Transmat

Transmat — short for particle matter transmission (TV: The Armageddon Factor) — was a common technological form of instantaneous transport and many forms and designs existed throughout the universe. It was designed for matter transference: (PROSE: Engines of War) indeed it was a subset of methodologies described as teleportation.

History
Time Lords claimed to have "transcended" such technology when the universe was less than half its size and they were able to intercept transmat beams without harming anyone using them. At the time, the Fourth Doctor was charged to avert the creation of the Daleks. (TV: Genesis of the Daleks) It was still used to travel to the Death Zone on Gallifrey. (TV: The Five Doctors, PROSE: Engines of War)

This technology was available to another time-travelling species known as the Daleks. (TV: Remembrance of the Daleks, Journey's End, COMIC: The Dalek Project) Three thousand years before the second half of 20th century, it was known to the civilisation to which Mawdryn and his crew belonged. (TV: Mawdryn Undead) Sontarans used it during an attempted invasion of Earth at the beginning of the 21st century. (TV: The Sontaran Stratagem)

Mister Dread saved the Earth from destruction by using a transmat device to move a Veil starship into space. The Men in Black also used transmat devices to move objects into their vault. (TV: The Vault of Secrets)

In 2011, the Koggnossenti hubship transmatted to London from another dimension. (AUDIO: Technophobia)

By the mid 21st century, a T-Mat network was established on Earth and hacked by the Ice Warriors to invade the planet, in vain. At the time of the attack, T-Mat was monitored and controlled from the moon and distributed people and supplies, and the use of this faster than light technology meant other forms of transport were deemed obsolete. (TV: The Seeds of Death)

After the end of the Cyber-Wars, it was used by humans on the space station Nerva Beacon (TV: Revenge of the Cybermen), by a civilisation on the planet housing the Hedgewick's World of Wonders. (TV: Nightmare in Silver) and by the Cybermen themselves in the far future. (TV: The Timeless Children)

Transmats were still in use in the 49th century on human colonies. (AUDIO: Shockwave)

This technology was involved in a series of conflicts called the Transmat Wars during the 51st century. (COMIC: The Keep)

During the Fourth Great and Bountiful Human Empire (about the year 200,000), it was used on the Earth space station Satellite Five, indeed controlled by the Daleks. (TV: Bad Wolf)

Aesirian world-shapers could employ transmat beams. (COMIC: Hacked)

A transmat was used by the War Lords to travel between Berlin and Drachensberg. The Seventh Doctor destroyed the transmat. (PROSE: Timewyrm: Exodus)

Forms
Transmats existed in three forms.

Close-ended transmats
This form of transmat required a transmission/reception station at either end of the journey. The traveller entered the station where their molecular structure was scanned and stored for transmission, at which point their body was disintegrated into its component atoms. (TV: The Mutants onwards) They typically functioned at interplanetary distances, but ones powerful enough to cross the gulf between stars at trans-luminal speeds existed. (PROSE: Love and War)

While some systems transferred this physical component to the reception station, the complexity involved meant that in most cases only the structural data recorded prior to disintegration was transmitted, with a new physical form being constructed from a matter source at the other end. (PROSE: Down)

Open-ended transmats
Time Lords had at their disposal a "power-boosted, open-ended transmat beam" able to send the Master into the Death Zone. (TV: The Five Doctors)

Open-ended transmats could complete transfer trans-luminal speeds. A Dalek transmat beam moved its victim across the distance between Earth and the edge of its solar system in mere moments. (TV: Bad Wolf)

Other variants utilised a travel capsule that might have enhanced the capacity of the system's matter conversion through providing additional computing power in addition to providing protection should the location being transmatted to was hazardous. (TV: Mawdryn Undead)

The Nimon made use of transmat capsules similar to those used by Mawdryn, and they made use of black holes that dove into hyperspace, creating a tunnel with an energy beam providing motive power. A single Nimon transmat capsule could transport up to two Nimon. (TV: The Horns of Nimon)

Portal transmats
A variant of transmat opened a portal to travel from one point to another. A Dalek transmat portal was connected to Hellcombe Hall, Hellcombe Factory, Erik Graul's factory and in the trench system on France. (COMIC: The Dalek Project)

Durability
A Sontaran version of the technology, though disrupted by the Doctor's sonic screwdriver, proved easily repairable. Similarly the deployment of the T-Mat system was at least partially predicated on the ease of repairing the systems. (TV: The Sontaran Stratagem)

In 16087, the refugees of the Nerva Beacon were able to utilise a transmat to repopulate the Earth after being freed from ten thousand years of voluntary suspended animation. Admittedly benefiting from vast technological and scientific advances, they were still able to use receiver stations that, despite spending millennia unattended on a planet devastated by solar flares, remained largely functional with the only noticeable defect being a drifting of the reintegration point. (TV: The Ark in Space)

Weaknesses
Transmat capsules could damage organic structures if they were not properly maintained. (TV: Mawdryn Undead) Certain advanced species — such as Time Lords — however possessed the knowledge and technical ability to intercept and even redirect transmat beams to new destinations apparently greatly distant from those actually intended. (TV: Genesis of the Daleks)

It was generally inferred that anyone's first journey on a transmat was particularly uncomfortable, often resulting in vomiting. (COMIC: The Keep) Even subsequent trips could have been discomforting, inducing disorientation and amnesia. (TV: Bad Wolf) In his first incarnation, the Time Lord Karlax showed tingling of his fingertips for an hour and tachycardia after a trip, and insomnia in the aftermath of his first trip. (PROSE: Engines of War)

Other references
Shockeye mistook the materalisation of the Doctor's TARDIS for a transmat. (TV: The Two Doctors)

The Sixth Doctor said that the transmat always made his spine rattle. (AUDIO: The Middle)

The Eleventh Doctor thought that Brian Williams sneaked aboard the TARDIS via a transmat. Rory Williams soon revealed to the Doctor that Brian was his father, Brian having been with Rory and Amy Pond when the TARDIS materialised around them. (TV: Dinosaurs on a Spaceship)

Behind the scenes
Although teleportation technology had already been employed in the show (p.e. TV: The Evil of the Daleks) and the equivalent T-Mat was introduced in The Seeds of Death, the proper "transmat" was introduced during the tenure of the Fourth Doctor, since The Ark in Space.