Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [interference]

For questions about electromagnetic interference (EMI); see also the [emc] tag.

Electromagnetic interference (EMI), disturbance that affects an electrical circuit due to either electromagnetic induction or electromagnetic radiation emitted from an external source. See

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Does Bluetooth interfere with WiFi?

I've read that WiFi b/g/n is using 2.3995 to 2.4845 GHz. Bluetooth is in between: 2.4000 to 2.4835 GHz. So what will happen when I put a Bluetooth sending device next to a WiFi sending device? Will the two devices be aware of each other (like two…
zomega
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How come radio signals don't interfere with each other all the time?

I'm a newbie on wireless technologies and I'm trying to understand how they work. One thing I don't understand is this: How come transmissions from different devices don't interfere with each other all the time? For example, I'm living in a dense…
Ram Rachum
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What is causing large oscillations in my DC/DC boost converter? Is this ground bounce or some other effect?

I designed my first PCB for a DC-DC boost converter only to find that it produced very noisy output. The design is based around the MIC2253. Here's a schematic: Although my circuit allows for different combinations of input voltages (Vin) and…
Dave.Mech.Eng
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FCC part 15 "must accept interference from other sources": what does this mean?

I've googled around a bit and here are the interpretations I've found in non-authoritative sources: that the device is unable to filter out interference caused by other certified equipment that if there is interference, the device must not…
Roman Starkov
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Why are many IR receivers in metal cages?

I'm guessing it's a Faraday cage around the receiver, but don't know why they might need one. Is there some sort of common interference around 38kHz (their operating frequency)? It's the only component I think I've used that gets this special…
R Zach
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Unusual interference

I'm experiencing an effect somewhat like GSM frame-rate audio break-through in my audio systems - completely different frequencies but equally wideband. I've noticed it occasionally in the past - always at this precise time of year. The sound is…
Russell McMahon
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Why does a simple conductor start to emit EM waves when carrying a signal?

I understand that on circuit board traces with a clock, if the higher harmonics have sufficient power, it results in electromagnetic waves being emitted from the traces which creates EMI. What I don't understand is why this happens in the first…
quantum231
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Is it possible that the phases of the moon could have an effect on the operation of certain types of electronics?

What type, what could the potential effects be, and why would this happen? EDIT: Yes, I am talking about physics not the supernatural. I figured this would be obvious unless people thought I was joking around, the tides are effected I know that much…
MetaGuru
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Microcontroller with a long wire for digital input

I have the doorbell button on my house wired into a GHI EMX dev board. The software evaluates the time of day and determines whether or not the doorbell should ring. Side Note: This was implemented as a way to deal with ding-dong-ditch pranks…
Matt Ruwe
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PCB clearance/keepout area surrounding wireless antenna

Suppose a PCB antenna or chip antenna is integrated onto a board design with a wireless IC, e.g. a Zigbee or Bluetooth module. What are some guidelines regarding clearance/keepout area on the PCB that one should allocate surrounding the anteanna, so…
boardbite
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Is it possible to jam wireless home alarm systems?

Sorry if this is the wrong community for this question but in my mind, it's the best fit. Please close or move to a more appropriate community if it's off topic. The other day, several home alarm companies came to look at my home to quote an alarm…
Classified
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How to shield microcontroller from electromagnetic interference

I'm working with high voltage circuit (2.1 kV for defibrillator capacitor testing) and I'm controlling power supply with arduino, reading required information from laptop using serial interface. Most of the time circuit works fine, but once in a…
user6266
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How to avoid interference in wireless communication?

I am working on wireless communication system. We are using around 10 pairs of transmitter and receivers. We are using atmega16 microcontroller for encoding and decoding by USART ports. Now we are able to transmit the data and receive the same in…
user934070
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Wireless Home Automation 2.4GHz versus 433MHz

Project specifications - This is an **Arduino** project - This is supposed to be internationally applicable I am working on a home automation project which might go into smaller production. The project is wireless and the connections would be…
Roberto Anić Banić
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Why does a 50 Hz, 200 mV sine wave appear sometimes on my portable oscilloscope without a probe connected to anything?

I have a portable oscilloscope, and when I connect just one probe to it, sometimes, moving the probe into the air without connecting it to anything, then I can see (in some of the places of my house) a very stable 50 Hz sine wave of around 200 mV…
Roger
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