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 30 MHz frequency.
\$\begingroup\$ Depends on material, thickness, gap and attenuation needed but about 100x bigger than the exact screen type in microwave ovens \$\endgroup\$– Tony Stewart EE75Jun 14, 2020 at 23:34
\$\begingroup\$ Please provide a method of calculation. I have an aluminum mesh wire of 1inch opening size, thickness of 0.12inch, and 30Mhz signal noise. \$\endgroup\$– Sam ShurpJun 14, 2020 at 23:41
\$\begingroup\$ How much filtering/attenuation do you want? In general, for a given material, the smaller the openings, the greater the attenuation. \$\endgroup\$– SteveShJun 15, 2020 at 0:00
\$\begingroup\$ In addition to the above, it really matters a lot about the freedom that electrons have in moving in response to EM stimulation. So the conductivity at connection points in the mesh also matter, along with other factors. \$\endgroup\$– jonkJun 15, 2020 at 1:38
\$\begingroup\$ I will try testing mesh with smaller opening size, and see if it reduces the noise. \$\endgroup\$– Sam ShurpJun 15, 2020 at 2:40
What matters is HOW FAR INSIDE THE MESH you place your sensitive circuits.
If you have 1" holes and you are 1" away from the hole, you get 6.28 nepers attenuation.
Richard Feynman wrote about this, in volume TWO of his lectures.