Appendix

Glossary

Reference video signal

A video signal containing a sync signal or sync and burst signal, used as a reference for synchronizing video equipment.

Servolocking

The locking of the phase and speed of a VTR’s head drum rotation and tape transport to a reference signal during recording and playback.

Standby-off mode

A mode in which head drum rotation is stopped and tape tension is released, and thus the VTR is not ready for immediate recording and playback. This mode alleviates the tape and video heads from wear or damage.

Standby-on mode

A mode in which the head drum rotates with the tape wrapped around it, and thus the VTR is ready for immediate recording or playback. The VTR enters standby-off mode after remaining in standby-on mode for a specified length of time to prevent wear or damage to the tape and video heads.

Time code

A digital signal recorded on the video tape that supplies information such as hour, minute, second and frame number for each frame to facilitate the setting of edit points or searching for specific scenes on the tape. There are two types of time codes: SMPTE (for the NTSC color system) and EBU (for the PAL/SECAM color system); and two time code recording formats: longitudinal time code (LTC) and vertical time code (VITC).

Tracking

The synchronizing of the head drum rotation phase and tape transport phase during playback and recording. Tracking is adjusted to eliminate picture instability when playing back material recorded on another VTR.

Unloading

Also called “unthreading.” A process by which the VTR winds the tape back into the cassette case and ejects the cassette from the slot. Normally, the VTR automatically unloads the cassette when you press the EJECT button.

User bits

A recordable 32-bit section in each time code on a video tape for recording such information as the recording year, month, and day, and the tape or program ID number.

Vertical interval time code

See VITC.

VITC

Abbreviation for Vertical Interval Time Code. This is a time code recorded on a video signal track during the vertical blanking interval. It can be read correctly even during slow or still picture playback. See also LTC.

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