Chapter 3. Installation
77
Strobe Units
The Lower Strobe Unit (P/N 30307-104A) provides strobe timing information for 8-slot shelves,
12-slot shelves, and the lower 12 card slots in a 24-card slot shelf.
The Lower Strobe Unit has eight active option switches (Figure 3-18), any of which can be set for
one of the eight preconfigured maps. (See Appendix D. Preconfigured Maps.) Select a
preconfigured map if there is not a control terminal available for software configuration of the D/I
Mux III.
The Upper Strobe Unit (P/N 30307-103) provides strobe timing information for the upper 12 card
slots in a 24-slot shelf. The Upper Strobe switches are ignored. Refer to Figure 3-18 for
depictions of the Upper and Lower Strobe Units.
In an emergency, an Upper Strobe unit can be converted to a Lower Strobe unit by removing the
W1 jumper. A Lower Strobe can be converted into an Upper Strobe by adding the W1 jumper.
Figure 3-24. Strobe Units (Front and Side Views)
P/N 30307-103 and 30307-104A