View Single Post
Old 4th Jan 2023, 7:02 pm   #404
regenfreak
Heptode
 
Join Date: Nov 2018
Location: London SW16, UK.
Posts: 655
Default Re: 6-gang FM stereo tuner heads

Quote:
Originally Posted by Radio Wrangler View Post
They aren't Faraday cages, the metal is solid, so they also act on magnetic field components. Faraday screens are special, they are aligned grids of wires designed for purely electric field screening and are pretty much useless for general screening duties.

The idea behind the wire grids is that there is no path for circulating eddy currents.

This is a very common confusion, but it's wrong. You'll find real faraday screens inside some transformers to block capacitive coupling between windings.

These things are simple metal screening boxes, often plated steel or brass. They get soldered onto printed circuit boards over an area of componets doing something sensitive. Often the PCB has a groundplane area which acts as the lid, completing the screening box. They are a right pain for fault finding and access. They need a bigger soldering iron to remove them than they take to fit!

David
I see. The real Friday cage is often found in tesla coil demo where people stand inside;

https://youtu.be/Lqwj5bACKbU

The shields i got have clip-on bits that you are supposed to solve the de-soldering problem you mentioned.
regenfreak is offline