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United States Department of Transportation United States Department of Transportation

Advisory Circulars (ACs)

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Advisory Circulars (ACs) search results
Number Title Status Office Date
20-120 Nondirectional Beacon Frequency Congestion

Recommends several actions that the user can take to alleviate problems of frequency congestion in the 190-535 kHz frequency range.

Active AIR-500 1984-06-18