I have more to go on. I live in an older house that is near an open delta primary (unbalanced EMF) and the house has some ground issues I have not tracked down yet. As a result the meter is in a 4.5 to 5 milliguass fluctuating AC field. Hand or body motion will temporarily affect affect the field. I went for a walk and I was able to get the field down to 0.6 milligauss. The pattern became more random as I got away from overhead power. I now believe the previously reported pattern was the resultant field from the missing leg on the overhead power line. Even in a 0.6 milliguass AC field non contact motion effects the meter. Since the the EMF around the equipment I work on is often much higher than the 5 milliguass field, the meter would have a good amount of error using an external current clamp that outputs in the milliamp or millivolt range. The buffered graph would have induced noise that may not be part of the measured signal. The noise would cause many problems with accurate power measurement if a millivolt signal were scaled to reflect measured current.