Varian ProStar 325 UV-Vis, Руководство по обслуживанию

Страница: 137 / 149

ProStar325 Service Manual
Publication date 8 May 2003
137
7.10.4 Gain and Dark Tables
Gain Table - this displays each wavelength interval where a gain
calibration was performed, and shows the corresponding gain
stage used at that wavelength (as described in the Electronics
section).
This calibration is performed using the UV lamp source which
has a typical working range of 190 – 400nm. The gain stages
within this range should be quite low because the signal strength
is high. Above this range, the gain stages should increase as the
signal level decreases. Around 656nm the gain should decrease
again in the presence of the deuterium peak at 656.1nm. All this
should be reflected in the gain table data.
If the gain stages are all high across the entire range, then this
will indicate that a low, or possibly no signal, is reaching the
photodiodes.
You can download the CSV file of the gain table and plot it in a
graph and use it as part of troubleshooting.
Below is a typical plot from a working detector.
StockCheck.com