Detection of electromagnetic emissions transmitted on the power line through electrical conduction

The paper describes the process of detecting the signals representing the image shown on the video display of a laptop. There were selected several graphical images consisting in horizontal bars of various widths and the measurements were performed in two stages using two types of chargers for the laptop: a commercial-off-the-shelf (COTS) power supply and a shielded one,respectively. There are discussed the emission levels when using the shielded/COTS power supply, as well as the insertion loss of the electronic filter within the shielded power supply.