Questions tagged [detection]
The detection tag has no usage guidance.
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How to convert a varying 28~60V DC high into 3.3V？
I want to design a PCB, include a GPIO of a MCU detecting the on and off of a LED driver. The LED driver input is 220V 60Hz, the output varies between different LED within 28 to 60V DC. My intuition ...
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Help with circuit for school
I am doing a project for school with two friends. We are going to make a DIY metal detector. We are using a source as our circuit. Can someone help us describe what is happening in the circuit?
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How can I detect when football passes through a hula hoop?
How can I measure whether a football passes through a hula hoop? The main challenge is the need for outdoor use, which presents difficulties due to the presence of ambient light (sunlight).
It might ...
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How can I detect when a signal becomes noisy?
I'm using a sensor to measure water potential. We record the output value every minute. Up until 4/16, the signal is pretty clean but I need some sort of way to detect when the signal starts to get ...
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Second power supply detection
I have a power supply (5v) and I would like to detect when a second power supply of the same voltage (5v) is added to the circuit, the only idea that came to my mind is:
My idea:
To measure with the ...
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Mains AC detection circuit - will it work?
I´m trying to detect mains voltage (230 VAC) across AC_SENS_L and AC_SENS_N.
AC_SENS_IN goes to an Arduino input with pull-up.
I only need to detect if voltage is present, not what voltage.
Any ...
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Best way to detect failing batteries
I have a few IOT products scattered around long distances, they use solar and batteries to run. They are LiFePO4 12.4 V systems deployed in the South East US.
I have them report all the data available ...
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362
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Any way to test continuity of a potentially live circuit?
I'm trying to add an indicator to a relay circuit; specifically, I want to know if it's open or closed in a way that can detect contact welding. (I considered a DPDT relay, but it looks like these ...
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Choosing the right LED IR and the photodiode for optical beam sensor
I need to design an optical beam sensor for about 15-20 cm of distance - any obstacle between an emitter and a detector would trigger an interrupt for a microcontroller.
I was thinking about using a ...
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Trying to develop a peak detector circuit
The circuit below has as an input a sound wave that is amplified (the op amp used is an ideal one) that then goes through a peak detector circuit. I intended to implement part of this circuit using ...
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How to detect a sine wave signal to trigger a logic gate? [closed]
I need a way to detect a signal input and then output it as a logic high. The signal input has a 40 kHz frequency and it's a sine-shaped signal. The amplitude is not sure, could be from 12 V to 1 V.
...
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Detection device for robots [closed]
I am an electrical engineering student and I have been in robotics since 2019. I want to create my own robots and I need advise on a detection device.
Context :
The match happens on a 1m×2m table, 2 ...
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How to detect whether the a 2-position fan connector on a PCB is plugged or not without turning on the fan?
On the PCB just a simple circuit to drive a 2-wire fan when we plug it to a 2-position connector on the PCB.
Is there a way to modify something on the circuit to know if the fan (DC motor) is plugged ...
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887
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Thermocouple short-circuit detection
I'm trying to figure out how to detect a shorted K-type thermocouple (between the wires, not a wire to GND or Vcc.) I would define a short as thermocouple resistance < 0.1 ohm as opposed to 1 ohm ...
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Extending signal duration
I have DMM which is producing pulse with duration of around few microseconds. The pulse need to be sampled in PLC, which has sampling rate of 1ms. In other words the cycle loop can't be reduced to ...
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Is it possible to build radar system for drones detection at home? [closed]
Can I build DIY radar system using ESP32 or Raspberry Pi modules + a bit of soldering that will be able to detect drones in a radius 1-2km? Is it possible? What do I need for this and how much will it ...
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How to safely protect input sensing AC Line Voltage
I'd like to detect the presence of AC line-level voltages in my PCB project, and I'd like to follow best-practice for doing this. I'm a controls engineer so I'm happy with dealing with mains with ...
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How exactly does a breaker finder work?
I've used a breaker finder for a while now, and I'm curious as to how it actually works. The only explanations I can find online are layman explanations (e.g. it sends a signal up from the outlet to ...
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Detecting magnets regardless of polarity
I'd like to build large matrix of sensors to detect objects placed on it. I can place magnet or metal inside detected pieces. I tried to use reed switch and hall sensors. Hall sensors seems like ...
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Problems detecting button pressed when waking up a MCU
I'm designing a device to activate a mechanism when a specific number code is typed on a keytpad. In order to save battery life (it is powered by 3 AA batteries), I have configured the MCU to go to ...
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Get alpha-beta plot of Clarke Transform in Python
For a project I'm working on, I want to use the Clarke Transform to detect faults in a power system. To do this, I already wrote a script in Python which returns the sine wave behavior of the Alpha, ...
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Difference between a normal tactile switch/pushbutton and a detection switch/pushbutton
What is the general difference between a normal tactile switch/push button and a detection switch/push button?
I have heard that if in an application, for example, a pushbutton has to be pressed for a ...
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Replacing relay for solid state alternative to detect if a connector is plugged in
I'm adding an extra LED light to the trunk of my car stuck to the removable shelf through a magnetic connector (Aux connector). I want the original light not to work if the new light (LED) is plugged ...
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Cleaning up tacho generator signal triggering false interrupts
I'm currently having trouble with detecting the RPM frequency from a tacho generator signal. I have tried everything I know.
My tacho generator is attached to a universal washing machine motor, and it ...
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Measuring the amplitude of a nV signal of known frequency and phase using AD633
I am wondering if there is a circuit to measure the amplitude of a sinusoidal signal of known frequency and phase that is induced in a pickup coil. The amplitude would be in the range of 0nV to ...
