[Joeztech]

Ron;

You confirmed my suspicion on this. The electrostatic shield is never a completely closed loop. One end is always left dangling electrically, but it provides an electrostatic shield that minimizes interference from florescent lamps and neon lights and somewhat against sparks jumping from poor electrical connections. If I remember correctly this was developed shortly before WWII and at first was intended for the military, but wound up being applied for AM radio. It shows that Philco engineers were staying on top of new developments just as they did earlier in the 1930s. They had a top notch group of engineers and technical staff. Philco appears to have developed this idea and patented it. See: http://www.freepatentsonline.com/2273955.html

The electrostatic shield combined with the ability to rotate the inner loop so that it is parallel to the originating signal captures the best most noise free signal.

Joe