Stattenheim remote control
A Stattenheim remote control was a device used by Time Lords to control their TARDISes.
The Rani and the Second Doctor each had used a Stattenheim remote control for their TARDISes, (TV: The Mark of the Rani, The Two Doctors) as did Template:Frontier, who created one to retrieve his. (PROSE: First Frontier) The act of whistling was not technically required, but was useful to focus the mind to "call" the TARDIS to the user's location. (PROSE: Timewyrm: Exodus)
The Second Doctor had been granted his by the Celestial Intervention Agency, and he had used it in many of his post-War Game adventures. (PROSE: World Game, TV: The War Games, The Two Doctors) The Master once tried to steal the Second Doctor's remote control. (GAME: Destiny of the Doctors)
