Appendix: Adaptor Cable Drawings
The following section includes drawings for several
popular input and output adaptor cables. In each
case, the connector on one end is the 50-pin D-rib-
bon connector (Amphenol or equivalent), The
lengths of the adapters are not specified, but should
be selected to fit the installation or use.
CDP cables vary widely in the connector type and
wiring, and it is impossible here to include all the
possibilities. The general approach is to redraw the
CDP cable as a grouping of cables (as in Figure 6).
Then, find the connector pin numbers on the right
side (of the drawing) which go through the string to
the most distant takeout. This takeout is defmed at
ground station 1. The input adaptor will be wired to
connect these wires to pins 1 and 26 on the input
connector (for stations l-24 on the rollalong switch.
Likewise). Then, the second farthest station goes to
pins 2 and 27. The process continues until you have
used all the wires in the CDP cables to all the sta-
lions.
It is possible in some arrangements that additional
CDP cables will go off to the right. For example, if
you have 120 geophonc stations, you would probab-
ly have 60 (or 72) to the left, and 60 (or 48) to the
right. Use the principles developed here to con-
struct those adapters.
Page 8
RS-96/24 & RS-120/48
Geostuff
