GBS Elektronik MCA 166 - Manual (Page 43)

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-To exit a menu use the “ESC” -key.
Step 4: Loading setup file
Navigate with the arrow keys to setup menu, press “Enter", goto “read setup file", press
“Enter”. Choose with the arrow keys sdp31060.spe, press “Enter”, “Enter”, “ESC”, ”ESC”.
All parameters can also be modified manually, they are: Detector high voltage: +300V /
Presets-Choice: None / MCA setup-channels: 1024 / -Treshold: 2 / -LLD: 0 / -ULD 991 / -
ADC Input: Amplifier / Amplifier setup-Coarse gain: 200 / -fine gain: 0.9100 / -Shaping
time(µs): 1 / -Input polarity: neg / Stabilization setup-Stabilization: off.
Step 5: Switching on high voltage
Choose “Detector high voltage setup” in the setup menu; behind high voltage should
appear +300. Press “ESC” and “Enter” to switch on high voltage. In the lowermost line on
the screen should appear now “HV = +300V”.
Step 6: starting measurement
Now choose Data acquisition - Measurement, press “Enter”. The acquisition screen
should appear. “F4” starts a measurement, “F5” stops it. During the measurement the
growing spectrum can be seen, also some additional parameters (e.g. elapsed time,
cursor position, actual count rate) are shown.
The arrow keys will move the cursor and change the vertical scale on this screen. When a
sufficient accurate spectrum is acquired, (maybe 300 s at 100 cps), stop by “F5”.
Step 7: Saving spectrum
Leave measurement screen with “ESC”, choose “File - Save”, press “Enter”. Now a file
menu should appear. Choose a filename like xxxxxxxx.spe and enter it in the line “File”.
Press “Enter” two times. Another box appears where you can enter a remark to the
spectrum. Exit this box with “ESC”. Press another time “ESC” to go back to the menus.
Step 8: Switching off
Choose “File - eXit”. Press “Enter”. Confirm “Turn off HV” - “yes” by pressing “Enter”.
Confirm “Don’t forget to turn off MMCA” by pressing “Enter”. Switch off MCA-166 and
Palmtop HP200LX. Now you can disconnect the cables.
3.10 Example for a Measurement with a HPGe Detector
Step 1: Connecting cables
The Palmtop 200 LX has to be connected by cable to the MCA 166, the HPGe detector S
with its 3 different connectors has also to be connected to the MCA 166. There may be a
fourth cable (HV inhibit), if so, use the HV inhibit adapter to connect it.
Step 2: Switching on
Switch on MCA, the green lamp should start to flash. Switch on Palmtop (the key in the
uppermost right edge, “ON”). A menu with options for different programs should appear.
(If not, try Ctrl-Alt-Del or Shift (yellow arrow)-Ctrl-ON).
Step 3: Starting program
Type “3” to start SPEC program. Answer “y” and “Enter” (The big key with the left arrow)
to the question ”Reset MMCA to SPEC defaults and clear all spectra (y/n) ?” .