Application 1 

Radio signals from the SST transmitter are sent to the RDU-1 receiver, which is connected the JU-7 wiring junction which can be up to 200 feet from the WZ-PD. 

Application 2

The SST transmitter sends radio signals to a RDU-1 receiver connected to the HUB-1 multiplexer, which can be up to 2000 feet from the WZ-PD processor.