The Timelost Travelers acquired or were exposed to several pieces of advanced Time Lord technology during their adventures, not the least of which was the TARDIS itself.
A TARDIS, or Time And Relative Dimension(s) In Space, is the name used by the Time Lords of Gallifrey for their space-time travel capsules. TARDISes are transdimensional in nature, with the interior existing in another dimension linked to the exterior shell through a real space interface. The interior dimensions of the TARDIS had no relation to the exterior size; the common phrase used was that they were bigger on the inside. The default appearance of the exterior shell was a nondescript off-white cylindrical cabinet, but the craft's Chameleon Circuit could cause the exterior to take on nearly any conceivable appearance, a useful trait that allowed a TARDIS to blend in with its surroundings no matter when or where it traveled to. The interior was also configurable, with the operator able to move, add and remove rooms as well as change the layout and decor. There were a few standard features on all TARDISes; they required a key of some kind to get into and had a main control room that was directly accessible from the exterior door. TARDISes also had a variety of defensive capabilities as well as a suite of sensors. TARDISes were also alive in some sense, imbued with what some might term a spirit or soul that existed outside normal time and space. A TARDIS could sometimes interact with its crew in an empathic or telepathic manner, and at times could be at least semi-autonomous, but their consciousness was usually too alien for anyone to truly comprehend or communicate directly with it.
The TARDIS used by the Professor was an older Model 50 but otherwise typical for Gallifreyan space-time craft. Ever since it was badly damaged in 1986 the TARDIS's chameleon circuit has been broken, locking the external shell in the appearance of a generic 1980s cola vending machine. Other than minor variations (such as the Out of Order sign that is sometimes attached to the outside but on some occasions is not present) this outer shell has remained consistent since the TARDIS was found in 2017.
When the Professor initially went into hiding on Earth his TARDIS' interior was still more or less the standard appearance, a vaguely futuristic looking white and off-white still dominating. After it was badly damaged in 1986 the TARDIS was forced to slowly repair itself and as a result much of its interior started to reflect its outside surroundings, namely a high school from the 1970s and 1980s. A later overhaul happened after the TARDIS crashed in the 1860s after which the interior took on a Jules Verne-Victorian Era Steempunk aesthetic. Most recently, after the TARDIS was nearly drained by a Weeping Angel and was revived with the time essence that had once been the Professor it once again took on an interior appearance of a school.
When the time travelers first boarded the TARDIS they had little opportunity to look around, and the interior still had a damaged appearance. After the TARDIS used the energy of a time rift to complete repairs, the group were able to get a better look around. In the main Control Room the walls and floor seemed reminiscent of the school, with walls and floors that seem to mimic the classrooms; there was even a chalkboard on one wall, though no chalk or eraser to be seen. In the far corners were a pair of wrought-iron spiral staircases leading up to a walkway that went around three sides of the room, and looming above the short hallway leading from the cola machine entrance is what looks like the interior of a clock tower similar to the one that sits atop Centennial High School. The clock face and, apparently non-functional, clock face can be seen from below, and by climbing up onto the walkway a person could look out through the clock face and see the surroundings outside of the TARDIS, as if there really was a clocktower on top of the craft (though it was never visible from the outside). In the center of the Control Room was the central Console, looking like a strange six-sided table in the center of the room, its surface covered in what appeared to be random junk including a Casio™ synthesizer keyboard, a Speak & Spell™ toy, and an old Commodore VIC-20™ home computer (with no monitor or television attached to act as a screen). In the center of it all was a strange column of what looked like metal pipes and fluorescent light tubes that would light up and move up and down when the TARDIS was in flight.
Beyond the Control Room the hallways had the superficial appearance of halls in a school, very much like those of Centennial High School. The floor looksedlike it was covered in vinyl tiles dirtied by the footsteps of hundreds of sneakers, the walls were a drab faded neutral greenish-beige color, and the doors were mostly a faded wood color with frosted windows set in the top. Early on the travelers discovered several sets of rooms that were laid out like dormitories, small rooms with two single beds, some closet space and a pair of identical study desks. The rooms were lit by what looked like a pair of table lamps but on closer inspection the lamps were fixed to the desks and, despite casting light like a normal light, they did not appear to be plugged into anything.
Beyond the dorm rooms, from which each person selected one as their own and marked the door accordingly, the group found several other kinds of rooms. One room had the appearance of a school nurse's office, with a small examination table and a cabinet with bandages, over the counter pain killers, and other sundry medical supplies. There were washrooms marked as Boys and Girls, just like in a school, and shower facilities like those attached to a school gym. Another room had the look of a school cafeteria, with tables and chairs as well as an industrial style kitchen attached to it. There was a large stove, a fridge, and a sink as well as a large freezer chest in addition to many drawers and shelves. There were cutlery, bowls, plates and glasses in the cupboards and drawers along with basic cleaning supplies, wash clothes and dish towels. Some of the shelves were replete with boxes of cereal, all types and brands that were common in the 1970s and 80s. There were also boxes of crackers and cans of basic types of soup, again of brands common to the 70s and 80s. The freezer seemed to be completely full of frozen meals, mostly TV dinners. The fridge had drinks, but again mostly colas and other soda pop in cans and some juice boxes, all also appearing to be brands from the 70s and 80s.
