Signal Input Connections - EDL Displays 6120 Operation And Maintenance Manual

SIGNAL INPUT CONNECTIONS

See Figure 5 for location of rear panel signal input connections.
The Model 6115, Model 6116 and 6119 Master Sync Monitors will automatically adapt to the
user's synchronization system format. Three formats are supported. These are:
1. Red, Green, Blue video signals with composite sync on green (three cable hookup).
2. Red, Green, Blue video signals with separate mixed sync signal (four cable hookup).
3. Red, Green Blue video signals with separate vertical and horizontal sync signals (five
cable hookup).
The video inputs may be adjusted to accommodate from 0.7 to 1.4 volts peak to peak video
signal levels. Any d.c. offset on the signal is eliminated by a.c. coupling and d.c. restoration at
the video amplifier during the back porch portion of the video signal.
The external sync inputs can accommodate from 1.0 to 4.0 volts peak to peak signals without
any adjustments. These inputs are a.c. coupled and d.c. restored by the monitor before
thresholding occurs. These inputs may be either positive or negative polarity and need not be
the same.
All five signal inputs may be switched from 75 Ohm to high impedance (20 kilohm) for "loop-
thru" operation. User-supplied BNC "T" adapters must be used to connect the additional
devices between the raster engine and the final device on the line. Because of the very high
performance of the devices involved, extreme care must be taken by following these
guidelines.
1. The raster engine must be at the beginning of the transmission line. BNC "T" adapters
must not be used at the raster engine.
2. All devices must be set for high impedance input except for the last device on the
transmission line.
3. The last device on the transmission line must have a 75 Ohm termination impedance
and not have BNC "T" adapters at its connectors unless used for the terminators.
4. All cables must be 75 Ohm impedance and as short as possible (for most signal
sources cable length should not exceed 10 feet).
NOTE: These aforementioned rules are not unique to the Model 6115, 6116 and 6 119
monitors. They must be followed to assure proper operation of these high performance
devices regardless of their manufacture.
6115 - 6120 Operation and Maintenance Manual ©EDL Displays, Inc. January 1997
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