Designing a Faraday Cage for Precision Resistor Network & DVM

[jonlg_uk]

Hello I am building a Faraday cage, I cannot find any decent information on the designing one. I plan to use it to shield a precision resistor network and 8 1/2 digit DVM in order to measure Low Frequency noise of a HV power supply.

I need to know what dictates the size of the "holes" in the shield and what is the best material to use?

 

[JaredJames]

The size of the holes is dictated by what EM frequencies you want to block out.

I'm not entirely sure, but I don't think you need holes. It depends on use.

 

[jonlg_uk]

The size of the holes is dictated by what EM frequencies you want to block out.

I'm not entirely sure, but I don't think you need holes. It depends on use.

I don't think you need holes either, however it will keep the cost of the cage down if I use a chicken wire type material. I plan to measure low frequency noise generated by a HV power supply. I cannot find any type of calculations that govern the size of these holes.

 

[f95toli]

What kind of noise are you having problem with?
Note that "chicken wire" will be completely useless if your problems are due to inductive pick-up(which is very often the case at low frequencies); in order to shield that you need mu-metal shields (with no holes).

 

[jonlg_uk]

What kind of noise are you having problem with?
Note that "chicken wire" will be completely useless if your problems are due to inductive pick-up(which is very often the case at low frequencies); in order to shield that you need mu-metal shields (with no holes).

I anticipate the main pickup will be from 240VAC and other high frequencies from microwave networks, to nearby switch mode power supplies. Ideally I would like to block all frequencies. However since I will be measuring the Low frequency noise generated by the HV power supply it is essential that I block frequencies below 100Hz.

Do you know how much a sheet of my-metal costs?