Connecting The Frame Genlock Reference; Figure 4-1: 7800Fr And 7800Fr-Q Rear Panel - evertz 7800 Manual

7800 MultiFrame Manual
7800FR 3 Rack Unit Frame
4.

CONNECTING THE FRAME GENLOCK REFERENCE

The 7800FR and 7800FR-Q frame versions have two input BNCs that can be used to deliver reference
signals to cards that are housed in the frame. These are labeled REF 1 and REF 2 and are located on the
rear of the frame in the bottom, left hand side (as facing the rear of the frame) near the GROC connector.
See Figure 4-1.

Figure 4-1: 7800FR and 7800FR-Q Rear Panel

The REF 1 and REF 2 inputs provide an analog connection to the modules in the frame and can carry a
wide variety of signals depending on the modules inserted into the frame. For example, NTSC, PAL-B,
Tri-level sync, bi-level sync, DARS, etc. is supported. Each card that supports a Frame reference will
have a control for selecting which of the references to use. See the specific module chapter for
information on the reference input operation and control. Because there are two frame reference inputs,
you can supply the frame with two completely different signals or two different time bases of the same type
of signal. It is up to the system designer/installer/operator to supply appropriate signals and configure
modules to use the correct reference input.
Both reference inputs are isolated from the frame and provide a balanced analog signal connection along
the module interconnect printed circuit board to all modules. The balanced signal is terminated at the far
end of the module interconnect bus with a 75 Ohm termination. Each installed module that supports the
use of these reference inputs will slightly degrade the return loss of the frame reference inputs (approx.
1dB per card). For this reason, it is important that the reference input signal comes directly from a
dedicated distribution source like a distribution amplifier without passing through any reference loops or
high impedance "T"' connections.
7800FR - 11
Revision 1.3