Updates to Shielding the RTL-SDR with an Aluminium Case
A few weeks ago we posted about will1384 who had bought an aluminium case from Ebay and was using it to shield his RTL-SDR. After running multiple tests, will1384 discovered that the aluminium case was actually not helping with shielding performance at all. Oddly his results showed that the aluminium case was actually increasing the amount of noise received. Will has been updating his imgur album with noise analysis results from rtl_power scans over the entire spectrum.
In his latest tests he tried a metal outlet box as the case and saw improved results over the aluminium case. His conclusions seem to indicate that the aluminium box is not a good EMI shield. We’re not sure why he found these results, but one theory might be that because the aluminium case is anodized, it has a non-conductive surface, which might cause poor grounding.
![RTL-SDR in a Metal Outlet Box](https://www.rtl-sdr.com/wp-content/uploads/2014/11/metal_box-500x280.jpg)
Yup its the ground. Run a groundwire from that metal case to an earth ground, 8 foot copper rod in the soil and you get a super low noise floor.