Note
When using the automatic RESET inhibit mode, the system inhibit is the time
interval automatically generated by the 9660 “OR” the external inhibit dura-
tion which ever lasts longer. For proper operation set the preamp inhibit time
to minimum or it can override the optimum inhibit time generated by the
9660.
When setting the inhibit time manually, set the TRP Inhibit to NORMAL. The TRP
Inhibit mode is selected in the Gain Device Adjust screen. The inhibit time of the
preamp must now be manually adjusted to encompass or extend to the point where the
trapezoid signal returns back to the baseline.
Using a “Tee” connector, connect the preamp’s Inhibit signal to the INHIBIT BNC
connector located on the rear panel of the 9660. Monitor the preamp’s Inhibit signal
and the 9660s Trapezoid signal, viewed on the Monitor Output, using an oscilloscope.
Use a clamp box, such as the Canberra Model LB1502, when viewing the Trapezoid
signal to prevent scope overload. Trigger the Oscilloscope on the leading edge of the
preamp Inhibit signal. Adjust the preamp inhibit time so that it returns to zero volts af-
ter the negative Trapezoid (negative overload) signal returns to the baseline (see Fig-
ure 36). Consult the Detector/Preamp Operator manual for this adjustment.
Appendix B - Performance Adjustments
74
Model 9660-9660A ICB Digital Signal Processor
Figure 35 Monitor Output, TRP Output, TRP Inhibit