You wrote that you have set HRD to Comm 1. What is "Comm 1" - I suppose you mean Windows' port COM1. Have you checked that the cable from the RRC to the PC actually is connected to the PC port COM1 and not COM2, or COM13, or something else (Using USB-to-Serial converters, e.g., give seemingly random COM port numbers)?
That is the first step to check.
I assume that the "DB9 cable" is a fully wired cable.
(The next step is to check the RTS/CTS settings, but the COM port setting in HRD should be double-checked first)
/Uno