Canberra Lynx DSA, Руководство пользователя

Страница: 147 / 235

Programmable Controls
Lynx DSA User's Manual - 9240227J 137
HV
Green LED that indicates the state of the selected high voltage power supply:
•
Off
– High voltage supply is off.
•
Green Steady On – High voltage supply is ON and has reached its
programmed voltage.
• Red steady On – High voltage power supply detected fault condition. High
voltage output has been ramped to zero volts. Requires clearing the cause and
issue reset-fault command to unlatch before high voltage power supply can
be turned on.
ICR
Green LED that illuminates each time the instrument processes a nuclear event. The
intensity of the LED will vary in proportion to the incoming count rate.
Programmable Controls
Gain
The combination of Coarse Gain and Fine Gain set the overall system gain to match
the requirements of the detector and energy range for the application; overall gain is
continuously adjustable from x1.6 to x516.3 based on a 2 V full scale. Upper gain
adjustment is comparable to a x2581.5 setting on a traditional analog amplifier with
10 V full scale.
COARSE GAIN
Range is x2 to x430 in 19% increments.
FINE GAIN
Range is x0.8 to x1.2 in approximately 0.001% increments.
GAIN ATTENUATOR
ON/OFF; When ON (selected) enables a divide by four input attenuator to
minimize overload due to preamp signals with large dc offsets and Reset
Preamps with large output ramp dynamic range. When OFF is selected the signal
attenuation is removed.
CONVERSION GAIN
Selections of 256, 512, 1024, 2048, 4096, 8192, 16384 or 32768 channels defines
the size of the spectrum and resolution of the digitized PHA signal. Support for
two memory groups of equal in size to the Conversion Gain setting. Conversion
gain is set automatically through Input Size setting. In PHA, DLFC, and MSS
the Input Size also determines the size of the PHA spectrum in channels.