Hi Mike!
I think both systems would give you outstanding results!
My current 160 antenna has lots of radials (120 per element (5) that are 1/4
wavelength (137 feet) long = 75,000 feet of wire (radial wires intersect with
buss wires and strap to conserve wire)). GROUND mounted radials under all
elements are very important for this antenna to work. As mentioned in the ON4UN
book, it has great F/B (32 dB at its peak) and has as much gain as a traditional
full size 4 square array. It is easy to match and assemble, however the useable
F/B is limited to about 50 KHz (a good 4 square would have more F/B bandwidth).
The parasitic system requires less real estate than a 4 square.
If you decide to go with a 4 square you would have to give consideration to
detuning the central tower, otherwise performance will be sacrificed.
VE3EJ, AA1K and others have installed the parasitic system I am using on 160 and
report super operation as well.
I just finished the installation of a 10 meter 4 square with 5/8 wavelength
elements (with 60 1/2 wave radials per element). This will be an interesting
antenna. We'll try it out during the ARRL DX Contests.
There are lots of pictures of my 160 and 80 meter vertical arrays on
http://www.k3lr.com
The 10 meter pictures will be put up soon.
Very 73 and Happy New Year!
Tim K3LR
K4PI wrote:
> I need some opinions on a direction to go with an array I have built. It is
> a 4 square for 160 M using 90 ft vertical T's with 45 ft top hats supported
> by a center 140 ft tower. At present it is being fed by phasing lines
> through a borrowed Comtek box. My original plan was to buy the DX
> Engineering phasing box once they get it to market but after studying the 5
> element array on page 13-31 of Low Band DXing, 4 the edition I am now
> questioning that decision. K3LR is the one that used the array on 160
> whereby he feeds the center tower only and uses the other verticals as
> directors or reflectors plus an omni selection by floating all the elements.
> Each vertical is changed from reflector to director by means of a relay and
> a loading coil. The big question is whether to proceed with the DX Eng
> driven system which give 8 directions plus omni or going with the parasitic?
> By the time it is all said and done probably price is not a factor as I have
> already laid the phasing lines out . The price on the parasitic would be
> the cost of the relays, boxes, inductors, omega match caps for center tower
> and all the control line cable plus the time of tuning them. The driven
> system would just be buying the phasing box and hooking it up as the
> vertical are all tuned. Any comments?
> 73 Mike K4PI
>
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