Programmable Multi-Timer for TRU Waste Analysis Applications

A programmable, multiple-function timing module has been developed for use in transuranic (TRU) waste analysis applications at the Idaho National Engineering Laboratory. The Programmable Multi-Timer (PRMT) is an expanded version of a module originally built for accelerator-based active photon interrogation experiments. During the course of the experiments, it became obvious that a more versatile timer was needed to meet several unforeseen requirements. The PRMT was designed to meet the new requirements and to serve as a general-purpose timing module for other applications. For photon interrogation, two independent timing gates (Tl and T2) of variable width and delay are required. The gates are used to seperate induced prompt and delayed photofission neutrons that occur after an accelerator injection pulse. The Tl/T2 circuits are triggered ON by the application of an externally applied trigger pulse from the accelerator. The Tl and T2 gating pulses are generated at the end of user-programmed delays after the trigger pulse. In addition to the external trigger capability, the PRMT has been designed to trigger the T1/T2 circuits from a variable, internal, periodic source. Delay times and pulse widths are variable from 0 to 999 × 107 microseconds. A 24-hour time-of-day (TOD) clock has been included in the PRMT. The PRMT has the capability of generating two independent timing gates based on time-of day requirements. Two variable general-purpose reference frequency outputs are also available from the TOD clock.