Questions tagged [faraday-cage]
Use this tag when the topic is related to shielding of sensitive electronic circuits where outside influences (whether electric or magnetic) may influence how they operate so must be eliminated.
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Why does a vehicle's GPS tracker go offline when a metal chain is attached with vehicle chassis?
From my colleagues, It has come to my knowledge that attaching a 5-6 feet metal short-link chain under a truck (Mazda T3500) that is installed with a GPS vehicle tracker can suddenly cause the tracker ...
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Why do the metal sticks (for the ground) on the ground plane antenna reflect and not absorb?
From my current knowledge, any metal whether grounded (and or earthed) or not will reflect radio waves as seen on dishes, Faraday cages, etc. On the other side the ground in transmission lines or the ...
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Whats the point of the feedhorn on a dish antenna, why cant the dish just have a matching network attached to the dish directly?
Apologies if any thing i have said is incorrect. But, in the context of antennas, an unmatched feedpoint often leads to reflections, impacting both transmission and reception. It appears that if the ...
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How to protect signal routed via patch wire against EMI / RFI / other signals?
I have a delicate problem which I'm not sure how to solve properly due to my limited electronics education: I have an old computer system from the 90s which contains an additional module replacing its ...
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Is it necessary to implement a sensing resistor plus pre-amp with Faraday cage on a PCB if I would like to have the range about 10nA measurement?
I put a 60 kΩ sensing resistor plus low-bias current amplifier with a gain of 500 into an aluminium bag and tied it to AGND for EMI shielding. The second stage is an ADS1256 24-bit ADC. The purpose is ...
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Would grounded conductors placed on skin prevent signals from reaching a shielded body part?
Here is the scenario:
You are in an environment where there are sources of EM signals that your body will pick up as though it were an antenna via capacitive coupling, i.e. what happens with the 50/...
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How do I detect a Faraday bag? [closed]
How do I detect a Faraday bag coming into or leaving my store?
The intention of detecting Faraday bags is to be aware of customers who have the ability to walk out of the store with an RFID-tagged ...
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How much of my mixed-signal PCB should I shield with a Faraday cage?
I'm designing a PCB with an AFE (Analog Front-End) for measuring/recording bipotentials and I'm trying to determine how much of the circuit I should shield with a Faraday cage. At the moment, I'm ...
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Faraday Cage: incomplete graph?
I am looking to shielding for electronics, and I am reading this wikipedia article. And I wonder for this image:
Say I have aluminum (Al) of 2 mm, this means I am at 2 kHz on frequency. This means ...
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Solid Faraday cage with a hole for a wire
Is it possible to make a solid Faraday cage with a hole for a wire (to transmit information inside)?
What is needed to prevent electromagnetic waves from going through the hole?
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Better to Opto-Isolate on Sending or Receiving End? Isolating to Avoid EMI
I am working on an art project using some modified bug zapper circuitry to produce loud and bright sparks. I have the circuit working and the sparks are very impressive, but I'm running into a issue ...
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Best shielding material for a Faraday cage against 36kHz electric fields?
I have a room aka cuboid with 4 x 3 x 2.5 meters. In the 3D center is a device under test. To shield against 36kHz electric fields I want to build a Faraday cage.
I learned the hard way that aluminium ...
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Faraday Cage - Wavelength and hole size
I read about the faraday cages and understood that the size of the holes should be very small than the wavelength of the signal for effective shielding.
But I am really confused due to the ...
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Enhancing faraday cage
I have a room aka cuboid with 4 x 3 x 2.5meters. In the 3D center is a device under test. To shield against 36kHz electric fiels I have built a faraday cage by sticking 0,012mm thin and 30cm broad ...
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How do I make a Raspberry PI, EMP & Solar Flare Proof? [closed]
Is it possible to make a solar flare, or EMP proof Raspberry PI, that can still be protected while operational?
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What is the difference between a cavity resonator and a faraday cage?
In my internet research, I found that several people believed microwave ovens act as faraday cages and some said they act as cavity resonators.
I know that Faraday cages block incoming electric ...
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Would a Faraday cage still work if it was part of a circuit?
Faraday cages protect against EM radiation and charges.
As far as I understand, this effect happens through the induction of an electric field, which produces a current inside of it, which then ...
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PCB Edge "via shield" (Faraday Cage) using Altium
I am trying to add a "via shield" to my PCB edges, which is also called a Faraday cage.
I am trying to add vias using Altium software, but the vias are added outside the PCB edge and not ...
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Can you get shocked if you touch a hot wire whilst perfectly electrically insulated?
Okay this issue has been bothering me immensely so hopefully someone will be able to help me out or steer me in the right direction.
Lets say hypothetically I possessed an absolutely perfectly ...
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Mesh to block or reduce wireless cell signals
I want to block or reduce the amount of wireless cell signals coming into my house through my window(s) by using some type of mesh (screen). I could use a sheet of metal but then I wouldn't be able ...
