Questions tagged [interference]
For questions about electromagnetic interference (EMI); see also the [emc] tag.
289
questions
2
votes
1answer
68 views
What types of cables do ferrite beads/chokes have a beneficial effect on?
Ferrite beads prevent electromagnetic interference from affecting a cable. Without fundamentally understanding how EMI works, this is obviously a beneficial effect for the stability and integrity of ...
0
votes
1answer
31 views
What's the logic inside the formula for the calculation of the maximal envelope modulation amplitude of two temporal interfering electric fields?
Since my question is a bit elaborate, I will first write some details. Thank you all!
I refer to the study conducted by Nir Grossman et al. (2017) about the use of the temporal interfering stimulation ...
0
votes
2answers
51 views
Arduino resetting or malfunctioning when controlling 48V DC motors with relay module
I'm building an Arduino controlled crane machine out of old crane machine parts.
The motors in a crane machine are 48V DC and I am controlling them with an H-bridge configuration using an 8 channel ...
0
votes
0answers
47 views
Do I2C wires and 120W (12V) power wires close together cause trouble?
I'm a beginner with electronics and I'm building my first solar powered robot. I now have a 50cm long (1.6 feet) small pipe through which I want to put four wires; 2 for the power from the solar ...
0
votes
1answer
44 views
Weird interference when controlling piezoelectric humidifier
I am trying to build an Arduino controlled piezoelectric humidifier. I am using two humidifier modules which have 5V dc operating voltage(they have usb connectors). When I connect one module to my ...
1
vote
1answer
58 views
Top layer vs mid layer for high speed ADC signal routing
Assuming we have an analog differential signal trace that we must route from the connector to,say, an ADC (24 bit or 32 bit kind as I don't think lower resolution ones are affected by this.) What we ...
1
vote
0answers
31 views
Will using a relay for triggering remote send interfering signals?
So I have a remote control with a SMD button I want to trigger. To do so, I need to bridge horizontally a pair of the pins, as shown in blue:
However, when testing this, I connected a long (10cm) ...
-1
votes
1answer
70 views
Relay board works differently with and without load [closed]
I have 8 relays controlled by esp8266 through a shift register. 4 relays on the left are under 220v load and 4 on the right are under 12v.
220v on the input splits between the left relay board load ...
1
vote
1answer
64 views
Nearby jail's signal jammer affecting cellphone and devices using 2.4GHz band
I just rented an apartment that seemed perfect at the first sight.
However, once I moved in, I noticed a lot of instability on my cellphone signal. I found that odd, so I did some research and ...
0
votes
2answers
51 views
Terminating an audio line-in signal when source is disconnected
I've been trying to DIY a home audio setup. We have a pair of speakers in the ceiling of an upper floor (previously installed), and a new TV on the same floor. We wanted the sound of the TV to come ...
0
votes
1answer
44 views
Interference suppression coils for 9V DC adapter for audio equipment
I am about to add voltage regulation to an unregulated 230V AC to 9V 150mA DC adapter, by adding an L7809 voltage regulator and ceramic 0.33µF and 0.1µF capacitors.
I want to use this adapter to power ...
0
votes
1answer
48 views
How to reduce RFID interference
I am using a MFRC522 RFID reader I have read that it's antenna when in close proximity with metals then interference could be generated. What should be the distance between the antenna and the metal ...
1
vote
0answers
35 views
PH 4502 electrical interference EMI when in aquarium
I'm trying to get a regular ph reading in an aquarium.
The sensor works well when the probe is in a small quantity of water(i.e. a glass) but has large variations in larger water quantities (i.e. ...
2
votes
1answer
42 views
Crosstalk between transmission lines
I was reading these slides about crosstalk between transmission lines. At page 6 there is this circuital model to describe the effect of mutual coupling between these two lines:
My doubt is: why \$I_{...
2
votes
2answers
127 views
ESP8266 noisy input when wires go through power supply
I had made a circuit for an LED strip using an EDP12e. I had also attached two buttons to change between colors on the strip.
To make it compact I inserted the circuit board inside the casing of the ...
1
vote
0answers
58 views
Forward and Backward Crosstalk
I have some basic questions about crosstalk. My reference for this question is this website.
This website introduces crosstalk in this way:
Crosstalk is the unwanted coupling of energy between two or ...
0
votes
1answer
72 views
Controlling a Brushed Motor with DC Voltage to Avoid EMI (no speed control needed)
I have a fairly simple project coming up. My task is to design a system which powers and controls a Pan and Tilt positioner for a camera. It has some weird and unavoidable requirements/constraints:
...
