Questions tagged [detection]
The detection tag has no usage guidance.
199
questions
1
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1answer
54 views
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 ...
-1
votes
2answers
76 views
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 ...
2
votes
1answer
48 views
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:
0
votes
1answer
93 views
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 ...
1
vote
1answer
58 views
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 ...
0
votes
1answer
71 views
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 ...
1
vote
3answers
76 views
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 ...
0
votes
1answer
45 views
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 ...
0
votes
1answer
50 views
Detecting when the thermostat turns on the refrigerator
I'm wanting to monitor the power consumption of my Fridge (and Freezer) on a boat where the voltage runs from 12-15.6vDC
The Thermostat is an Inkbird(from Amazon) that closes a relay when the ...
1
vote
1answer
81 views
How to avoid false detection when using IR object detection circuit?
I have a circuit to demodulate 2KHz Infrared pulsed light which is generated by 555 timer IC and its output drives an IR transmitter circuit, which is received by IR receiver located 10 cm apart which ...
3
votes
3answers
109 views
How does this surge protection work?
This circuit signals an MCU via OU lead. I am not interested in the MCU side. I just show the concept.
My question is very simple: How does the surge protection(actually ı meant detection) part work?
...
0
votes
1answer
80 views
How to find which landline wires are mine using sensors on my cell phone?
How do I figure out which one is my line? I know there's a special tool for it, some sort of beeping proximity sensor. I don't want to buy any tools.
My cell phone, like many, has a Magnetometer. ...
0
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0answers
46 views
How to design a no-load detection circuit and auto cutoff if load is not presented?
How to design a no-load detection circuit, I couldn’t find a reference design,
Is this possible task to perform?
Load is an LED setup, 150V DC, 30mA
If load is not connected to the circuit, power path ...
0
votes
1answer
69 views
open wire detection of open drain output
I am working with a commercial dc motor speed controller it has a open drain output which can be used for generating fault signals , i am taking that output to a pcb through wire , i am giving it a ...
0
votes
1answer
51 views
Hidden wire detector, using resistor
We have on the collector of the first transistor is a resistor at 1000 ohms , could you tell us what function this resistor performs in this place and how to argue that it is at 1000 ohms
0
votes
1answer
82 views
How to detect when an LED has burned out?
I'd like to have a way to detect when a low power LED burns out (2-3.5v, 200-400mA) that is being driven using PWM from a Raspberry Pi with a MOSFET.
My understanding is that I would be able to ...
0
votes
2answers
86 views
Hidden wire detector using BJT transistors
I made a hidden wire detector from this tutorial. It works, but I'm not quite understand why. Here is the circuit:
I used 2SC1815 transistors and the value of R ...
0
votes
1answer
66 views
How to detect in the code (Not have to design any extra hardware) if a (peripheral) PCB has been inserted/ plugged/ interfaced to the main PCB?
I have a main PCB with a microcontroller on it with lots of connectors on it to connect to many other (peripheral) PCBs which have sensors and report data to the MCU on the main PCB.
I wanted to ...
0
votes
1answer
39 views
How to detect a magnetic field from a distance?
I want to detect a magnetic field, like those of small neodymium magnets, from at least 6 inches away (the further the better, I'd like at least a foot but I won't ask for too much). I'd like to do ...
0
votes
0answers
67 views
Wireless torpedo charger: Coil design and torpedo detection
I'm building an RC submarine with torpedoes and I thought a good way to power them would be with a capacitor. To keep everything water tight, I am hoping to use wireless charging. Here's a rough ...
1
vote
1answer
74 views
UART broken wire detection
I am planning to create a broken wire detection between a UART communication. The main idea was to check the Tx and Rx lines with a retriggerable astable Multivibrator which creates a HIGH Level on ...
0
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0answers
20 views
Cell size and CUT choosing in CFAR for radar detection
So, I was wondering how the CFAR for radar detection works. So, you have your received signal, the echo, and you divide it into cells, but how do you choose the cell size and the CUT?
For the ...
0
votes
1answer
87 views
Defect LED detection for car lights
The schematic beneath is a new project of me.
The theory behind this is: My car has a very fool proof bulb failure detection and warning system. CANbus proof LED bulbs can't fool the car and just a ...
0
votes
0answers
43 views
What options for detecting presence?
I'm not looking for product recommendations - I'm looking for advice on what different kinds of devices exist that would be capable of detecting the passing of an item of clothing on a rubber conveyor ...
-1
votes
1answer
64 views
Designing a frequency detection circuit [closed]
Hi i was wondering if its possible to make a digital frequency detection signal which detects which generation is being used by nearby mobile phone ie:gsm 3g 4g the frequency band varies according ...
2
votes
2answers
369 views
Isolated mains (AC) presence detector
I need to detect a AC mains outage, isolated way. Output marked as [?] goes to AVR MCU. I don't need to detect undervoltage or zero-crossings. I actually need a simple feedback to MCU interrupt which ...
-1
votes
1answer
88 views
circuit to detect chess clock toggle change to fire BT button
I was looking for simple circuit: (SamGibson's idea to add a 2nd reed switch proved possible, see update below.)
to detect transition to flat 0 V when player B's clock is running.
to detect ...
1
vote
0answers
87 views
How can I increase the distance of a photodiode
simulate this circuit – Schematic created using CircuitLab
I wanted to make a fire detection system using a photodiode, comparator with potentiometer to adjust sensitivity, and an alarm circuit ...
