Hey, this is a great idea! I'll have to give it a try.
Note if you ground the copper, it becomes a capacitor relative to the AC Mains. If you don't ground it, then it is a shorted turn. These are quite different entities: one is a capacitor and the other is a very lossy transformer. Neither will help pass AC power to the unit but both will have a significant impact on any RF riding along the power cord.
My vote goes for the shorted turn effect, as that is what I would expect to see the biggest improvement. But I can try both easily enough.
Note if you ground the copper, it becomes a capacitor relative to the AC Mains. If you don't ground it, then it is a shorted turn. These are quite different entities: one is a capacitor and the other is a very lossy transformer. Neither will help pass AC power to the unit but both will have a significant impact on any RF riding along the power cord.
My vote goes for the shorted turn effect, as that is what I would expect to see the biggest improvement. But I can try both easily enough.