Automatic Inhibit Mode
Lynx DSA User's Manual - 9240227J
199
Using the Reset Input and Inhibit Function
During the preamp reset interval, the preamp reset event produces a large signal,
driving the Lynx into severe overload. The Lynx automatically senses reset events
and gates off pulse processing during the associated overload event. However, to
obtain optimum performance, especially at high count rates, it is recommended that
the preamplifier’s Inhibit signal be connected to the Reset Inhibit input on the Lynx
and the Inhibit Polarity be set appropriately. The figure shows a representation of the
Trapezoid signal at the output of the digital filter, as well as the Preamp Output and
Inhibit signals.
Figure 106: Monitor Output, TRP Output, TRP Inhibit
The Lynx system inhibit is initiated or derived from the Inhibit signal generated by
the Reset Preamp. The optimum system inhibit time can be set automatically by the
Lynx, or adjusted manually using the TRP Inhibit adjustments located on the fourth
page of the
MCA | Adjust | Gain
screen in the Acquisition and Analysis window.
Automatic Inhibit Mode
For automatic inhibit, set the Inhibit Mode to Auto; this is the default setting. When
using the Auto mode, the correct system inhibit time is automatically set. It is not
necessary to make critical adjustments of the inhibit signal at the preamp. However,
if the reset preamp is equipped with an adjustable inhibit signal pulse width, it should
be set to its minimum value. Please consult the Detector/Preamp Operator’s manual
for this adjustment.
Note: When using the Automatic Reset inhibit mode, the total system inhibit
duration is the time interval automatically generated by the Lynx “OR” the
external (preamp) inhibit duration, whichever lasts longer. For proper
automatic operation set the preamp inhibit time to minimum, or it can
override the optimum inhibit time generated by the Lynx.
