Questions tagged [detection]
The detection tag has no usage guidance.
161
questions
1
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0answers
26 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
66 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
...
2
votes
3answers
165 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
70 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
50 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
38 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
46 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
38 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
66 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
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2answers
88 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
146 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
77 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 ...
1
vote
2answers
155 views
Package detection in datastream on FPGA
Hardware:
I have an asic-"sensor" which sends me 32-bit packages (serial). I need to detect this packages with an FPGA.
When I start the readout, the sensor is sending me data-packages until I stop ...
2
votes
3answers
181 views
Detect if 470pf capacitor is in series with motor, using only two wires
Short Version:
How can one detect if a vending machine motor is in its home position?
Long Version:
I am trying to make a circuit that would fit most of the motors used in the coil vending machines ...
0
votes
1answer
22 views
Variations in RFID USB Serial reader detection distance by connected device
I have a RFID reader that sends the TAG information over USB serial. I have had some troubles with it in a product where the detection success rate changes alot depending on what the USB RFID tag is ...
1
vote
4answers
194 views
Is this line detector safe?
I'm thinking about building a basic AC mains voltage detector. I'd like for it to be both protected and isolated, so I have a zener TVS and an optoisolator.
R1 and R3 are chosen so that between them,...
1
vote
2answers
50 views
Pulse Train Sampling Rate
Assume I have a pulse train with frequency of F Hertz. A normal square wave has all odd harmonics. From Nyquist, if I want to "Reconstruct" the waveform, sampling frequency Fs should be at least 2*(...
0
votes
1answer
100 views
SNR wall definition
I want to ask you if my understanding of the definition of the so called "SNR wall" is correct and complete. The SNR wall phenomenon is described here and here. If one has further information that ...
0
votes
3answers
90 views
How do I keep the “detected” state ON in a PIR detector until a human has left the detection area
A PIR detector stops alarming after a while, if a human in the detection area doesn't move. How do I keep the alarming state ON as long as there's a human in the detection area even if he doesn't move?...
-1
votes
1answer
146 views
long-distance sound detection/recording solution? [closed]
My general requirement is an audio input system which can effectively detect sound signal (80dB at about 5cm) over 30 meters away. The supply voltage should be within 5V so that the system can work ...
3
votes
3answers
812 views
Analog (POTS) telephone off-hook detection
With a single POTS telephone line and two or more handsets, when a call comes in, each handset can join in with the call. This can sometimes be an issue when one user doesn't know the line is in use, ...
0
votes
2answers
302 views
Non contact (contactless) AC or DC detection?
I'd like to detect AC or DC current (not the current level just nothing or something => ON/OFF) in a wire with a (DIY) sensor just in contact (glued) with the wire plastic insulator.
At the end the ...
-3
votes
1answer
342 views
Detection of lung sounds using a stethoscope and a sensor [closed]
I am currently working on a on a project for detecting sounds which uses a stethoscope, where its one end is connected to a sound detection sensor which is further connected to an Arduino board. The ...
0
votes
1answer
88 views
Voltage Detection via Analog Comparator
I'm currently designing a PCB at which I have an lithium ion battery (4.3V max) attached. The battery is charged via USB (5V).
The charging controller is enabled by a microcontroller which should ...
-1
votes
1answer
94 views
Radio frequency detection without digital clock [closed]
Is it possible to have a circuit that does something (fires a pulse, turns on a voltage, whatever) when it detects a radio signal at a specific frequency? One crucial point is that it should do this ...
-3
votes
3answers
187 views
Detecting human body current with raspberry pi [closed]
I want to be able to detect on my raspberry when a human contact is made with a GPIO pin (or a cable linked to a pin).
I am pretty sure it's possible (for example when i see this kind of projects : ...
0
votes
2answers
164 views
USB Drive detection circuit [closed]
I am building a simple portable speaker using a DFPlayer Mini, but I think that's not entirely relevant to my question.
I am looking for a way to detect when an USB Drive is plugged in, so the player ...
-1
votes
1answer
439 views
presence detection using Panasonic grid eye [closed]
I want to use grid eye AMG8833 for presence detection. Has anyone used gridEye for the same purpose?
Or
Can someone suggest algorithms to decide whether someone is present beneath the sensor or not ?...
0
votes
2answers
41 views
Sensing Mobile Battery full and cutting down power on V_bus line
I just come across the situation to cutoff the power when mobile battery full is detected (by breaking the +5v line) .I planned to implement this using high side current sensing method.When the ...
0
votes
1answer
117 views
RFID (or other) - Proximity Detector
I am trying to detect how often 2 animals 'interact'. Say I have 4 cats, I am trying to work out how often each of the cats interact with each other.
I have considered using RFID tags attached to ...
