Blocking ISM band frequencies

In summary, the ISM band is a set of frequency bands from about 6 kHz to 246 GHz and there are ways to block these frequencies using a Faraday cage. It is recommended to use a single Faraday cage with small holes to effectively block the entire band.
  • #1
bigplanet401
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0
The ISM band is a set of frequency bands from about 6 kHz to 246 GHz; see http://en.wikipedia.org/wiki/ISM_band#ISM_bands.

Is there a design that will block all of these bands? A guess is in the attached file: each box is solid metal or wire mesh, and the boxes nest in a Matryoshka-doll fashion.
 

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  • #2
If one of your 2.4 GHz devices is being interfered with, you may want to check out these ways of resolving interference.
 
  • #3
My question's a little bit broader than that. I'd like to block as much of the ISM band as possible and would like to know if the design shown in the drawing (which is like King Tut's tomb; see below) is a reasonable approach. Will nesting, say, 4 Faraday cages each with different mesh sizes block four separate bands of frequencies?
 

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  • #4
bigplanet401 said:
Will nesting, say, 4 Faraday cages each with different mesh sizes block four separate bands of frequencies?

Its more likely to block everything
a gridded/holed Faraday shield, like a waveguide is basically a highpass filter

Consider the holed grid of a microwave oven, it blocks everything up to and a little beyond ~ 2.5 GHz
everything higher in freq above that goes through up to light and beyond

so if there is something inside the box that you want to be able to receive say 450MHz
that signal will be filtered out

I think you need to explain in much more depth what you are trying to achieve

regards
Dave
 
  • #5
"King Tut's tomb design", Lolo0)
 
  • #6
Building a cage that blocks the high frequencies will block all below it. As davenn said,
"Its more likely to block everything a gridded/holed Faraday shield, like a waveguide is basically a highpass filter"
 
  • #7
A microwave oven is designed to contain it's working frequency via a 1/4 shunt constructed along the periphery of the door. Thus wide bands below and above the design frequency will leak through the gap around the door. To get wide-band performance, the door would need a conductive seal all around.
To seal RF in / out, totally constructive chambers are constructed with conductive spring fingers all around the doors. Absorbent materials are usually included along the walls to suppress resonances.
 
  • #8
To seal RF in / out, totally constructive chambers are constructed with conductive spring fingers all around the doors. Absorbent materials are usually included along the walls to suppress resonances.

Sorry, but what is a "constructive chamber"? I couldn't find it on Google.
 
  • #9
You still haven't told us what you are trying to achieve

doing so will help you get better answers, at the moment we are all just guessing
 
  • #10
One faraday cage will solve the problem. You do not need to nest multiple faraday cages.
Make sure that any holes are smaller than about one tenth of a wavelength at your highest frequency.
 

What is the ISM band?

The ISM (Industrial, Scientific, and Medical) band refers to a group of radio frequencies that are designated for use by industrial, scientific, and medical devices.

Why would someone want to block ISM band frequencies?

There are a few reasons why someone may want to block ISM band frequencies. One reason could be to prevent interference with other devices operating on the same frequency. Another reason could be for security purposes, to prevent unauthorized access to sensitive information being transmitted on these frequencies.

How can ISM band frequencies be blocked?

ISM band frequencies can be blocked using various methods, such as using specialized shielding materials, applying filters to block specific frequencies, or using jamming devices that emit signals to disrupt the frequency.

Are there any potential risks associated with blocking ISM band frequencies?

Yes, there are potential risks associated with blocking ISM band frequencies. These frequencies are often used by essential devices, such as medical equipment or industrial machinery, and blocking them could cause these devices to malfunction. Additionally, blocking these frequencies without proper authorization may also be illegal in some countries.

Are there any regulations regarding the blocking of ISM band frequencies?

Yes, there are regulations in place regarding the blocking of ISM band frequencies. In the United States, the Federal Communications Commission (FCC) has strict regulations on the use of jamming devices, and blocking ISM band frequencies without proper authorization is illegal. Other countries may have similar regulations in place.

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