Faraday Bag Testing

All of our bags tested independently, if you wish to find out more about the testing results please download the following lab test PDFs below.

Faraday Bag Testing 2016 Report

Overview

Following the conception of small electronic devices and their applications in recent times, there is a growing need to determine and test the shielding properties or shielding effectiveness (SE) of their enclosures. In this paper, we discuss how a reverberation chamber technique employing a comb generator can be used to measure the shielding SE of such enclosure.

The comb generator has been a necessary test instrument for electromagnetic (EMC) test labs over the years and because of its ease of operation, it has found application in a variety of EMC test measurements such as cable loss measurement and radiation emission system test.

We present here the result of testing the SE of a Faraday enclosure bag in a small RC-like cavity employing a broadband bowtie receive antenna and the same test procedure conducted at a 1 metre distance from a receive antenna in a standard mode stirred reverberation chamber (MSRC). The striking positive correlation between these test results seem to suggest that SE tests of Faraday bags can be conducted in an RC-like cavity which is significantly less costly and offers a cheap alternative.

Faraday Bag Testing 2014 Report

Overview

These initial results are for the Tablet Shields only. The photographs of the bags are presented in figure 1 and figure 2 respectively, to demonstrate which product is being tested. A bow tie antenna constructed from enamelled copper wire was used to provide a source with a wider bandwidth than that of a dipole. Noise level tests of various types were performed without the antenna and with a load instead.

These provide a baseline for measurements. When results were found to be noisier than expected, extra copper tape was added to cover the opening where the cable driving the antenna from the VNA entered the bag (clearly in real applications the source would be fully enclosed). The shielding effectiveness results compare the ‘naked’ (unshielded) antenna with the shielded antenna.  The test method was to measure the shielding effectiveness by taking the difference between the exposed antenna and the antenna enveloped in the bag when placed in a reverberation chamber, as undertaken in previous tests.