A Precision, Wideband Log-Video Amplifier of Large Dynamic Range

摘要

The report describes a video-logarithmic amplifier which has the following overall characteristics: an accuracy of better than + or - 1 db when compared to a true logarithmic response; the capability to match to a detector so that the combination of detector and logarithmic amplifier will produce an output which is the logarithm of the input rf pulse; a dynamic range of at least 90 db when operated from a 50-ohm source; a rise time of less than 0.1 musec. The basic design technique, circuit details, measurement data, and alignment procedure are presented. (Author)