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Detect if external LED is on from ESP8266
Intermediate DIY-er needs advice.
I'm trying to detect if my Air Conditioner power indicator LED is on from ESP8266 microcontroller (Wemos D1 Mini).
The indicator LED is on a small PCB module with a ...
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Converting a PWM signal to reduced constant voltage or constant current output
I'm dealing with an existing circuit that was originally designed to dim incandescent and halogen bulbs from 12V using low frequency PWM. This PWM is visible to the naked eye when substituting a 12V ...
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How is this circuit detecting the LED?
so I've just built a circuit and some Arduino code (not shown here) which interfaces between a car steering wheel and its buttons to an aftermarket cruise control system (Command AP500). The stock ...
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48V Lithium Battery Cutoff Detection Circuit
I'm building a power system using four x 48 V 100 Ah lithium batteries in parallel (48 V 400 Ah nominal). The batteries are already purchased, there is no going back. The cells cannot be accessed, ...
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How does a grid-tie solar power inverter know when the mains power has failed?
Solar power inverters that send excess solar power back to the grid are (usually) required to shut down if the grid power fails. (This is to protect people working on the power lines.)
The inverter ...
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Friendly target identification in radar
Crossposted from Signal Processing stack exchange,
How do radar systems identify friendly targets to avoid AA locks during combat scenarios?
Do friendly planes broadcast a known signal or is something ...
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Circuit to detect in which port sensor inserted
I want to build a Counter using a Proximity Sensor. I want to give choice for user to use either PNP or NPN. I will give two ports for the same. I am using PIC16f887 microcontroller.
How to detect ...
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Open circuit fault detection using an Arduino
I was able to implement short circuit fault detection of under ground cables and I was also able to add a GSM module(SIM900D) with it.
I'm trying to further enhance my project by detecting open ...
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Can LED strips be used as photodetectors?
As I did not find any photodiode/PD strips available, I am wondering if it would be possible to use LED strips as photodetectors. And if yes, which type of LED strip could be used for that purpose?
My ...
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Amplifying 40ns pulses that come at unknown times (for single photon detector)
I have a single photon detector produces a 40ns signal when a photon enters the detector, like the image below:
I would like to take this electrical signal and hook it up to this device which simply ...
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Reliable 110 & 230V AC line detection on 3.3V GPIO
A manufacturer provided the following circuit, to detect AC line voltage in a small IoT module (non-isolated power supply).
SW1 is pulled up with an external 10 kOhm resistor and connected to the ...
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How to detect AC or DC voltage from 9V DC to 250V AC?
I have a device that needs to detect the presence of voltages from 12V DC up to 240V AC RMS (Absolute maximum of 9V DC to 250V AC RMS) This device is going to have up to 8 channels that should be able ...
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How to detect a capacitor installation
The circuit I'm designing uses external capacitor to measure its ESR. I use MSP430 as a controller, capacitance of the external capacitor can vary between 100n and 10uF. The problem is I should ...
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General approach of signal detection after demodulation of BPSK
I'm very new to electrical engineering. I'm trying to understand the basic approaches/options to detect symbols after demodulation of BPSK. I found some articles mentioning Maximum Likelihood ...
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Does the bandwidth at the receiver really affects the noise in digital modulations?
I know that, in a telecommunicacion system, the AWGN power after going through the receiver filter is
$$
P_z = KTB
$$
where B is the bandwidth of the filter, T is the operating temperature of the ...
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How to detect the presence/ absence of a PWM signal on a GPIO pin?
I just want to set or clear a flag by detecting the presence or absence of a PWM signal with approximately >100 kHz frequency on a GPIO pin. I studied that a simple RC low pass filter can be used ...
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How to detect an I2C target's presence/absence as an interrupt?
Involved in a task to build a test equipment with a ARM M4F microcontroller for the purpose of testing various PCBs. One of the PCBs has I2C compatible current/voltage monitoring chip on it. Is there ...
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Which sensor should I use to recognize just humans? (not all of the obstacles)
I would like to make a social distance meter and the device should only avoid from humans, not the obstacles. I'll use an ultrasonic sensor and a PIR sensor but I'm not sure it will be enough. Do I ...
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Why can FM be demodulated non-coherently while PM cannot be demodulated non-coherently?
I have read that frequency modulation has the advantage that it can be demodulated non-coherently while phase modulation can only be demodulated coherently.
I don't find any reason to support this ...
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Why is transformer coupling used in a simple slope detector? Can't the FM signal be applied directly in parallel to a tuned circuit?
This is what I mean by simple slope detector:
Why can't it be like:
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Is it possible to use a Multimeter for detecting electric leads?
Is it possible to DIY my multimeter into a detector for active wires (charge flowing at that very moment) inside a wall?
I don't know, maybe something with a coil or metal plates?
The application ...
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Help recognizing components and parts of this radio telescope [closed]
I stumbled upon this video, where someone is showcasing a radio telescope that detects wifi frequencies and renders them as picture.
There are three parts, and the one above is just the 3rd part (last ...
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Can a voltage divider be used for (input) jack detection?
I would like to detect when a jack is plugged into my connector. The circuit looks like this:
One end of the jack is connected to a speaker, and the other to an audio source, such as a phone or mp3 ...
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Why the same sound source (low frequency, possibly infrasound) has different frequencies in different rooms of the house?
Can someone explain me why the same sound source has different frequencies in different rooms and if there is some type of correlation between the vibrating frequency and the distance between the ...
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Composite video from rear car camera - bad signal (wrong levels?)
I have bought a car radio (AMPrime 4022D) that has ability to connect rear camera to it, so you can see the image on its screen. The problem is that radio doesn't detect the signal (blue screen).
But ...
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