Sierra Video ADA-108 - Manual (Page 14)

SIERRA VIDEO
8
OG-ADA-22
The OG-ADA-22 is built to accept two DA boards.
With this I/O module each DA only has 5 BNCs available on it. Only four outputs are
available and the input must be internally terminated in 75 ohms using the P1 jumper
near the connector end of the DA. This jumper must be set to ON.
Note:
If the OG-ADA-108 module is installed in a 20 slot frame using the OG-ADA-22 I/O module and
you do not have the termination set correctly the PWR LED and the board status indicator on
Dashboard will be yellow.
Dashboard will also display the state of the termination Jumper.
Video Connections
OG-ADA-10 and OG-ADA-21
There are two BNC connectors associated with the input of each video module. This is
called a “looping” input. This allows a signal connected to one of these connectors to be
available on the second connector.
Note:
If the second connector is unused it must be terminated with 75 ohms with either a 75ohm
terminator or the jumper P1 placed in the ON configuration.
Factory default for jumper P1 is OFF.
OG-ADA-22
The OG-ADA-22 is built to accept two DA boards.
When the OG-ADA-22 is used then only four outputs are available and the input must be
internally terminated in 75 ohms using the P1 jumper near the connector end of the DA.
This jumper must be set to ON for 20 slot frames.
Video system interconnects are made by using 75 ohm transmission lines (coax cable).
The device driving the line has a “source” impedance of 75 ohms, the cable has a 75
ohm impedance and the end of the interconnect must be terminated with 75 ohms (see
note above).
The accuracy of the termination affects signal level. Use either a 1% or 0.1% termination.
Unused amplifier positions do not need a termination.
Only the outputs which are used need to be terminated.