Abstract: An electric field shield for non-grounded AC powered appliances is connected to a neutral return terminal of the AC power distribution system. A polarized two prong connector assures connection of the shield to neutral. By eliminating a requirement for connection of the shield to ground, shields are made available for appliances precluded from ground connection such as bedding heaters. A double pole control switch is included to eliminate E-field generation in an OFF state caused by improper wiring or the use of unpolarized intermediate connectors. The shield is insulated and a current limiting device is series connected between the shield and neutral to reduce electrical hazards.

Abstract: A wideband, passive detector of electromagnetic fields in free space is disclosed. The apparatus is especially designed to minimize amplitude perturbations of the electromagnetic field being monitored. The apparatus includes an electro-optic modulator having first and second surfaces with electrodes attached thereto and a third and fourth surfaces intersecting an optical path. An electrically small dipole or loop antenna has a first electrode connected to the first electrode of the modulator and a second electrode connected to the second electrode of the modulator, for converting electromagnetic fields intercepted in free space to a voltage signal to be applied to the first and second electrodes of the modulator. A loading resistor may be added in parallel with the electrodes to improve system bandwidth. A light source is located along the optical path, for transmitting light into the modulator through the third surface.