T-U

TBC (Time Base Corrector)

Multiplexers and quad splitters rely on a TBC circuit to align unsynchronized video signal before the signal processing begins.

Telephoto lens

a camera lens that magnifies the image.

Test Pattern Generator

When adjusting and testing a monitor, a test pattern generator is used to create a test pattern for the required visual feedback. This device can also create a test pattern that can be used to verify the integrity and possibly troubleshoot the source video signal.

Time lapse VCR

Used primarily by CCTV systems, this VCR enables increased recording time on a videocassette by not recording all the frames. But on receipt of an alarm can switch to real time mode.

Touch Screen

Advances in monitor technology have enabled touch sensitive monitors that can perform specific actions by responding to a user touching relevant screen areas.

Tracking

A zoom lens that can stay in focus while zooming from wide angle to telephoto position is said to be tracking.

UDP (User Datagram Protocol)

UDP is a communications protocol that makes possible the sending of datagram messages from one computer to an application in another computer. It's connectionless and suffers from unreliability, since it is unable to check for any errors in delivery. UDP is often a protocol used in video streaming because it ignores lost data and continues the live feed of information (this being preferable to the interruption of real-time data while attempting to retransmit lost data).

UPS (Uninterruptible Power Supply)

Justifiably popular with many electronics users, a UPS stores electricity in a battery and supplies power to a system (allowing a user to shut down w/out losing data or continue for a specific time period) during a power failure.

URL (Uniform Resource Locator)

The URL is the Internet address that a software browser requires in order to find that Internet resource.

UTP (Unshielded Twisted Pair)

This type of cable is used to transmit video signals across distances greater than a coaxial cable can handle. The RG59 standard of UTP cable is roughly 600 ft. In conjunction with video baluns, they can stretch over 1200 ft. for full colour video. UDP is cost effective too, mainly due to lower costs than coaxial cable, being easily terminated, and being capable to carrying data, video, and audio signals across the same cable with little interference.