Questions tagged [sensor]
Sensors convert a physical quantity (e.g. temperature, pressure) into an electrical signal.
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Practical question: Temperature sensitive device, insulating or add more thermal mass?
If I have a very sensitive photodiode/sensor/analog front end part of a circuit that can be sensitive to temperature and the device does not draw much power (for example, a small photodiode,) what is ...
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SHT31 temperature and humidity sensor stops responding without error
I will first tell you how I tried two different SHT31 sensors with the following configuration and then I will tell you my experiences.
My Setup: Arduino Pro Mini with SH1106 OLED display + SGP30 TVOC ...
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Altitude sensor for Raspberry Pi using only GPIO [closed]
I'm trying to get altitude data for a Raspberry Pi. I also need it to use only regular GPIO, and be relativity small.
I was thinking about an MLP311A5 with some sort of analog to PWM converter, but in ...
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What is the best sensor to use in a wearable device to monitor body temperature on a continuous basis [closed]
I am making a device for monitoring of Temperature of Cows , I want to know does DS18b20 monitor body temperature of cows , or i need to find another sensor
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Touch sensitive arcade
I'm 3D printing a series of motorised automata. I want to display these like an arcade in my window that fronts the street.
To make them interactive I want anyone interested to be able to switch the ...
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Difference between compass/magnetic sensor, and orientation sensor?
I want to be able to accurately measure the static 3D orientation of a drone I am building.
I understand one way to do this is to use a gyro sensor with continuous integration.
I want to combine this ...
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Is there a circuit that I can build to allow this alarm device to operate a relay?
I would like to add a relay output circuit to this alarm device to allow it to operate my car horn.
The alarm device has 4 different tunes/tones. Each tone plays for about 5 seconds and the next 3 ...
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How does a CDROM drive sense pushback on the tray?
When you open the tray of a CDROM drive and push back against the tray, it will close at a certain point. Also, when the tray is opened completely, you can close it by pushing back against the tray.
I'...
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Help identifying weird component (sensor)
I have this salvaged part, with an unknown source. I am trying to identify what exactly this could be. Due to the clear casing my guess would be some kind of a light sensor, but googling for those ...
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FET voltage-controlled resistor schematics
I am trying to design and build a circuit that will accept a 1 to 5 VDC input and based on the voltage offer a 30 to 240 Ω resistance. I'd like the circuit to be linear.
ie R = 30 + 210 x (Vin-1)/4 ...
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Externally sensing if AC current is being drawn over a power cord [duplicate]
For a DIY project, I would like to know the on/off state of a load (on being over around 200 mA, otherwise off). For example, a smart home app tells a smart switch to turn on a fan that's connected to ...
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Sensitivity characteristics of MQ-7 [closed]
When we look at the sensitivity characteristic graph of MQ sensors, Let's take MQ-7, which is a log_log graph, we find the definition of R0 at 100ppm, this resistance is defined to be The sensor ...
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Ground loop protection watermark soil moisture sensor functionality
I am designing a little pcb where I want to read out impedance from an irrometer soil moisture sensor (example).
The manufacturer describes preventing ground loops like this:
Since WATERMARK sensors ...
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How to detect if HX711 connected to microcontroller?
I am using raspberry pi pico, HX711 , stepper and RFID. I want to make PCB for it. My system can work with or without HX711.
If system has HX711, stepper spins until the weight value of HX711.
If ...
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Calibration of MQ sensors and programming logarithmic function in MCU [closed]
I'm developing a microcontroller-based project for a gas sensor. I want to use MQ2 or MQ6, so I looked at the following sites:
https://circuitdigest.com/microcontroller-projects/gas-detection-and-ppm-...
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ESP32 DevKit not booting because of button
I developed a PCB for a project I'm working on. Today after assembling I tested everything and all relays where working as well as the ESP32 itself. Then I connected the sensors and it stopped booting....
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ACS712 circuitry with STM32F4
I am trying to measure a current of a PV module that can range from 0-15 A. The ASC712 chip can handle current from -20 to 20 A.
