BNC feedline. Surprisingly, female SOL kits are hard to find. There are many BNC 50-ohm loads available but I'm having ...
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How to calibrate piezoelectric sensor using charge amplifier
I have a pressure sensor kistler 6051B1, which is 6 pC / bar.
I’m trying to calibrate the sensor in order to use. I have a charge amplifier to read the output, but I honestly have no idea even how to ...
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How to solve this calibration problem of National Instruments Elvis board?
I have NI Elvis II board and i am trying to calibrate my ELVIS II using the self calibrate option of MAX(measurement & automation explorer). I have tried my best to follow the instructions given ...
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Does an RTD simulator require calibration?
Does an RTD simulator need calibration or not? Basically, I can measure that the value of RTD with a calibrated multimeter and I can show the difference between multimeter and RTD simulator. So, can ...
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How to interpret linear equation of IMU output for sensor calibration
I created a system to measure angle in between two IMUs in 1-axis by getting the difference between their rolls. I then applied a kalman filter that takes into consideration the roll angle and ...
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Measuring capacitance of two wires [closed]
I have made a capacitor as follows:
I cut two straight wires of diameter 0.52 mm and length of 29 cm and separation width of s=2.5 cm.
I stuck them on a piece of neon to keep them fixed.
Here is the ...
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Is AC current clamp meter accuracy affected by the inner wire curving around the outside?
I have a SCT013-030 current clamp sensor I plan to use to read out the power usage of a mains AC load. It works by wrapping around one of the AC strands of wire to measure the magnetic field.
The one ...
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Two DPS310 sensors coded same but different values. Why?
I have two DPS310 sensors. My aim is to find the altitude value from these sensors. Both sensors give different altitude values.
I have checked the calibration coefficients. Two are similar, but have ...
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How do I calculate accuracy marked as ±(4 ppm rdg + 10Digit)?
Trying to figure out the correct way to calculate accuracy with LSD. I looked at a few sources, but I'm still confused on the topic.
The question:
A digital voltmeter can display counts up to 1999999 ...
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Can calibration break PSUs?
I was tasked with rounding up all of my company's measurement devices (calipers, power supplies, scales, etc.) and arranging a visit from a calibration services company. The company came and ...
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How does accelerometer calibration work?
Inside a MEMS accelerometer there are some miniature spring-mass structures that displace under gravity or external force (acceleration). These forces are proportional to or can be indirectly ...
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Does NTC temperature measurement need calibration?
I'm creating some temperature sensors for home use. To measure outside and rooms' temperatures.
Range from -30 °C to +50 °C.
Temperature measurement is based on 10k NTCs SDNT2012X103F3950FTF (B=3950K, ...
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MAX6675 k-type thermocouple ADC is giving high readings
I have designed and built a small fairly simple circuit that uses a MAX6675 chip to take temperature readings from a multiplexed array of 16 k-type thermocouples.
Datasheets:
MAX6675: https://www....
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Calibrating 500 kg load cell with an ESP32 and HX711 without putting actual 500 kg on it. 3 V excitation
Edit and update !
Considering the following data sheet ( calibration data from factory) what is the correct math to calculate the weight?
500 Kg = Excitation * rated output. ?
Or
Weight = 41.01 * ...
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When and why does embedded Electronic Control Unit (ECU) use default calibration values? [closed]
Typical embedded ECU stores real calibration values and default calibration values in Non-Volatile Memory (NVM).
Let's say ECU is Steering Controller and its primary function is Lane Keep Assist (LKA)....
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Did I calculate my force sensor resolution correctly?
I am trying to calculate the resolution of my simple force sensor system in Newton [N].
The sensor system consists of a simple voltage divider, where the voltage across the FSR is measured by an 8-bit ...
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How do I find the accuracy / uncertainty of my force sensor system?
I have built a force sensor using an arduino and a self built force sensitive resistor (FSR.) The sensor system consists of a simple voltage divider, where the voltage across the FSR is measured by an ...