10
votes
5answers
1k views
What are some quick, cheap hacks for determining the source of EMI in my house?
TL;DR - Without dumping a bunch of money, is there a quick MacGuyver-y way to help diagnose what's causing the EMI in my house?
Longer -
I have the curse that I'm a little too technical to be helped ...
0
votes
2answers
66 views
How can I create signal interference in a circuit? [closed]
I understand that this is counter intuitive but, as an experiment I want to create interference in a circuit.
I want to expose an AC sinusoidal signal to a second sinusoidal signal. This will cause ...
0
votes
2answers
167 views
With so much radio signalling occurring simultaneously (TV, Cellphone, Radio, etc.), how does our atmosphere keep them separated and avoid disruption? [closed]
I know this question has been asked before, but I still don’t completely understand. I understand that different stations are given different frequencies, but waves are able to interfere with each ...
0
votes
1answer
46 views
Arduino relay module interferece on signal pin (230VAC moror load)
I'm trying to switch a small 230V AC motor using an Arduino Uno, but I'm having same problems due to interference on the relay (so the Arduino itself is not a problem).
Sometimes the module create ...
0
votes
1answer
45 views
WiFi Near Far Interference?
I have several ESPWROOM32 based modules that connect to a far away access point with an RSSI of -70 (it's about 50 feet away through several walls) and a close by access point with an RSSI of -30 (...
0
votes
2answers
182 views
Would twisting 3 wires together be as effective (or close) to a twisted pair?
Would twisting 3 wires together like a twisted pair would be as effective as an ordinary twisted pair? Or at least a definite improvement to not twisting them at all?
simulate this circuit – ...
0
votes
2answers
99 views
If antennae work best at full, half or quarter wavelengths, why don't received signals at 1, 1/2 and 1/4 wavelengths interfere with each other?
How does a simple radio receiver-antenna differentiate between incoming wavelengths that are the same wavelength as the antenna, one-half and one-quarter?
Or would I just hear static unless I have a ...
1
vote
0answers
44 views
Separating mains power from data lines
I'm an electronics hobbyist who's learning from wiring stuff together and searching the internet if something doesn't work. Hence my electronics knowledge is very patchy.
I recently found out that ...
1
vote
1answer
31 views
Measure antenna S11 next to another source
I have a dipole antenna designed to work on ~800MHz and 2.44GHz frequency, and a miniVNA Tiny USB device that I can use to measure return loss of the antenna. I connect the antenna directly to the DUT ...
0
votes
1answer
38 views
Mesh Wire opening size for emi filter at frequency of 30Mhz
I want to use a mesh wire and I wanted to know how do I calculate an opening size of a mesh wire that can filter 30Mhz frequency.
Your help is appreciated.
0
votes
0answers
27 views
ADVICES required PCB Design for domotic system using Odroid + STM32F103C + Different devices
I'm designing a PCB to connect all the devices I use for a domotic system together.
I have a few general questions about it and I would like to hear some recommendations to improve it as I haven't ...
1
vote
1answer
59 views
How to eliminate electromagnetic interference when counting pulses using a micro controller?
I have written a pulse counter program for ESP32 micro-controller, the counter counts the pulses correctly when there is no EMI interference but as I turn on the small AC drill machine the counter ...
1
vote
2answers
74 views
How can picked up FM noise be demodulated?
I have a set of cheap computer speakers, which happens to use a TDA2822M. Its circuit is almost identical to the example circuit from TDA2822M's datasheet. It's USB powered and has no shielding.
I ...
0
votes
0answers
58 views
Isolated step-down module for powering a Raspberry Pi from a speaker's 12V supply avoiding ground loop and interference
I have an older speaker with an iPod dock that I would like to extend with a Raspberry Pi as a streaming music player. At first, I tried powering the RPi from the dock connector with a Micro USB ...
0
votes
2answers
94 views
How exactly do inground electric dog fences work? I need help making a square perimeter with one side that dose not trigger the collar [closed]
I need help laying out an in ground electric dog fence in a square formation with one side of the square not triggering the collar. The issue it that the manufacture says that inorder to do that we ...
1
vote
1answer
58 views
Bluetooth and Wifi range onboard a boat
On my sailboat the range of wifi and Bluetooth appears to be very much shorter than in my home - I can't figure out why.
ex1:
At home I can stream video with Miracast from my basement to a room ...