0
votes
1answer
111 views
Inductive Coil - detecting open coil
We are using an inductive coil transformer for a sensor. We excite the signal with a low frequency (1kHz-3kHz), and what we measure on the secondary indicates the proximity of a part.
Generating the ...
26
votes
7answers
6k views
Smart ways to detect a button (less power consuming)
During a meeting for a particular project I was asked to think about the way to detect a push on a button with a MCU. The detection should consume as little power as possible. At the first glance, I ...
0
votes
1answer
49 views
Phase-frequency detector not used in a PLL
My application: I need to output a voltage based on a phase difference between two input signals (a voltage and a current). It seems that a phase-frequency detector will do exactly this but I have ...
5
votes
7answers
366 views
How to detect if a nearby parked car has started engine?
We have a project with a machine servicing a car parked next to it. It's comparable to a car washning machine.
Before the machine is started, we need to be 100% sure that the engine is off. Also, if ...
2
votes
1answer
83 views
What kind of sensor could detect the valve of a rotating soccer/rugby ball? [closed]
I am trying to design a device that will detect the air pump valve of a ball and then rotate it to a home position. It will most likely be controlled by an Arduino.
I am a mechanical engineer and ...
4
votes
2answers
89 views
How can I measure moisture on a conductive flat surface as an analog/digital value?
So as the title states, the question is:
Is there a way to measure moisture on a electrically conductive flat surface?
Optionally, it would be great if I could have an indication of the amount of ...
4
votes
2answers
6k views
How to trigger hot plug detection in HDMI interface?
I'd like to trigger the hot plug detection circuit for one of my graphics card's outputs so that Windows would "think" that it has secondary monitor attached.
I know that there is a pin in the HDMI ...
4
votes
4answers
1k views
Detect and measure fog outdoors
Currently working on a project requiring me to detect fog, and measure the amount of fog. It doesn't have to be accurate but it has to give a sense of how foggy it is.
The device (probably Raspberry ...
0
votes
1answer
152 views
How to detect obstacles (Tripwire with Laser, IR or similar)
Supposing I have a glass sheet 50cm x 30cm, with 10 holes (2 lines x 5 columns), with metal/plastic (i can chose) pins inside it. They can be flush (hidden in the hole) or salient (extending 2mm above,...
-1
votes
2answers
456 views
How to detect if coaxial connection is plugged in?
I'm designing the power stages at the moment and I'd love to disable unneeded circuitry when nothing is plugged in.
Right now there are two options to plug something in to get things going: USB and ...
1
vote
1answer
241 views
Why does a foster seeley circuit need transformer coupling?
Having read most of the online references to this circuit and performed some simulations, I still don't have a firm grasp on how this circuit functions.
Here's a schematic to refresh (possibly ...
0
votes
2answers
2k views
Water leak detection sensor and circuit
I am planing to build a ROV for underwater use and at this point I am concidering to have some water leak detection system for the electronics enclosure that has to withstand underwater pressures up ...
2
votes
1answer
2k views
Test circuit to confirm RF receiver frequency? (315Mhz vs 433Mhz)
I've bought a 433 Mhz Transmitter/Receiver pair, or so I think. I cannot make them work, and I started to think that maybe the seller sent me a 315Mhz transmitter / 433 receiver pair by mistake (I've ...
0
votes
1answer
563 views
Circuit activated by pulse
Looking for a simple circuit which output is only active when its input is a low frequency (0.2-0.5Hz) pulse. The circuit output should be deactivated if input is unchanging.
I tried monostable 555 ...
2
votes
3answers
481 views
Trying to understand what I'm seeing on my oscilloscope
I've been working on this project on and off for some months now and am really at a loss as to the nature of the signal I'm seeing - really hoping someone can help me out with this.
Let me start off ...
2
votes
3answers
141 views
Lightning detection
I am planning to build a device that has a capability of early detection of a lightning. Also we want to measure the magnitude of the lightning and can anyone suggest a way to measure the magnitude of ...
0
votes
2answers
157 views
Building a (toy) Ghost Detector
I'd like to build a ghost detector. I'm only just beginning the design stage, and thought I'd reach out for some suggestions.
Receiver: I'm planning to end up with a handheld device with an analog ...
0
votes
1answer
1k views
USB plug in detection for charging port
Is there a way to detect if there is a USB cable physically inserted into a USB receptacle, even if it is just a cable (with nothing attached to it).
I am designing a USB charging port (short D+ and ...
0
votes
2answers
300 views
How to read a high voltage signal with Arduino (wirelessly)
I am trying to build a tachometer for my motorcycle, something like this:
https://youtu.be/GmLaNy2NBcQ
What I need to determine is the time between two spark plug "sparks". How could I determine ...
-1
votes
1answer
106 views
Question about Color Sensors
Can a color sensor detect more than one color at once WHILE distinguishing them?
For example: Say I wanted a program to activate only if both red and violet are detected at the same time. Is that ...
