The primary and secondary Relative Dimensional Stabilizers (RDS)
are found in their respective Control Rooms.
They are responsible for creating the size,
shape and form of a TARDIS's interior.
The sphere of the Core Service Module is surrounded by a grid of matter control projectors which the Dimensional Stabilizers use to maintain the Module.
Because they allow the operator to cross three dimensional barriers a TARDIS can not travel the vortex without them.
The stabilizers are also an essential part of the Temporal Grace Field. Monitoring and controlling the RDS takes up more of the Artron Mainframe's processing power than any other function.
Vintage Mark I consoles have very primitive Stabilizers in comparison to later models.
The Relative Dimensional Stablizers cycle continuously when a TARDIS is in flight and can sometimes be faintly heard in the Control Room. The sound is clearly audible on the exterior when a TARDIS materializes or dematerializes.
This sound is slightly different for different types of TARDIS.
If
the TARDIS is badly in need of an overhaul the Dimensional Stabilizers will sound different almost every time there is materialization.
Dimensional Stabilizers
have
Probability Compensators
that can be used to fix some kinds of space-time anomalies.
They
can seal cracks in Time that lead to Parallel Universes,
repair damage to the time lines, and act as temporal decrystallizers.
In an emergency
(and using codes available only to the Lord President)
the Stabilizer can be used to control Gallifrey's defense barriers. With a few simple modifications the stabilizers can alter the size of people or objects.
This is same basic technique
used by the Master's Tissue Compression Eliminator.
Like many pieces of Time Lord technology, the stabilizers will interface with alien technology automatically.
Removal of the Stabilizers' Dimensional Control shrinks the interior micro-universe (all the rooms within it) down to the size of doll house (see illustration). Dimensional Stabilizers can suffer failures of synaptic adhesion or their chronostat can fail. If a TARDIS dematerializes without the Stabilizers being fully active, then the internal gravity will go into a "spin."
If the Stabilizers are completely disabled, then the life support systems become inoperative.
In an emergency the Gravitic Anomaliser can be used as a dimensional stabilizer if the main stabilizer is fused.
A primitive Relative Dimensional Stabiliser can also be constructed out of the drive circuits of a ship equipped with a warp drive using the following procedures: