Total posts : 45366
I understood the written description of the proposed antenna exactly like the diagram shows. Remember that an ideal voltage source, by definition, has zero internal resistance. A real voltage source has finite internal resistance, of course, but it is convenient to simplify a discussion about antenna theory by assuming ideal conditions.
If the voltage source is moved from its assumed position at the top of the antenna to the bottom of the ground wire, the rules in circuit theory governing superposition require a short circuit at the top of the antenna. If the voltage source is at the bottom of the ground wire, the antenna is of a well-known type, as I pointed out in my previous post. If the radius of the pipe is small, like is assumed in the description, the antenna with the voltage source at the bottom of the ground wire will work about the same as an ordinary monopole with the same dimensions. However, if the voltage source is at the top, as was originally proposed, the radiation resistance will be very low, and this design will work very poorly. However, if the diameter of the pipe is made large (like a meter or more), the antenna will work about the same as an ordinary monopole the same height. So, this particular antenna design will not work well when the pipe diameter is small, and it has no performance advantages over an ordinary monopole the same height if the diameter is large. Of course, if the pipe diameter is in the order of a meter, or so, something like a screen mesh, or several vertical wires suspended in a circle, would be used; not a solid pipe.