MADE IN THE USA
A PRODUCT OF THE GENFLEX SYSTEM
LINK ELECTRONICS, INC.
DIGITAL SDI GEN-LOCK
812-OP/D
For Future Generations
The 812-OP/D accepts digital blackburst to gen-
lock to an external source
.
The genlock cell is slot
number two. All other modules lock to the 812-
OP/D. Whether module 812-OP/C or 812-OP/D, all
other modules lock to whatever in cell number two.
The number two module will produce the necessary
lock pulses for all of the other modules in the
chassis. The remaining four cell will accept a digital
or analog test of black module.
The 812-OP/D digital genlock module takes in a
stable digital black burst signal and genlocks to it.
This is accomplished by stripping horizontal sync
off of the in coming black burst signal and doing a
phase and frequency lock to a very stable 27 MHz
VCXO. The phase-lock-loop has a LED indicator
that signals green when horizontal lock is obtained
and signals red when no lock is obtained. The 27
MHZ signal, clocks a complex programmab
l
e logic
device that generates all the necessary pulses that
are needed for the rest of the modules. The pulses
are buffered and sent down the mother board buss.
This complex programmable
l
ogic device a
l
so takes
in stripped vertical sync and field identification
pulses and resets appropriate counters within the
device. This develops output pulses that are in
proper time and phase with incoming video.
The 812 OP/D digital genlock module also has a
video presence detector that controls if the module
is in genlock or free-run. A bicolor LED is used for
a video presence indicator, whenever video is
present the LED turns green and whenever there is
no video present the LED turns red. If there is no
video to the module, it then automatically switches
over to a free-run frequency condition and a front
panel control is used to adjust the dc volte of the
VCXO. This then changes the frequency of the 27
MHZ oscillator.
Reference source selection can be accomplished in
three ways:
1. No video, the module would automatically switch
over to its internal reference source.
2. Manually switching the front pane! switch
AUTO/INT over to its internal reference source.
3. Applying video and having the AUTO/INT switch
paced in the AUTO mode. The module is then
running in proper genlock mode.
Whenever, the 812 OP/D genlock module is placed
in its INT, internal reference source a front panel
yellow LED indicator lights up and the module is
free-running on its internal oscillator. Whenever, the
812 OP/C genlock module.
The PCO-818 automatic pulse change-over modules operate as independent or synchronized operation. Two
PCO-818 change-over chassis may be interlinked to cause all modules to switch should a failure occur in the
master generator.
LINK
ELECTRONICS, INC.
2137 Rust Avenue
Cape Girardeau, MO 63703-7668
Phone 573 334 4433
FAX 573 334 9255
