Thermo Scientific SGD-O, Руководство пользователя

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Adjusting the Gain Settings
Components and Jumpers
7-2
SGD-O User Guide Thermo Fisher Scientific
Figure 7–1. FSU pre-amp board components and gain jumpers
Caution
The C13 capacitor is located under the metal shield on the FSU
pre-amp board. Everything under this shield is high impedance circuitry.
Do not touch anything under the shield with bare hands! If any of these
components are contaminated, the detector signal will fluctuate, making
the detector ineffective. Use only clean metal tools to touch these
components. Do not apply any kind of cleaner to them.

For most applications, the value of the C13 capacitor is normally 330 pF.
However, as shown in Table 7–1 , the value of C13 can also be 220 pF or
470 pF, depending on the application for which the detector was originally
purchased. A 220 pF capacitor will make the gain higher and a 470 pF
capacitor will make the gain lower. If you are having trouble getting the
gain either high enough or low enough, check the value of C13.