However, the issue is that to get a current of 15 A, the output voltage ...
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Capacitive soil moisture sensor and differential switch
While using a capacitive moisture sensor I experience this weird behavior: when I insert the moisture sensor into the ground, the line differential switch breaks. Thus, I need to disconnect both the 5 ...
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Problem with reverse voltage on old truck dashboard
I've a numeric dashboard project for my old truck that has a faulty dashboard at the moment (fuel level and water temp has wrong value, the sensors are good). In this project, I've 4 sensors that are ...
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Connecting ultrasonic transducer to PC (Data Acquisition) [closed]
I'm working on one project and need some guidance.
I aim to connect an ultrasonic transducer placed on the pipe to the PC so that I can acquire the data and then process it using Python.
I did some ...
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ADC resolution impact with voltage divider
I have a sensor that outputs a signal change between -4 to 4 V.
I want to use a bipolar ADC with a 3.3 V reference. I know that I should use a voltage divider, but what is the impact on resolution? I ...
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Component required to detect change of length
I am looking for a means to measure the length of a ca. 1 m long metal bar. Due to temperature changes it will expand and contract, and I want to be able to compensate for that electronically, say ...
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Level shifting not working properly - strange offset
12 sensor connected to an ESP32. Since the ESP32 works with 3.3 V and the sensor output voltage is 5 Vdc. I added a level shifter, in particular this level shifter mosfet.
Basically I have:
12 Vdc to ...
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Square waves (Hall-effect sensor)
I'm replacing the gearbox of my truck.
Both gearboxes (the old one and the new one) have speed sensors in the output shaft, but they don´t produce the same signals.
In order to make the new sensor ...
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Wine bottle storage quality sensor
Good evening all,
Background:
I am final year Electrical & Electronic engineering student currently in the process of completing my undergraduate thesis. The thesis topic consists of making a low-...
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Question about LM1815 implementation
After asking here a question about my motor sensor (a VR sensor or Reluctor), I've found the LM1815 chip (and also the MAX9924 but too much complex for my use). I want to use it to get the RPM engine ...
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What does "full scale" mean in terms of a triple-axis magnetometer?
I'm writing a driver for a QMC5883L triple-axis magnetometer and in the datasheet it specifies "Full Scale" as a configurable parameter which can either be 2G or 8G. I've seen this on other ...
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Question on INA122P non-linear gain
I am trying to apply gain for a 0.0 - 16.7 mV signal with an INA122P, with a single 10 V supply for all the circuits, with Vref driven at 0.0 mV.
Here is the circuit that I am using, no Rg applied, ...
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Which voltage stabilizer can be used to power the ATmega 328 and the BMP280 sensor?
I have a connection diagram of the BMP280 to an ATmega328, but I do not know which voltage stabilizer to put on the input of the ATmega328, so that it would be powered like an Arduino from 3 to 9 V, ...
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How can I use 16mm 40kHz waterproof ultrasonic transducers to measure distance?
I have these 16mm 40kHz waterproof ultrasonic transducers：Manorshi MSW-A1640H12TR.
I am wondering how to measure distance with these transducers. I desoldered the non-waterproof transducers from a US-...
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Asking experience for this flow-through pressure sensor: 26PCAFG6G - Honeywell
I have the following sensor:26PCAFG6G
The output of the signal is a differential output from a Wheatstone bridge with 0 - 1 psi, or 0 - 70.3 cmH20 corresponding to 0 - 16.7 mV, I am using AD623AN for ...
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Oscillating instrumentation amplifier with transformer coupled input
I want to amplify an output signal from a sensor. The sensor is made of three inductors which are coupled. One primary inductor with 25uH and two secondary inductors wired in the opposite direction ...
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Hall-effect sensor datasheet/setup questions
I have a few HO 6-P/SP33 Hall-effect sensors and I've been reading through the datasheet, but I can't figure out how I'm supposed to use them.