0
votes
1answer
53 views
Fast mains outage detector
What is the fastest mains outage detector at <1ms?
Anything that uses a 12V DC adapter or a mechanical relay is not an option for me because it has a long delay.
Is there an AC driven static/solid ...
1
vote
0answers
56 views
Composite video signal detection problem?
I have an android headunit and I installed a reversing camera to it.
The problem is that the headunit does not seem to detect the camera signal if the environment is too bright. It just shows black ...
1
vote
2answers
277 views
touch sensor for metal door handle
I was thinking if a current is applied to a metal door handled and somebody touched it that should complete the circuit to ground and be detectable but I'm not sure if this would work as the 'somebody'...
0
votes
1answer
84 views
How to get a 1 clock period pulse from a constant input? [duplicate]
I want to make a digital circuit that produces a pulse 1 clock period in duration whenever I see the input to the circuit go HIGH. I only have a flip-flop, an AND-gate, and an inverter. How do I ...
0
votes
1answer
65 views
door bell detector using NodeMCU
i modified my door bell with a NodeMCU which is now capable of triggering the door opener using a relay. Now I want to add a door bell detection to this system. I figured out two contacts which supply ...
0
votes
1answer
105 views
What type of sensor to detect if an object passes through?
(Sorry for my bad English)
Hello guys, I need your help since I have no idea about electronic stuff.
I have a table soccer and want to install motion sensors in the goals, so whenever the ball ...
-1
votes
1answer
79 views
USB type c receptacle plug in detection
How does usb device with type-c receptacle detects, that plug (just bare usb type-c plug, without cable, and resistors) is attached?
Does USB specification describe this possibility?
I know, that my ...
0
votes
1answer
36 views
Detecting signal / amplitude from 2 wire DC speaker
I want to create a circuit that replaces a 2 wire speaker in an existing electronic device. I want the device to be able to trigger an output when the amplitude of the signal that would regularly ...
1
vote
5answers
437 views
Circuit to detect broken fuse
Consider the following circuit:
[edited schematic]
DC_gen1 and DC_gen2 are two +28V dc ideal generators. ...
2
votes
6answers
927 views
Reflect IR beam off reflector instead of emitting straight to TSOP receiver
I have a working set-up to detect beam breaks using an IR LED, modulated at 36kHz, and a TSOP receiver connected to a comparator. It outputs the count via Arduino. The range is about the width of a ...
0
votes
0answers
35 views
Matched filter realization in voiceband modem?
As far as I understand, Adsl modems perform the signal detection with DSP-made matched filters. How was the same thing done in voiceband modems, for example the 56k modem?
0
votes
1answer
159 views
Electronically verify whether cable is connected to RJ45 connector
Background:
I have a device that interfaces with a motor controller over RS-485 via an RJ45 socket. Currently, the port is a standard 4x2 RJ45 connector with the RS-485 using pins 2 and 7
Currently ...
2
votes
3answers
173 views
Which is the most recommended sensor for sensing humans inside a rail passenger car? [closed]
I am thinking of an application which is necessary to know if there is and where someone is located, inside a rail passenger car or bus, for example, the problem there is many external factors such as ...
0
votes
1answer
102 views
How do I detect a pattern of 4 pulses from 4 different signals?
How do I detect a pattern of 4 pulses from 4 different signals? I want to be able to detect every time I see for example the pattern circled in blue. When I detect this pattern, I want to output a ...
0
votes
2answers
91 views
Metal detection with a coil matrix
I have an 8 x 8 grid and would like to detect where on the grid I place a metal object. I'm currently working with the TDA0161 metal detection IC, and so far have the following setup with detection ...
0
votes
1answer
100 views
How to measure load detection for ballast output 18W
I have a high performance ballast of only 18W and 36W. I would like to do a detection circuit whenever the UV light tube does not have any light out, an alarm/signal can be triggered to replace the ...
0
votes
1answer
60 views
Looking for a short range detection and identification
I am currently building a smart cat door. One of its functionalities is that it keeps the door locked until our cat comes close to it, then it unlocks the door.
I tried using RFID, the RC522 because ...
0
votes
1answer
43 views
Detection of Acoustic signals
There is a scenario: There is a certain box which emits acoustic signals at 30kHz and you are trying to detect these signals using some sort of detector.
I was wondering, would it be more efficient ...
0
votes
1answer
100 views
How to mute microphone in 2-way communication when the speaker is active?
I'm making my own two way intercom for my house. There will be a speaker and microphone above the front door of my house (as well as a camera). When someone rings my doorbell, I get a notification on ...
0
votes
2answers
113 views
Is there such thing as a Laser beam detector that returns a non binary result?
As the title implies , i'm looking for a device that can detect at what point a laser beam has been broken. So idea would be the device to output a certain voltage depending on where someone's finger ...
0
votes
6answers
156 views
Electrically detecting a not connected input
I have a 0-30V DC signal and it can be physically disconnected from a circuit. I need to detect and generate a TTL output when this signal is disconnected.
The "detector" circuit and the signal will ...
-3
votes
1answer
87 views
Detecting a feather touch [closed]
New to the forum here, but I have a need to detect a feather touch. Is there any sensor that is recommended? This will be in a vibrating environment, so audio is probably out of the question. Is a ...
