Signal drifting/EM signal/Faraday cage/metal box with connector

[Chengjun Li]

Hi,

I am using a evaluation board to measure extreme small differential capacitance on the aF scale. I always got a drifting output, although the speed of drift is slow. I think this might due to the influence of environmental EM signal. I want to use a faraday cage to isolate the EM signal. The faraday cage is better to have connectors on it. I used to see somebody else use a metal box with connectors on it, but I don't know how it is called. Does anyone know where can I buy such a box or what it is named? I didn't find any item by typing faraday cage on DIGIKEY.

Thanks,

 

[dorke]

They are called "EMI/RFI shielded boxes",mostly of aluminum.
You can make one yourself for much less,use any tin box and add the connectors you need for signals.
and feed-through caps for power.