Multi-channel electromagnetically transparent voltage waveform monitor

Abstract

A multi-channel electromagnetically transparent voltage probe transmission link system for monitoring a plurality of voltage signals at a plurality of test points of a device under test that is subjected to a radiation field. Each channel includes two voltage probes, an electrical to optical signal transmitter, an optical signal transmission line and a receiver located out of the radiation field. The voltage probes contact and sense the voltage signals at the test point. The electrical to optical transmitters are removably mounted in a common base and are powered by either a common (or shared) power supply and/or by dedicated power supplies, such as rechargeable batteries. The receivers process the optical signals and provide display signals corresponding to the sensed voltage signal at the plurality of test points for evaluating the effect of the test radiation field. An attenuator which may be electromagnetically transparent is provided for attenuating a sensed voltage signal to a range suitable for processing by a transmitter device having a limited input range, over a frequency range of interest. The input circuits to the transmitter are provided with a centertap which provides a return current path for the voltage signals of the device under test that are sensed by a voltage probe. Low power consumption and low voltage drift circuits are used.