Installation & Operation Manual TCC70XS
Page 60
4.1.2.4 Time Code and Video Locked to a Real
–Time Reference
If you are working with time code and video, the time code has to be locked to the video
signal. If the time code should transport the local time precisely, the time code generator
receives time & date from a real
–
time reference.
The video sync generator (SPG) has to be locked to the real
–
time reference in order to avoid
time jumps in the time code. If there is not such a lock mechanism installed, the SPG drifts
against the real
–
time and the time code drifts the same amount
–
because it is locked to the
video. After a certain time, the drift amounts to a whole frame and during the next update with
the real
–
time reference a time jump will occur.
The following installation avoids time jumps in a 625/50 (PAL) television system:
Receiver
GPS
O
ut
do
or
An
te
nn
a
10 MHz
PPS + TxD
SD/HD/3G
SPG
TCC70XS
A high
–
quality GPS receiver outputs a 10 MHz signal which synchronizes the SPG. TCC70XS
receives time & date as well as PPS from the GPS receiver, but the internal phase and
frequency synchronization locks to the connected video signal. All units are locked, no illegal
time jump will occur.