Command State 92357-93023

The above diagrams represent the P/E, RNG, and PEN logic during a test with all guard vetoes disabled. The equations for P/E, RNG, and PEN events are:

Event type	Coincidence equation
P, E	P1.P2.P4*
RNG	P1.P2.P4
PEN	P1.P2.P8

The buffers into which "orderly" events can fall are as follows:

Range	No guards triggered	Low, not high guard triggered	High guard triggered
P1	NONE	NONE	NONE
P1 through P2	P/E	P/E	P/E
P1 through P3	P/E	P/E	P/E
P1 through P4, P5, P6, or P7	RNG	RNG	RNG
P1 through P8	RNG, PEN	RNG, PEN	RNG, PEN

In order to test whether the P3 center/guard crosstalk problem could cause the high guard threshold to trigger as well as the low guard threshold, all guard vetoes were removed from the P, E, RNG, and PEN equations. This was not the case, so PET was returned to the previous state for most of 1993. Note that this period, however, is the only time before the current command state was implemented when a penetrating event that triggered a guard threshold would be handled in an unbiased manner, such that it would be counted in the PEN rate if and only if it was eligible for output as a PHA event (in the state implemented on 99014, the reverse bias is applied, and the PEN rate rejects more events than the buffers).

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new 6 August 1999, revised 30 April 2000