Stanford Research Systems RGA100, Operating Manual And Programming Reference

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Head Calibration and Security 5-23
SRS Residual Gas Analyzer
To change the CEM Gain do the following:
1. Connect to an RGA Head with a CEM option (Utilities menu).
2. Select the CEM Settings command form the Head menu.
3. Enter the desired gain in the Gain edit box.
4. Press the Adjust button and wait for the procedure to finish.
5. Press OK.
Peak Tuning the RGA Head
WARNING!
The peak tuning procedure should be performed by qualified personnel only. A
mistuned RGA Head could give erroneous readings.
Please refer to the RGA Tuning chapter of this manual for more information about
tuning and calibration.
All the variables displayed are initially read from the SRS RGA Head when the dialog
box is activated. When you are done with this procedure, the new parameters are stored
in non-volatile memory in the RGA Head.
Activating this dialog box automatically puts the display mode in Dual Analog mode.
The span is set to 10 amu with the two peak tuning gas masses set in the middle of each
span. If you press Scan and you have sufficient gas amounts of each peak tuning gas,
you should see the two peaks on the graphs. Use these peak for width and position
adjustments.
Every time you make a change to any of the parameters, press the Scan button to see the
effect of the change on the graph. Use the graph scaling command AutoScale to scale the
data.
The peak tuning procedure must be performed in the order described below. You may
repeat the entire procedure as needed until you are satisfied with the results.
To tune the RGA Head peaks do the following:
1. Select the two gases you are going to use for peak tuning. Use the Gas Selection
command (Head Menu)to enter the gas names and masses.
2. Press Scan to see where the peaks are positioned. Rescale the graph as needed so
you can see the gas peaks.
3. Enter a Position Shift value for the Low Mass Peak if the peak does not fall exactly
at its required mass. Press Scan. Repeat this step as needed until the peak is at the
correct mass.