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How to avoid RF signal loss in a conductive cage acting like a Faraday shield?
I have a standard chip antenna mounted on a large ground PCB plane.
The product is unfortunately encapsulated inside a relatively open (carbon-fiber) conductive cage.
Unfortunately, I see an obvious ...
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Steel cooker is not a Faraday cage? [closed]
I read that steel/iron/metal/conducting cages, with gaps less than the wavelength of electro magnetic waves, shield whatever is inside from that radiation. But when I put my mobile inside a cooker and ...
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Design spec for faraday cage
I need to build a faraday cage to shield from the following source: 8 Watt, 14 MHz. The signal is AM modulated
I want to build an metal box enclosing the source. I want it to shield the signal so that ...
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Negative ion generator scrambles with other electronic components in device, how can I put it in properly?
I'm making a DIY air purifier and among other things I want to put in a negative ion generator. I disassembled some Chinese product that had it in, its specs are: input voltage 12VDC, output voltage -...
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Car Faraday cage
I have been reading about the Faraday cages in the last couple of days.
My learning raised another questions about charge accumulation on a car frame.
Air friction can raise the amount of charge on ...
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External Cage AC Induction motor
AC Induction motors use an internal squirrel cage with skewed bars for the stator... However no matter how hard I look around on the internet I cannot find an external-cage AC induction motor design, ...
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Has anyone got a proven recipe to attenuate wi-fi with a Faraday cage?
I need to put a domestic wi-fi router in a homemade Faraday cage that will severely attenuate the signal. Has anyone actually DONE this?
There is lots of good advice of what should work, but few ...
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Faraday cage and static electric field
Can anyone explain - what is the difference between static and varying electro-magnetic fields?
I know the definition for what is static electric field. It does not change with time (0Hz frequency.) ...
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Will using magnetic base test indicators with breadboards cause electrical interference?
The situation leading to the question
In the Quick Tips #8 // Precision Helping Hands YouTube Video, a "helping hands" with various names such as "Magnetic Base Adjustable Metal Test Indicator Holder"...
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Is there a way to measure or predict how much a 10.5 microns Aluminum foil attenuates EMF radiation? [closed]
Is there a way to measure or predict how much a 10.5 microns Aluminum foil attenuates EMF radiation? And at what frequencies?
Is it enough to use as Faraday shield?
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Metal free zone for WiFi antenna
I am working on a project that requires me to mount a WiFi antenna underneath a roof made of metal sheet. The antenna is mounted at a 2 m height, and the roof is just a few inches above the antenna.
...
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Wouldn't putting an electronic key inside a small Faraday cage render it completely useless?
Am I missing something? The Engadget article Kia made a tiny Faraday cage to protect your wireless key from thieves says:
Many existing keyless entry systems aren't secure, but few people are ...
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Faraday cage - reducing EMI?
I am curious about the working of a Faraday cage as the shield for EMI in many systems. As far as I studied, it depends on Faraday's and Lenz's laws.
When the electromagnetic waves are incident on ...
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Would a small hole in a Faraday cage drastically reduce its effectiveness at blocking interference?
I'm shielding the pickup cavity of a guitar to minimize interference. I'm doing this with copper tape that has conductive adhesive, and I'm connecting this tape to ground.
Without getting into too ...
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Testing the RF properties of an enclosure
I need to measure RF (cellular) blocking properties of an enclosure.
Is there an off-the-shelf set of tools for doing this?
I'm assuming a MHz signal generator and an oscilloscope with an antenna ...
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Grounding A Faraday Cage On The Seventh Floor
I am working on a project for my physics class to test the resistance of various flames.
This will involve using a spark gap with high voltage and I am in the process of building a small Faraday Cage ...
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Digital Signal Cables Penetrating a RF Shielded Room
Disclaimer: I'm not a trained electrical engineer...I'm a recent Computer Science grad with about ten years experience as a RF test tech. I don't know everything, and to me, experience reigns supreme ...
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Will a cheap RFID reader work behind a 2mm aluminium sheet?
I'm building a information contact panel that will serve as a point of communication between employees and their company. Part of this process involves putting an ID card to the panel, so it can be '...
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RF Interference and Metal Enclosure
We have a product (optical detector), one client had an issue with false alarms due to their radios they use on site.
Did some modifications, added a ferrite bead to the cable and put a driven guard ...
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Faraday cage with a RF WIFI router inside - does the electricity "evaporate"?
I have a Faraday cage and inside there is a WIFI router whose RF I am trying to contain. The cage is made of aluminium mesh with hole sizes of 3 mm or so.
What happens to the RF electricity coming ...
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ungrounded chassis shielding
I'm looking into whether an ungrounded metal box provides good/bad EM shielding.
This thread seems like a definite "good", for reasons of the box acting as a faraday cage : How much shielding does an ...
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