FAST ComTec MCA4A, User Manual

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Installation procedure
To visualize the timing relationship a spectrum is defined that shows the arrival time on the x-axis, the ADC
pulse height on the y-axis and the count rate in z-direction (ref. Fig. 2.34). Also a one dimensional spectrum
is defined (set ADC range to 1) to show just a time spectrum (projection onto the x-axis).
In Fig. 2.33 the resulting spectra can be seen. Watching the map display (window (4)) amplitude variations
show up as vertical lines whereas delay time variations result in horizontal lines. Window (6) is the
corresponding three-dimensional view, window (5) the pulse height analysis and (3) the time spectrum. The
acquisition will not start before a trigger signal is sent to the TRG connector at the rear panel. The Real timer
is reset by each new signal there, so the real time cannot longer be used for normalizing. The system time,
computer run time and live time may be used instead of it. The trigger signal should be a short pulse. For
high polarity, the RTC is stopped and hold at zero as long as the signal level is high, and the acquisition is
inhibited. After the pulse the acquisition is running for the time the signal level remains low.
2.6 Installing more than one MCA4A Module
The software is able to operate up to 6 MCA4A modules with a single computer. Just connect them at an
USB port, switch on the power, and install the driver when you are prompted. When starting the software,
you will be asked to edit the MCA4.INI file as more than one MCA4A modules are found, and the notepad
editor will be automatically started with MCA4.INI loaded. Edit the line "devices=1" accordingly and save the
file.
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Fig. 2.34: RTC Spectrum Definition
Fig. 2.33: Basic Time Spectra