A Broadband, Low-Level, Error-Voltage Detector
M. L. Kuder · Review of Scientific Instruments · 1954
An error-signal detector is discussed which can resolve relatively small signals with unusual broadband response and zero drift stability. An rf chopper principle replaces the more conventional mechanical choppers which have very limited band width. Circuit and mechanical construction details are discussed. Experimental performance shows resolution to 1 millivolt with a band width of at least 1 megacycle. A zero-drift stability to 1 millivolt direct current is also readily attainable. Applications to high-speed multichannel sampling and mechanical servos are discussed.