The Recall Circuit is a five-sided crystal with circuits embedded into it that, when it receives the right Stattenheim signal, can force a TARDIS back to Gallifrey. Stattenheim signals travel along the time contours of the Space-Time Vortex. In a Mark II console it is stored inside the base of the console. In a Mark VI console it is mounted on panel 6.
The Recall Circuit is almost never used and requires authorization by the High Council. However, when its use is authorized, the Time Lords can punish operators who resist its summons by steering the rebellious TARDIS into dangerous situations and then deactivating all the defensive mechanisms. Because it is integrated with the Main Space-Time Element it is difficult (but not impossible) to remove without disabling the TARDIS.
The following color code is used:
- Black: For information from the TV Series, including Dimensions in Time, and 1996 TV Movie.
- Blue: For information from the Novels and Audios including Target, Virgin, BCC, and Big Finish.
- Green: For information from 'licensed' reference sources such as the Technical Manual, Doctor Who Magazine, and the Role Playing Games.
- Red: For information from unofficial sources -The Faction Paradox series, behind the scenes interviews, author's speculation, and popular fan belief.
The TARDIS Technical Index is copyright Will B Swift.