THE 5/8 WAVE VERTICAL

This type used by many, It has deserved a name on the DX-antenna list
over the last years.
Often bought by those who have a 1/2
wave vertical but want to put more effort in the antenna system.
The radiation pattern is also a omni-directional one. It has somewhat
higher gain then his smaller brother (the halfwave vertical), actually it is 1,5dB stronger.!!!
And yes, this difference is "just" noticeable, but no way this will result in an one extra or several extra S-units.
The SWR can often be changed at the bottom of the antenna by changing the coil dimensions, you can easily change the SWR.
Other forms of "tunning" are those with changing the total antenna
length by changing the top element, often you will not have to change
anything since the manufacturer has put markings on the aluminum.
Some manufacturers would like to let you know that with something on
top of the antenna (as you can see in the picture above) the
antenna will work better this of course is also not true....but it
looks nice.
And there are those who claim high gain. As said the 5/8 wave antenna has 1,5dBD NO more, no mather what type!
LONGER THEN A 5/8 WAVE
For us DXers it has no advantedge of building or buying a vertical
antenna with a longer length then about 7 meters. The take-off angle
will not be any lower and the longer antenna brings along more lobs in the antenna pattern wich are divided many times so they
tend to be weaker.


Above we see the pattern produced by a 5/8 wave antenna with a length
just under 7 meters. When you compare this to a halve wave vertical you
can notice there is only a slight difference, NOT that much though.
Looking at A the angle is again around the 16 degrees, the antenna is only situated 0,5 meters above the ground!
At B you can see that the
take-off angle is very wide even the noticeable dip in the pattern is
only 1 dB down to its strongest point! so this will suite you just fine
for all DX.
With C (15 meters) and D (25 meters)we come in the lower take-off angles the serious DX is found there. But
the antenna is already up quite a bit and a small horizontal placed
beam at these heights will outperform the vertical almost anytime.
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