Another cause of change, one less noticeable but fundamental, is the modern growth of population closely connected with scientific and medical discoveries. It is interesting that the United Nations has set up a special Commission to study this question.
If I could be lucky enough to just have radio as the base for the rest of my life, I could build off that. No matter how successful I become, I always look at radio as the only skill set I can really call on. I even know how to operate the boards.