Plain English Meaning

Small selector switches on the RMI that let the pilot choose what each of the two needles on the instrument is pointing to. One switch controls one needle, the other switch controls the other needle.

Full Definition

Controls on a Radio Magnetic Indicator (RMI) that allow the pilot to select which navigation source — typically a VOR or an ADF (NDB) — drives each of the two bearing pointers on the instrument face. Each switch independently assigns a navaid type to its corresponding pointer, so the pilot can display bearings to two different stations at once.

Context Anchor

Seen on or near an RMI display when setting up which source each pointer will show.