Doesn't a dummy load work even better?
73
Bob K4TAX
Colin Lamb wrote:
>
> One way to prevent high voltage at the ends of an antenna is to reduce
> the Q. The easiest way to do this is to use a lossy wire for the
> antenna. This will also reduce the SWR variations as you change
> frequency.
>
> Galvanized Iron electric fence wire is cheap and reduces Q nicely.
> Since losses are high, it reduces noise pick up on receive -
> especially from stations a long distance away.
>
> For the ultimate in Q reduction, nichrome works very well. With at
> least a quarter wave of nichrome, the end insulators can be made
> of silver and they will not introduce appreciable losses.
>
> Lossy antennas eliminate the need for antenna tuners and eliminate the
> need to calculate 1/4 waves. They also allow you to tune up on the
> actual antenna without having to bother with the dummy load - a real
> boon to contest operators who like to tune up on frequency.
>
> For quiet reception, the ultimate antenna is created by removing the
> center conductor from 1/4 wave coax and replacing it with 1/4 wave of
> nichrome.
>
> The cubical quad was invented to eliminate corona effect of high power
> antennas. Beams and dipoles in the Andes had the corona effect and
> kept destroying themselves. Apparently the designer did not know
> about nichrome. Instead, he built a quad to eliminate ends of the
> antenna.
>
> Colin K7FM
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