[Elecraft] [k3] Isotropic Antenna

[Jim Brown]

This so-called "antenna" is at best dumb, and at worst a rip-off. As 
master antenna-designer N6BT wrote some years ago, "everything 'works,' 
even a light bulb." He demonstrated this by mounting a a light bulb on a 
wooden fencepost, feeding with coax that he had carefully choked so that 
the coax could not radiate, and working all continents with it.

As others have noted, antennas like magnetic loops, loaded whips 
(HamSticks, etc.), and long wires are the weapons of choice with limited 
space and/or requirements of minimal visibility. If the frame of the 
building is non-metallic, indoor antennas can work (but can also be 
mondo noisy on RX). If the frame is metallic, the antenna must be 
outside. The good news is that the building frame will work fine as a 
counterpoise (although it may block the antenna in the direction of the 
building).  A long wire launched away from the building is best -- small 
diameter enameled wire can be hard to see, and works fine as an antenna.

73, Jim K9YC

On Thu,4/7/2016 2:41 AM, Petr, OK1RP/M0SIS wrote:
> I am sure that David talked about an Isotron antennas like this:
> https://www.isotronantennas.com/
>
> I intensively tested/used this antenna in 90's on 40m (product from Sigi,
> DK9FN) and I have to say it is a nightmare in overall. From my own
> experiences the performance of this toy was highly dependent to the
> grounding availability, bandwidth was very small and tunning was influenced
> by ground only but also by closed objects a lot.