Further exploration revealed a library, again having the outward appearance at least of a typical high school library, though some of the titles seemed strange. One particularly large room was a bit more unusual, it had multiple levels and the walls on every level were lined with what look like school lockers. Inside the lockers were not schoolbooks but clothes, and searching through the lockers revealed just about every kind clothing imaginable. The TARDIS even had an indoor swimming pool and, more bizarrely, what looked like outdoor tennis courts, though the outdoor aspect of a sky overhead and surrounding woodland turned out to be a highly convincing illusion.
When the group first entered the TARDIS after it had rebuilt itself in 1864 they found the interior of the door reflecting the mirror image of the front display of the cola machine facade, casting a red and white glow down a short corridor to the control room. The control room had gone full Steampunk: circular, with ornate metal arches converging at the center of the ceiling above the control console. The walls were decorated with riveted metal hexagons, with bronze circles in the center. The console was sharp-edged and six-sided, each panel a dark wood shade with brass borders, with completely different controls than had been present before: analog pressure gauges; multiple toggles, switches and levers; blinking lights, something resembling the thing that sets the speed on a steamship bridge; a Victorian typewriter; a tickertape machine (like the old time stock tickers); and something that looked like a vintage round shaving mirror but instead of reflecting it displayed what looked like an outer space scene. The central column was a transparent tube reaching to the ceiling where the arches converged; inside it was a massive Jacob's Ladder sending arcs of electricity up to what looked like a glowing blue orrery. The console sat on a raised platform with brass railings and the floor was a mix of metal grating and solid metal tiles. Some floor tiles had ornate grates that lit the room with an orange glow. On the opposite side of the control room from the entrance was a massive metal, grated spiral staircase leading up and down. A pair of scarlet wing-armed Victorian couches provided a place to lounge in the control room. The interior hallways reflected the control room decor - metal floor and walls with evenly spaced ornate arches and ornate grates in the floor illuminating the surroundings with the orange glow; like a steampunk seagoing vessel. Even the rooms had changed; the cafeteria replaced with an opulent dining hall, equipped with dumb waiters that seemed to produce whatever food was desired; the school nurse station replaced by a Victorian steamship doctor's office; individual bedrooms looked like steamship staterooms; the school library was now a Victorian gentleman's study/Oxford-style library with wood paneling, padded leather chairs, study desks with green-shaded lamps, and bookcases that seemed to go on forever (and that had those ladders on wheels). The books, no matter what title, were all leather bound (even the Danielle Steel novels and Dick & Jane books).
After the TARDIS was reanimated by releasing the Professor's essence from the Chameleon Arch into the central Console the interior of the craft once again took on a school-inspired aesthetic. This time around the floor was a checkerboard of black and white tiles and the walls smooth with an off-white and pale blue color tint. The Control Console had a retro-futuristic look, covered in push buttons, toggle switches, multi-colored lights and LED displays. Dominating one of the six panels was an early 1980s-style computer console with a clunky keyboard and a black-and-green monochrome monitor. The central column resembled a Lava Lamp, a glowing blue tube with faintly glowing blobs that would rise and fall through the interior. Several chalkboards decorated the walls of the Control Room around the Console, and to one side was a cart holding a 1980s CRT television set and what appeared to be a Betamax video cassette player, which served to display the external view of the sensors.
The hallways echoed the tiled floor and wall colors of the Control Room. Other changes also brought the interior look closer to what it had been when the time travelers first started using the TARDIS. Living quarters had reverted to a dormitory-style appearance, the library once again resembled one from a 1980s high school, and the dining area was laid out like a school cafeteria, this time with a buffet style service area that seems to sense what the diner wants and provides a matching selection (including a soda fountain drink dispenser that provides just about any potable liquid one can think of, other than alcoholic ones which it seems to only provide a simulated version of). The swimming pool and other athletic facilities also looked like they were based the style found in public schools.
Despite years of using the TARDIS the travelers are still discovering new rooms and functions. For example, they were completely unaware there was a secondary Control Room until they were shown it by the Weaver.
A TARDIS is secured by an isomorphic lock that requires a special key to open. A TARDIS key can take on many different appearances. Often the key will take a shape that is reflective of the outer appearance of the TARDIS as set by the ship's chameleon circuit, though not always. In the case of the Professor's TARDIS, when the chameleon circuit adopted the appearance of a cola vending machine the key took the form of a coin and has remained in this form ever since.
