[TowerTalk] Vertical antennas

[w8ji.tom]

Hi Carlau,

> I'm looking for a good antenna system for 80 meters.
> I have visited:
> 1) the site of gladiator (http://www.primenet.com/~bmyers/) where they
speak of a four sqare arrays.
> 2) the site of Titanex (http://www.qth.com/titanex)
> where they have a vertical for 160 m with a tuning unit for 80 meters.
> How do they work ? 

First, let me say they both seem to be good verticals. The Unihat is
another one, although it seems to have problems handling high power.

But you asked how they "work", and that depends on a lot of things. Most
important is ground conditions near the antennas as well as the actual
ground system you use.

Most vertical antenna performance is limited by ground losses, and not by
antenna losses.

Any vertical with a good radial system will work OK. If you look back in
QST and other magazines, you'll see some very small verticals that were
very impressive. Jerry Sevik wrote some good articles, as did WJ Byron
W7DHD in Ham Radio.

To give you an example, I had a 32 foot tall vertical with a good trap at
top (air wound coil spaced well away from metal and a Teflon "sliding
capacitor" for tuning). It had three fifteen foot top hat wires connected
above the trap, that doubled as guy lines and a 1/4 wl stub running up the
side for 30 meters.
It was mounted over 60  50 foot long radials.

It consistently tied a 110 foot high dipole (a real dipole) on 80 meters
into Europe, and compared favorably to a 85 foot high dipole for 40 for DX.
I spent about $100 to build it, including the ground system. I'm absolutely
sure there isn't a single commercial antenna made that would have beat the
performance of this cheap home-made vertical. Once something is near 100%
efficient, it's tough to make it better.

On 80 meters, it beat a GAP Titan by about four S units, and about two S
units on 40. It was also 5 dB better than a full size vertical with four
elevated radials on 80, even though it was only 35 feet tall!
   
>Which is the best system ?

The best system is always the one that we think works best or that an
antenna company sells, no matter how well it really works. 

73 Tom

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