Time path indicator

The time path indicator was a component of a TARDIS used to detect time machines in the Time Vortex which were on the same flight path. It could also be removed from the console and used to detect time machines.

The time path indicator in the First Doctor's TARDIS signalled its crew that the Daleks were following them in the Dalek time machine following their escape from Aridius. (DW: The Chase)

The time path indicator also registered when it detected the Master's TARDIS near the Darkheart system. (MA: The Dark Path)


 * Presumably, the Fourth Doctor used the time path indicator to follow Scaroth to prehistoric Earth. (DW: City of Death'')

The Seventh Doctor, having received a warning about the Timewyrm, removed the time path indicator from the TARDIS so he could detect its coming. (NA: Timewyrm: Genesys) He later used it to track her down after she escaped. (NA: Timewyrm: Exodus)

It is not known why the mechanism did not warn the Fifth Doctor or the Tenth Doctor of their collision. (DW: Time Crash)