The group is illustrated as follows:
Figure 2-9. PE5 Complex Working.
8. This is neither complex sending nor complex receiving. With so many different frequencies
used in no apparent system, it must be termed "complex working." If this is not clear, please
return to page 2-4 and review. If you understand the difference between complex working and
complex sending or complex receiving, continue with the instruction.
9. Although two stations on a link employing complex working would normally work in
alteration, one active at a time, it is sometimes the practice when a large volume of traffic is to
be passed to use DUPLEX OPERATION. In duplex operation, communication is carried on
simultaneously in both directions (on two frequencies) with both sending and receiving
operator at each station.
The figure 2-10 illustrates a link using duplex operation.
Figure 2-10. Duplex Operation.