Hi Kenny,
It's always great to hear you calling CQ on 160m most nights!
To start, I tune my elements for resonance quite high in frequency, well above
my design frequency.
On 160m, that is way up above 2 Mhz. That way, its easy to "fine tune" them
with some inductance at the base to lower the resonance as needed.
As explained in my video, the FIRST thing is to adjust the parasitic (or both
parasitics if a 3 el array) to set the resistance dip where you want it as
described in the video.
The resistance dip you are looking at is from the analyzer connected to the
DRIVER. You are adjusting the resonance on the parasitic, but observing the
change with the analyzer connected to the driver. Does that make sense?
The LAST thing to do is to match the driver on the design frequency.
For a parasitic array the DRIVEN element is completely irrelevant as far as
gain and F/B pattern are concerned.
Forget the driver tuning until the parasitics are tuned properly.
The gain and F/B pattern of your antenna is set ONLY by the tuning of the
parasitic elements.
When I say, "fine tune the parasitics", I mean, FINE tune!!! Those parasitics
need to be EXACTLY tuned to achieve the gain and F/B you expect from your model.
Using the method I explain allows you to do that.
Steve, ve6wz
> On Nov 29, 2024, at 3:43 PM, Kenny Silverman <kenny.k2kw@gmail.com> wrote:
>
> Hi Steve, as always, your tutorials are fantastic. Though this time I got a
> bit lost:
>
> Do you first tune the elements to the model frequencies and then tweak X and
> R?
>
> Regards , Kenny K2KW
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