You need the proper meter to measure dirty electricity, a Graham/Stetzer Microsurge Meter.
They work as they are proclaimed to do. Someone above was complaining about the filters not working. He is not checking the right thing when he uses a Gauss meter as it seems that he is. A Gauss meter measures RF field strength, electromagnetic radiation, and electrical radiation, three different types of EMF fields. The Stetzer filter addresses the problem of dirty electricity on power lines primarily and a different meter is used to determine levels of dirty electricity; the proper meter is a Graham/Stetzer Microsurge Meter which measures average (dv/dt) high frequency, non repetitive electrical noise on the wires. I just used my Stetzer meter to measure the circuit that her reading floor lamp was plugged into (no filter) and got a reading of 148 microsurge units with a maximum of 50 being the target. After installing a filter reading dropped to 30.
Rating: 5 stars