I'm Stuck.

Had the sim a few weeks now and have progressed onto the navigation instructions.  I'm confused and and a little frustrated about the lack of detail in the tutorial or help about the radio stack.  I want it to be "as real as it gets" so I want to be able to operate the radio stack - Tune into different frequencies, ID NDBs, and even just understand the workings of it etc, but I can't find any info/help on how to do this.  Any help would be much appreciated.

HB