High Frequency Direction Finding Research for Shipboard Use: Direction Finder Radio, Shipboard Siting and Design, Study and Development

摘要

Completion of repairs to the AN/SLR-10 spaced-loop antenna including satisfactory access door gaskets is reported. Initial tests on the AN/SLR-11 particularly the antennas and preamplifiers were performed. Equipment developed a number of years ago for azimuth curve plotting was extensively modified in order to replace an obsolete X-Y recorder and to reduce the size and weight of the equipment. The final experimental work toward the selection of a crossed spaced loop direction finding geometry is under way. Mechanical design of the model to be shipboard tested was started. Electronic tuning will be used in the upper frequency range from 2 to 6 mcs, and a self-calibration feature will be included to insure balance of the tuning circuits. The need for more information on required bearing sensitivity is mentioned. Lacking such information, new calculations are under way to set recommended sensitivity requirements for future designs especially in the lower HF range.