Questions tagged [interference]
For questions about electromagnetic interference (EMI); see also the [emc] tag.
302
questions
1
vote
1answer
64 views
Power Supply issues with CAN bus
I am currently working on a system using C# for a windows GUI with an Ixxat USB-to-CAN and an STM32F303K8 that runs CANopen, The system itself is running fine I can send and receive messages to and ...
3
votes
2answers
79 views
I2C gets Interference from motors in an Arduino project
I built a small Arduino "robot" on a tracked chassis. The device uses MPU-5060 for direction finding (on a prototype shield) and Adafruit MotorShield v2 to control two 320-type motors. The ...
2
votes
1answer
78 views
SMPS grounding interference … ground loop maybe?
I am experiencing a weird phenomenon with my class 1, 15 Volt, 1000 watt SMPS with an isolated input and output grounds. The AC input (PE) ground connection has continuity to the SMPS chassis. When ...
0
votes
0answers
46 views
Is it ok to have two stepper motors right next to each other?
Would there be any issues having two nema 23 stepper motors laying right next to each other, facing opposite ways (see image)? 48v, 4amps.
3
votes
3answers
83 views
Decreasing I2C SDA SCL interference
I am setting up a fast I2C communication between a microcontroller (STM32, master) and an FPGA (Zynq-7000, slave). Currently, it won't work correctly because whenever the FPGA pulls down SDA, it ...
2
votes
1answer
62 views
DIY electromagnetic shielding (CNC mill)
I'm building a DIY CNC router. I'm running at a low RPM and only planning on cutting soft materials (wood and under, maybe a PCB).
I'm currently having problems with magnetic interference. When ...
0
votes
1answer
48 views
LTC5599: why are these baseband inputs passed through 49.9 ohms and the capacitor + SPI
I'm designing a radar transceiver board using the LTC5599. In the datasheet for the part, there is a schematic that shows the circuit configuration for the evaluation board. Here is an image of the ...
1
vote
0answers
55 views
IR reciever somewhow being triggered by cell phone screen?
First time asking a question here.
I am curious why the TSOP4838 ir sensor is acting eratically when my Google Pixel 2's screen is facing it.
As you can see from the schematic, I have a 555 arranged ...
0
votes
2answers
39 views
Shielding an RF module from noise
I feel like a fool. As seen in the image below, the nRF module is right next to the VIN terminal. When I powered this up, I was able to communicate with the nrf module via SPI but it wouldn't receive ...
0
votes
2answers
73 views
Cross-Talk/Interference between UART Lines on a PCB
I am wondering at what distance UART lines begin to interfere with each other? And can I expect the UART lines below to function properly? The PCB board below has 6 UART lines running alongside one ...
0
votes
0answers
38 views
Basic shielding practice for simple passive audio project in an enclosure?
I'm a tinkerer but not an electrical engineer. I'm constructing a stereo->mono summing box for my stereo (to listen to Beatles LPs properly, natch). I'm using the design & schematic here for ...
0
votes
1answer
87 views
How to know which radio frequency is free to transmit data over a particular frequency to avoid interference
I found that some radio broadcasting stations transmit data at a particular frequency, and I was told that if I were to transmit my own at that particular frequency that I would interfere with their ...
2
votes
2answers
106 views
Shielding powerful HF EMI
I'm trying to install a plasma cutter on a CNC machine, but the problem is that the cutter uses a high-power HF start to initiate the cutting arc, and this causes horrible interference with my control ...
0
votes
2answers
36 views
Multiple AC-DC power supplies or use DC-DC converters and one power supply?
I have an electrical control box that needs 48v, 12v, and 5v to power stepper motors, sensors, and microcontrollers, respecitvely. All power items will be mounted on a DIN rail right next to each ...
0
votes
1answer
47 views
Correct model for interference from an unterminated transmission line branch
Question about the correct mathematical model for a branched transmission line
Baseline Setup
Waveform generator: Output 10-60MHz sine wave, 8Vp-p, Output impedance 50Ohms
RG58 50Ohm coax: ...
2
votes
1answer
240 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
32 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
58 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
48 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
45 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
74 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 ...
0
votes
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
72 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
68 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
92 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
51 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
54 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
46 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
57 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
243 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
95 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
76 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
68 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
176 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
51 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
50 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
311 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
101 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
56 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
36 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
39 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.
1
vote
1answer
62 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
78 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
76 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
97 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
67 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
42 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
47 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 ...
