Terminating Bnc Video Sync Distribution - Yamaha D24 Owner's Manual

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Chapter 13—Multiple D24s & Video Sync

Terminating BNC Video Sync Distribution

When a video sync signal is distributed via BNC cables, it must be terminated correctly.
Normally, termination is applied at the last device connected, although it depends on
the distribution method being used. The D24's VIDEO 75 ON/OFF switch allows the
D24 to be connected in a variety of ways. The following examples show three ways in
which a video sync signal can be distributed and how termination should be applied.
Video Sync Distribution Box
In this example, a dedicated video sync distribution box is used to supply a video sync
signal to each device individually. Termination is applied on each device.
Bus Distribution
In this example, the video sync signal is distributed via a common bus. Termination is
applied at the last device only.
Daisy Chain Distribution
In this example, the video sync signal is distributed in a daisy-chain fashion, with each
device feeding the video sync signal on to the next device. Termination is applied at the
last device only. This method of distribution is not recommended for larger systems.
D24—Owner's Manual
VIDEO OUT
Video sync
master
(BNC)
VIDEO IN (BNC) VIDEO IN (BNC)
Device-A Device-B
Termination = ON Termination = ON
Video sync slave Video sync slave
Video sync
master
VIDEO OUT (BNC)
VIDEO IN (BNC) VIDEO IN (BNC)
Device-A Device-B
Termination = ON Termination = ON
Video sync slave Video sync slave
Video sync
master
VIDEO OUT (BNC)
VIDEO IN VIDEO OUT
(BNC) (BNC)
Device-A
Termination = OFF
Video sync slave
Video sync
distribution box
VIDEO IN (BNC)
Device-C
Termination = ON
Video sync slave
VIDEO IN (BNC)
Device-C
Termination = ON
Video sync slave
VIDEO IN VIDEO OUT
(BNC) (BNC)
Device-B
Termination = OFF
Video sync slave
VIDEO IN (BNC)
Device-D
Termination = ON
Video sync slave
VIDEO IN (BNC)
Device-D
Termination = ON
Video sync slave
VIDEO IN
(BNC)
Device-C
Termination = ON
Video sync slave