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Just for your information...
A dipole is commonly thought of as a 1/2 wave antenna fed in the center. If it's not a 1/2 wave length long, but still fed in the center, call it a doublet instead of a dipole. Just a difference in terminology, but it can sure clear up mistakes in what you are talking about.
There's no significant difference between the radiation pattern of a vertical dipole and an end fed 1/2 wave vertical antenna. The biggest differences between the two would be in how the input impedance is handled. That end fed 1/2 wave will have a very high impedance and is why the 'A99' uses a matching device at the input. That matching device is probably the biggest draw-back to them, it does have limited power handling ability. If the thing was center fed with no matching device used, that power handling ability would be much greater. That's not done all that often because mounting a center fed antenna isn't exactly as easy as an end fed one. Oh well...
The only significant difference between a 1/4 wave, 1/2 wave, or 5/8 wave vertical is in the shape of it's radiation pattern. None of them 'radiates' any more power than is fed to them, they just 'put' that power in different places. The total amount is still the same.
- 'Doc

<blockquote data-quote="W5LZ" data-source="post: 408717" data-attributes="member: 129">Just for your information...A dipole is commonly thought of as a 1/2 wave antenna fed in the center.&nbsp; If it&#039;s not a 1/2 wave length long, but still fed in the center, call it a doublet instead of a dipole.&nbsp; Just a difference in terminology, but it can sure clear up mistakes in what you are talking about.There&#039;s no significant difference between the radiation pattern of a vertical dipole and an end fed 1/2 wave vertical antenna.&nbsp; The biggest differences between the two would be in how the input impedance is handled.&nbsp; That end fed 1/2 wave will have a very high impedance and is why the &#039;A99&#039; uses a matching device at the input.&nbsp; That matching device is probably the biggest draw-back to them, it does have limited power handling ability.&nbsp; If the thing was center fed with no matching device used, that power handling ability would be much greater.&nbsp; That&#039;s not done all that often because mounting a center fed antenna isn&#039;t exactly as easy as an end fed one.&nbsp; Oh well...The only significant difference between a 1/4 wave, 1/2 wave, or 5/8 wave vertical is in the shape of it&#039;s radiation pattern.&nbsp; None of them &#039;radiates&#039; any more power than is fed to them, they just &#039;put&#039; that power in different places.&nbsp; The total amount is still the same.&nbsp;- &#039;Doc</blockquote>

[QUOTE="W5LZ, post: 408717, member: 129"] Just for your information... A dipole is commonly thought of as a 1/2 wave antenna fed in the center. If it's not a 1/2 wave length long, but still fed in the center, call it a doublet instead of a dipole. Just a difference in terminology, but it can sure clear up mistakes in what you are talking about. There's no significant difference between the radiation pattern of a vertical dipole and an end fed 1/2 wave vertical antenna. The biggest differences between the two would be in how the input impedance is handled. That end fed 1/2 wave will have a very high impedance and is why the 'A99' uses a matching device at the input. That matching device is probably the biggest draw-back to them, it does have limited power handling ability. If the thing was center fed with no matching device used, that power handling ability would be much greater. That's not done all that often because mounting a center fed antenna isn't exactly as easy as an end fed one. Oh well... The only significant difference between a 1/4 wave, 1/2 wave, or 5/8 wave vertical is in the shape of it's radiation pattern. None of them 'radiates' any more power than is fed to them, they just 'put' that power in different places. The total amount is still the same. - 'Doc [/QUOTE]

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