I have several questions about the information in the ...
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I need help building a low-cost contactless water sensor
I tried to build a contactless water sensor with some touch ICs, but all of them use auto calibration features i.e. they can sense the presence of water without contact but after some seconds, they ...
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Why am I barely able to read the voltage changes with this circuit?
I'm using this EMG sensor to measure the EMG signal from my bicep. However, I can barely read the voltage change from an oscilloscope when my muscle contracts - the output is a horizontal line of 1.5V ...
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Sensor that can detect the amount of smoke [closed]
Hello I'm an EE intern in a factory my given task is to desing a circuit where I can measure the difference in the amount of smoke between the filter inlet and outlet. I need a sensor to make it. I ...
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Scaling DC voltage down for use with 5 V microcontroller
I'm working on a project that requires a flow sensor connected to a PLC, and I would like to have a readout of the flow rate visible; however, the manufacturer of the sensor doesn't produce a display ...
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How to code process_state variable which reruns each time process commences?
I am making a bottle filling machine. I am using the YF-S201 water flow sensor to do the same and a 600ltr/min pump. While according to the sensor datasheet I should get the 750ml at 369 pulses, but ...
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How to read and conver temperature sensor of MAX6633 with STM32
I have a MAX6633 on a board connected to a STM32 over I2C bus. This is a 12bit temp sensor and the datasheet says it stores the temperature in a 16 bit format (I think 2x8bit).
This is how I try to ...
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Targeted voice sensing in noisy environment
My exercise, for my own interest and use, is exploring a way of measuring the relative volume of one person's voice when in conversation with a group of people.
My first idea entailed logging noise ...
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How can I read a thermocouple situation with an ESP32
The thermocouple has two pins (a ground, a 0 to -0.0004 when activate the bobbin to run the gas.) I want know how can I detect whether the gas is open or not without adding a sensor to the system. ...
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IMU for measuring body movement in water [closed]
As a swimmer I have always been curious to use my engineering knowledge in this sport. Specifically I do finswimming like the video I show below :
https://www.youtube.com/watch?v=ckKeR5EVWkk
I would ...
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Arduino Sensor data Logging
I am currently using a Teensy 3.2 to log data from a sensor. My current strategy is to print the sensor data onto the serial port using a 115200 Baud rate. I then use Putty to log the serial data into ...
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Difference between the AD8561 and LM393 comparators
I am trying to build a capacitive touch sensor circuit on a breadboard such as the one on this website, http://www.learningaboutelectronics.com/Articles/Touch-sensor-circuit-with-voltage-comparator....
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Does placing two optocoupler one below another in PCB design affect any signal?
I am working on a circuit where I am using multiple ultrasonic sensors which work on 24V, to read the sensor output through a microcontroller that accepts 5V. I am using optocoupler PC817 to maintain ...
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How much voltage does a farm electrical fence really output?
My electrical fence control unit says that it outputs "0-miles 13 kV; 3-miles 7.0k; 5-miles 6.0k", yet that doesn't seem right.
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NTC sensor in a Wheatstone bridge [closed]
I put an NTC sensor into a Wheatstone bridge so it gave me a totally non linear curve (positive and negative). How can I make it linear to read it by a microcontroller?
Thanks.
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How do you know which pin corresponds Hall sensor 1, 2, and 3 so that I can pair it with the correct phase wire in a BLDC motor?
I recently bought a brushless sensored DC motor on Amazon which you can find here.
I didn't really know what I was doing at the time when I bought this motor, but now I'm realizing it might have been ...
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Find out value of pF capacitors
I'm looking for a way to calculate value of capacitors of picofarad (pF) range. The thing is when I use a RLC meter, it looks like the device is limited to high ranges of pF to nF and so I can not ...
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How to make water flow sensor work to measure flowed water and not flow rate
I am using the YF-S201 water flow sensor. I am using this to fill up bottles. I need to know how to alter the below code in a way that instead of measuring flow rate it measures water passed through.
<...
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