On 11/9/2010 9:38 PM, n8de@thepoint.net wrote:
> The gamma match itself is an inductor ... you can only cancel that
> inductance by putting a series capacitor inline with it. IF you do
> not, changing the length of the driven element will change the
> APPARENT impedance, but it will still have an inductive (reactive)
> component.
>
> 73
> Don
> N8DE
>
I have a couple of homebrew 4 el on 3/4 wavelength boom yagis with
gamma matches. The antennas were designed to have a -j component at the
feedpoint. Using a gamma match without a capacitor resulted in a
slightly inductive feedpoint impedance. After shortening each end of
the DE a 25 dB return loss was measured at the design frequency. No
inductive component.
73, Bob, W5AH
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