One of The Doctor’s more frequently used gadgets. It is roughly the same shape and
size as a screwdriver. It was a versatile tool and defensive weapon used by the Doctor.
This made its first appearance in the serial ‘Fury from the Deep’, and has been used throughout the series’ ever since, though it has been through several different models and designs. The name implies that it operates through the use of sound waves to apply a physical force onto objects, such as locks.

Functions
• Opening virtually any lock, electronic or mechanical. However, it has absolutely no effect on a ‘deadlock seal’.
• As an aid to repairing objects and machines.
• Detecting things (such as signals, booby-traps and antimatter)
• Sending signals.
• Fusing metal, such as barbed wire (which has its own setting)
• Intercepting teleportation.
• Driving screws.
• Igniting marsh gas
• Activating processes or functions inside the TARDIS from outside.
• Burning, cutting, or igniting different substances.
• As a radiation detector.
• Amplifying sound, usually to stun an enemy.
• It was once used it to detonate land mines from a distance.
• And once used as a ‘miniature sonic lance’ to cut out a lock.
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