bob and the gang,
inserted the 259 and with the 1:1 balun.
resonate freq is 2.487 or there abouts
so the antenna as it sits is too short.
I'll re-check the length with my harbor freight made in china 300 foot tape and
see what each leg is (length wise)
Mike Bryce, WB8VGE
the heathkit shop
SunLight energy systems
J e e p
o|||||||o
On Oct 12, 2013, at 10:42 AM, Bob McGraw - K4TAX wrote:
> The extra / external cap is used across the capacitor bank, starting at
> position #4 and #5. Both on the Low and High Z sides. I find the text is
> incorrect, the schematic is correct. Yes a .01 is way too much C by a factor
> of 10x.
>
> If you have a means to do so, what is the natural resonant frequency of the
> antenna? I use my MFJ-259 as a grid dip meter effect to find the resonant
> frequency. I'm not speaking of some frequency where the SWR is 1:1 or such.
>
> I take a different approach to antennas. I first start with a resonant
> antenna at the desired frequency, then adjust the height of the antenna to
> attain the desired feed point impedance. I saw Jim Brown, K9YC mentioned
> this in his earlier post as he used different coax impedance lines dependant
> on the height of the antenna. I am not one to "prune" the length of the
> antenna for some SWR value. Now in cases I know we can't get the antenna at
> different heights specially as we get to 160M and to some extent 80M. In
> these cases, the typical height above ground does bring the center Z to 20 to
> 30 ohms. Nothing wrong with this. With low loss coax or a balanced feed,
> just let the tuner deal with it. That's what it is supposed to do. I find
> having a resonant wire is more effective and easier to effect a good match.
>
> 73
> Bob, K4TAX
>
>
>
>
>
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