無む線せん方ほう位い測そく定てい器き

noun

radio direction finder

Rare technical term for a device that determines the direction of a radio signal; often replaced by simpler terms like 方位測定器 or English loanword RDF in modern contexts.

See also: 方位測定器

• 旧きゅう式しきの無む線せん方ほう位い測そく定てい器きが博はく物ぶつ館かんに展てん示じされている。

  An old radio direction finder is on display at the museum.