Environnement MIR 9000 - LCD, Technical Manual

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MIR 9000 Duplication prohibited
5–18
February 2000
- 5 volts
0 volt
5 volts
10 volts
15 volts
Saturation line
Figure 5.9 – Saturated signal Oscillogram
Using P3, adjust the largest signal 2 volts below the saturation line, namely at 12 volts.
0 v olt
2 v olts
4 v olts
6 v olts
8 v olts
10 v olts
12 v olts
Saturation line
Figure 5.10 – Correct signal Oscillogram
5.2.6.6 Automatic amplificatio
In the “Tests / Optical Bench” menu, read the value in points of the largest signal. The Auto Gain
variable corresponds to this value, rounding down the value to the next 10 000 place (for example, if
the largest signal is at 56800 points, it will take the value at 50 000 pts).
In the “Configuration / Software /Analyzer configuration” menu, adjust the Static Gain variable to 00
(validates the automatic gain). To work in automatic mode with the same gain of each signal, program
the
Auto Gain variable to the value shown above to which is added
1
( Auto Gain : 5000
1
in our
example). Start a Zero Ref.
Check the signals in Pt11 and Pt17.
If the signal appears saturated in Pt11 or Pt17, take up the fixed amplification again by reducing the
largest signal by 2 volts (signal at 10 volts).