I had the W9INN dipole for 40/80/160 with two sets of coils. The bandwidth
on 80 and 160 was about 30 khz. Compared to a ladder line fed 80m dipole,
the W9INN dipole was so much down on 80 and 160 that it was useless.
I ran some simulation of the W9INN dipole with one coil. The resistance at
resonance is 15 ohms while the dipole had very low swr at resonance
indicating the actual resistance close to 50 ohms. So large losses.
Ignacy NO9E
On Mon, Jan 2, 2023 at 12:53 PM jcjacobsen via TowerTalk <
towertalk@contesting.com> wrote:
> John, KK9A wrote:
>
> Jim, are these fan dipoles? I am not understanding how a loading coils
> will
> make a dipole work on two bands.
>
> John KK9A
>
>
> John and others:
>
>
> I've made MANY wire antennas using coils. In simple terms (which I can
> understand) what happens is, say an 80/40 dipole, the coils is made/wound
> with enough turns so on 40 it has a high enough inductive reactance to
> block rf flow any father. On 80 the coil acts as a plain load coil
>
>
> W9INN used these properties on his wire antennas, even multi band (more
> than 2 bands). Yes bandwidth suffers on lower bands, but that's what they
> make antenna "tuners" for.
>
>
> I believe Butternut uses something similar on their HF6/9V, HF2V, and with
> the 160 kit for same.
>
>
> Hope this helps.
> 73 and stay well
> K9WN Jake
>
>
> PS: NOT an antenna Guru. Much to old for heavy thoughts like this.
> _______________________________________________
>
>
>
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