Once an RF signal enters an antenna and gets transformed into a current, it needs to get around, moving from component to component. I have called this thing which carries the current a conductor, but there are several media used in the RF world to get a signal from one point to another in a receiver or in a transmitter. These media, represented by the straight lines in any RF block diagram or schematic, fall into one of three categories: cables, waveguides, and circuit traces.
One way RF signals move around is through cables. The cable hooked up to the back of a VCR is an example of an RF cable, albeit an inexpensive one. RF cables are known as coaxial cables, which is a fancy way of saying that there ...