National Instruments SCXI-1121 Manuel D’Utilisation
Chapter 2
Configuration and Installation
2-8
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Input Channel Jumpers
Gain Jumpers
Each input channel has two gain stages. The first gain stage provides gains
of 1, 10, 50, and 100 and the second stage provides gains of 1, 2, 5, 10, and
20. Tables 2-3 and 2-4 show how to set up the gain for each channel.
of 1, 10, 50, and 100 and the second stage provides gains of 1, 2, 5, 10, and
20. Tables 2-3 and 2-4 show how to set up the gain for each channel.
The board is shipped to you with the first-stage gain set to 100 (position A)
and a second-stage gain set to 10 (position D). To change the gain of your
module, move the appropriate jumper on your module to the position
indicated in Table 2-4. Refer to Figure 2-2 for the jumper locations on your
module.
and a second-stage gain set to 10 (position D). To change the gain of your
module, move the appropriate jumper on your module to the position
indicated in Table 2-4. Refer to Figure 2-2 for the jumper locations on your
module.
To determine the overall gain of a given channel use the following formula:
Overall gain = First-stage gain
×
second-stage gain
Table 2-3. Gain Jumper Allocation
Input Channel
Number
First Gain
Jumper
Second Gain
Jumper
0
W3
W4
1
W19
W20
2
W29
W30
3
W41
W42
Table 2-4. Gain Jumper Positions
Gain
Setting
Jumper Position
First-stage
1
10
50
50
100
D
C
B
B
A (factory setting)
Second-stage
1
2
5
2
5
10
20
20
A
B
C
C
D (factory setting)
E