Burst Electronics TC-3 - Manual (Page 3)

2 TC-3 SMPTE TIME CODE Generator/Reader
Introduction
The TC-3 is a SMPTE longitudinal time code generator/reader/re-
generator that uses the audio track (or special TC track if so
equipped), of a VCR, to record/read the time code. The TC-3 uses
the industry standard SMPTE time code format. Time code, read or
generated, is displayed in a “window” keyed over incoming video.
The TC-3 will read time code at play speed.
SMPTE Time Code
SMPTE time code is a standardized format for recording a unique
set of numbers on video tape for each video frame. For the TC-3
these numbers are recorded on the audio track of a VCR and incre-
ment for each frame of video. The time code format is standardized
in the United States by the Society of Motion Picture and Televi-
sion Engineers (SMPTE).
SMPTE time code is composed of two parts: the time code itself
and “user bits”.
The time code consists of hours, minutes, seconds, and frames.
NTSC video has approximately 30 frames of video per second. The
TC-3 accepts a video signal, and when in the generator mode, counts
frames. When 30 frames have been counted the TC-3 increments
the “seconds” count. When the “seconds” count passes 59, the min-
utes count is incremented and so on.
In the reader mode, the TC-3 reads the time code off from tape, and
displays it in a “window” keyed over incoming video.
The user bit portion of the time code is for storing any miscella-
neous information you may want to encode on tape. This informa-
tion could be most anything, such as the date when the tape was
shot, the camera number the tape came from, or even special infor-
mation other equipment might use (if this equipment has the ability
read user bits).