The key's current form is a metallic coin, approximately three centimetres across, with markings on both faces. The travelers did recognize any of the markings at first, but have since learned that one face of the coin shows the Mark of Rassilon, a symbol of the Time Lords, while the other face has something written in the circular, pseudo-clockwork Gallifreyan script (though they do not know what this says). For most of their adventures the travelers only had one key, having found the coin tucked away in a teacher's copy of Shakespeare's King Lear in the Professor's classroom and usually held by Zehra. After the TARDIS was restored with the Professor's essence it materialized enough new coins for all the travelers to have their own.
The travelers would gain access to the TARDIS by inserting the key coin in the coin slot of the cola machine outer shell. When they did this the front of the cola machine would unlock and they could swing it open and step in. The key would then drop into the coin return receptacle so the travelers could retrieve it before they went inside, but they could also access the receptacle from the inner side and retrieve the coin after closing the door.
A Chameleon Arch is a device that is apparently standard equipment on a TARDIS. The Chameleon Arch is capable of rewriting the biology of a Time Lord to transform them into another species, complete with an alternate identity as a member of that species imprinted on the Time Lord's mind. The Time Lord's true self, their memories and essence for lack of a better explanation, is stored in a receptacle. The subject forgets their true identity and life as a Time Lord and believes themself to be the new identity. A perception filter hides the receptacle's true nature from the Time Lord, though they are usually compelled to keep it near them. In some cases the Time Lord will give the receptacle over to someone they trust to keep it safe. By opening the receptacle and exposing themself to the vortex energies stored within the Time Lord is restored to their true biology and identity.
The Professor used his TARDIS' Chameleon Arch in 1975 to transform himself into the high school English teacher Richard Browning. His receptacle took the form of a common watch, which would change form over the years to reflect current fashion trends. By 1986 the watch had taken the form of a Swatch Watch. The time travelers found the Watch in 2017, hidden in a locker room. Zehra kept the watch with her, sensing it was somehow important. Unknown to Zehra, carrying the Watch allowed the receptacle's perception filter to disguise her own true nature as a Janus; cursory scans and observation would show her as a Human. The travelers discovered that by working together they could form a mental link with the essence of the Professor stored in the Watch. They could interact with him and on one occasion actually formed a gestalt consciousness with the Professor in control. The group could only maintain this for a short time without risking permanent brain damage so they did not do so very often.
When the travelers were trapped in 1986 they sought out the Professor in his human guise and Zehra inadvertently exposed him to the future version of the Watch that he was wearing. This released the Professor's essence and restored him to his true Time Lord self. In order to maintain the timeline he gave Zehra the Watch he was wearing, that still contained his essence, and made her secrete it in the hiding place where they would find it in 2017. When the Professor returned to 1986 after helping the group retrieve their version of his TARDIS he again used the Chameleon Arch to transform himself into the human Richard Browning. This time the receptacle took the form of a Sony Walkman and the Professor entrusted it to the safekeeping of Ems. After the Professor was killed by the Shadow Hunter while still in his human form Ems gave the receptacle to Zehra. When their TARDIS was drained by a Weeping Angel, the group were able to revive it by releasing the Professor's essence from the Walkman and letting it inhabit the TARDIS.
When the TARDIS crash landed in 1860s San Francisco it was badly damaged and so were many items inside, including Eileen's beloved bass guitar. When the TARDIS had completed repairing itself, adopting a Victorian Steampunk theme throughout, it also rebuilt the guitar along the same lines. Not only did the rebuilt bass guitar now look Steampunk, but it had also been enhanced with Time Lord sonic technology. Unfortunately, Eileen knew nothing about Gallifreyan sonic technology and had to rely on trial and error to discover any of the guitar's new capabilities. The first thing Eileen discovered was fairly obvious; the bass guitar no longer needed to be plugged into an amp to play, it seemed to be its own amplifier. She soon also learned that the guitar could produce disruptive effects that she could use to interfere with or block some signals. Eileen's success with the guitar was mostly haphazard at first; she would play around with the controls and hoped the sonic emissions she produced would have some, or any, kind of useful effect; but when she did stumble on a useful function she would make an effort to remember the settings that got her there. Eileen realizes that she has only scratched the surface of the guitar's capabilities. The latest trick she has learned was shown to her by the Weaver; how to use the sonic to open all kinds of locks.
The Stasis Gun, or Stasis Field Generator, is a gun that freezes its target in time. It's got a limited area of effect, but can freeze everything within a few metres of a designated point. So, aim it at a bunch of soldiers, pull the trigger, and they're frozen forever. Well, as long as the weapon's batteries last or until it's fired again. The time travelers found a Stasis Gun aboard Anomaly IV, the name given to what turned out to be a decaying TARDIS. They took the Stasis Gun with them, keeping it in reserve just in case they ever needed it, knowing it was essentially a one-shot weapon. Maryanne used the gun to freeze the Shadow Hunter in time at Centennial High School in 1986, ensuring it would remain trapped there until the charge wore off (which they knew from past experience would happen in 2017).