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Old May 1st 10, 02:10 PM posted to rec.radio.amateur.antenna
Wimpie[_2_] Wimpie[_2_] is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 329
Default Meandering Antenna

On 1 mayo, 02:25, "VK2KC" wrote:
I was wondering if anyone had any experience of the Meandering Antenna or
Meandering Dipole, I have found an article in Pat Hawkers book but the
drawings are a bit hard to understand.
I have limited space and was considering building one for 7.1 mhz

Thanks
John


Hello,

I assume that you talk about meandering like the zig/zag pattern on a
viper or the pattern of a sidewinder. At other frequencies, yes I do
have.

Meandering increases the inductance per unit of length, so the
propagating wave slows down. This results in a reduction of resonant
length.

The zig/zag wire pieces do, however, not contribute to the far field
radiation. Given the same feed current, the meandered dipole radiates
less then the full HW one, so the radiation resistance goes down.
When your dipole length is about half of the full size length, feed
point impedance goes down with almost factor 4.

When you experience good VSWR in a center fed short meandered dipole,
you can be sure to have losses.

Best regards,


Wim
PA3DJS
www.tetech.nl
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