2
votes
1answer
40 views
How do LTE radio networks deal with co-channel interference?
In 802.11 Wifi, I've read that a wifi adapter (like my laptop's wifi adapter/radio) will use Energy Detection to see if a channel is busy (if a certain energy threshold is detected on the channel, it ...
1
vote
1answer
45 views
Automatic mute radio on power-off [closed]
I have a small FM radio module I bought off eBay that runs off a few AA batteries, and have it essentially plugged right into a pair of PC speakers I have on all the time. To save battery power, I ...
1
vote
1answer
57 views
How many WiFi networks can operate concurrently?
Very hard information to find since Google always falls down in how many devices can be connected simultaneously to a single one network.
Is there a limit to how many different WiFi networks can work ...
1
vote
1answer
173 views
WS2812b interference and bootup behavior
TL;DR: how can a slowly rising power supply voltage on an arduino crash the WS2812bs connected to it? How can I protect a signal wire even better from electrical interference?
This my question in a ...
6
votes
4answers
220 views
What happens to parts of induction cooker magnetic field not covered with the pan?
An induction cooker works like this. There's a flat coil of wire under the cooker surface which is connected to a source of high frequency AC and it produces an oscillating magnetic field with field ...
0
votes
0answers
23 views
Downsides of Extending a USB Bluetooth Antenna?
I found an interesting video about how to extend the range on a USB Bluetooth antenna by resoldering a new antenna in its place: (https://www.youtube.com/watch?v=cwKWOdOHiWY).
I'm planning on using a ...
1
vote
0answers
45 views
Prevent Reception from an Extended Distance (Beyond Design)
I have a magnetic field that is being induced onto a power line by a transmitter, which is following the length of the power line to the receiver. The receiver communicates via a loosely coupled coil ...
2
votes
5answers
517 views
Waves on raspberrypi camera feed, Ground loops? electrical interference?
I run a video recorder in a vehicle built on Jetson Nano (Very Similar to raspberry pi). It runs on 5V . The vehicle has a 24V power supply. I power the video recorder with an automotive-grade 24V to ...
2
votes
2answers
186 views
Fixing power supply interference issue (?)
I am working on a project that involves controlling WS2812B led strips using a Teensy 4.0 microcontroller. I got everything working during the testing phase, but now, after transitioning from ...
0
votes
0answers
76 views
How to prevent common ground circuits messing with each other
I made an Arduino based 18650 battery tester that has 4 identical circuits that charge and drain.
Testing one battery at a time gives one set of results which I deem to be correct but testing more ...
7
votes
2answers
505 views
What's this noise?
As in other years at precisely this time I'm experiencing an effect somewhat like GSM frame-rate audio breakthrough in my auditory systems - completely different frequencies but equally wideband. I've ...
0
votes
0answers
188 views
Radio static caused by windscreen wipers
I was driving past a radio station transmitter of the radio station I was listening to. I turned on my windscreen wipers, which caused a noticeable static to be emitted through the speakers for the ...
0
votes
0answers
68 views
Experimenting with a Walkie Talkie
This is one weird bizarre thing which I noticed while I was in the electronics lab.
I had this Power Supply and a walkie talkie similar to this
I have not ventured in RF side yet.
The power supply ...
1
vote
1answer
38 views
How to conclude the nature of interference for such scenarios?
This is abit a hypothetical question. Imagine a signal chain where a AC-DC power supply is powering a transducer and the transducer output is coupled to a data acquisition input by a BNC cable.
Or I ...
0
votes
0answers
38 views
Touchscreen keeps failing to communicate with raspberry pi, except when I touch the INT pin
I bought a display with a i2c touchscreen from Aliexpress and hooked it up to my Raspberry Pi 3b+. The screen part works fine, however, the touchscreen part is flaky. When I just boot the pi, the ...
1
vote
3answers
925 views
2.4GHz WiFi module causing interference on 433MHz RF receiver module
I have a prototype board which has two RF modules on it, a 2.4GHz Wifi module (ESP-01) and a low cost 433.92MHz RF receiver module (Wenshing RWS-371F-6).
My 433MHz transmitter (a remote control) sends ...
0
votes
1answer
44 views
PCB with 5 Pluggable RF modules and 1 LTE puggable module - will it cause issues for reception at different antennas?
I am designing a prototype PCB which shall have 5 pluggable RF modules and one 4G LTE module as shown in the image
The Base board size shall be 240 x 140 mm, RF board size is 40 x 50 mm and LTE board ...
