Last week, I wrote about the state of the art in radio: Software-defined radios, which use software to do the job that mechanical parts do in older radios. Most, if not all, modern designs incorporate ...

We had this old Zenith AM/FM radio back in the 1950s which looked just like this one. As a small child, I used to turn the tone control on the side up and down, over and over again as Mom listened to ...