Intercept Thresholds Panoramic, Time Base, and Audio Indicators

摘要

As part of a continuing program in the quest for an intercept indicator of optimum effectiveness, this experiment was designed to determine the average observer's success in detecting threshold signals through the use of various indicators. The panoramic presentation (panscope) threshold characteristics of an AN/APR-9 intercept receiver were determined at the Naval Research Laboratory before and after modification of the i-f and panscope circuitry. In further threshold tests, the NRL multigun analyzer was substituted for the panscope. A comparison was also made of the audio thresholds of both the AN/APR-9 and the NRL multigun analyzer. The following facts were established: (1) Narrow band panoramic systems, such as those contained in the AN/APR-9, AN/BLR-1, AN/SLR-2, etc., have relatively good response to cw signals and wide-pulse radar signals, but relatively poor response to narrow-pulse radar signals; (2) The NRL multigun analyzer, which incorporates wide approximate band circuitry and time-base presentation, is superior to the panscope with regard to narrow-pulse response and response to extremely short bursts; (3) The audio response of the NRL multigun analyzer, which incorporates high-level pulse stretching and other audio refinements, is superior to the audio response of the AN/APR-9; (4) Audio and wide-band video threshold levels are practically identical. It was concluded that more effective intercept sensitivity than is now available could be obtained by employing a combined indicator with simultaneous panoramic, time base, and audio presentations.