Time scanner

The Second Doctor used a time scanner to see where he'd travel to next. (TV: The Moonbase) A similar tool was used by the Fifth Doctor. (AUDIO: Cobwebs)

Inspired by the Fendahl, Dr Fendelman created a sonic time scanner which made him find the skull of the Fendahl. Incidentally, it dragged the Doctor's TARDIS in a Relative Continuum Displacement Zone. (TV: Image of the Fendahl)