Extron electronic 12800 manual Changing the syync termination

Upgrades and Maintenance, cont’d

Changing the syync termination

In a sync BME, the first eight physical inputs on each I/O card are equipped with sync termination DIP switches. Each switch provides the option of selecting either 510 ohms or 75 ohms.

Change the sync termination of the sync I/O card as follows:

1.	If changing the configuration of an installed card, open and remove the front
	door.
2.	On the I/O cardcage door, turn the left and right knurled knobs ¼-turn
	counterclockwise. Lower the door.

CDo not touch the electronic components or the connectors on the backplane or on the circuit cards without being electrically grounded. Handle circuit cards by their edges only. ESD can damage ICs, even if you cannot feel, see, or hear it.

3. Select the correct input card and the sync termination DIP switch specific for the input to change (figure 6-10). Rock the DIP to the rear for 75-ohm termination (the default setting). Rock the switch to the front for 510-ohm termination.

NAll input numbers identified in figure 6-10 are physical inputs.

1 2 3 4 5 6 7 8

Switch

1

2

3

4

5

6

7DIP

8Switches

DIP	Input	Input	Input	Input
switch	card 1	card 2	card 3	card 4
1	Input 1	Input 33	Input 65	Input 97
2	Input 2	Input 34	Input 66	Input 98
3	Input 3	Input 35	Input 67	Input 99
4	Input 4	Input 36	Input 68	Input 100
5	Input 5	Input 37	Input 69	Input 101
6	Input 6	Input 38	Input 70	Input 102
7	Input 7	Input 39	Input 71	Input 103
8	Input 8	Input 40	Input 72	Input 104

Figure 6-10 — Sync termination DIP switch

4.	Raise the I/O cardcage door to vertical and turn the left and right knurled
	knobs ¼-turn clockwise.
5.	Close the front door.

6-12 Matrix 12800 Switchers • Upgrades and Maintenance