radio direction finder
Also found in: Dictionary, Thesaurus, Acronyms, Wikipedia.
Related to radio direction finder: Radio direction finding
radio direction finder[′rād·ē·ō di′rek·shən ‚fīn·dər]
A radio aid to navigation that uses a rotatable loop or other highly directional antenna arrangement to determine the direction of arrival of a radio signal. Abbreviated RDF. Also known as direction finder.