[TowerTalk] 4 SQUARE ORIENTATION

[W8JI@aol.com]

In a message dated 98-07-01 11:42:18 EDT, you write:

<< 
 My own experience with my 80 meter 4 square would indicate that the
 major lobes in the forward direction on the 4 square are really pretty
 broad.  In reality, there does not seem to be much of a "null" in
 between major lobes in the forward direction.>>

Very true. No reason to use a laser sight on a shot gun..even one with full
choke.
 
>>
 Performance in between two of the favored directions (like due west on a
 4 square that favors NW/NE/SE/SW) does not seem to suffer.  I sure have
 no problems here in the midwest working VK or Africa on 80 mtrs.
 However, it's not unusual to have the morning paths looking west
 frequently favor the SW antenna, sometimes even as far north as JA, I
 suspect due to the grayline effect.>>

Also true. I use about 120 and 240 degree shifts, which narrows the forward
lobe by moving the nulls up and off the back. This provides better and more
usable F/R ratio as well as a dB or so forward gain improvement.

Even with improved focusing provided by increased phase delay, front lobe HPBW
is not narrow enough to make precise aiming a problem. 

An important point is the second insulated and detuned tower and dipole
antenna, located several hundred feet due west of the four square and omni
antennas, causes a null that makes the antennas "more even" to near-due-west
stations like the VK's. I can measure that on the ground, and it shows up on
sky-wave. The null does not noticably affect other directions, including ZL or
JA (whom I can work on 160 during summer on rare occasion) or Europe.

Eventually (when I get a feel for what really plays well) I'll have some big
optimized 160 arrays. Right now I'm just checking out the relative value of
horizontal polarity vs vertical.



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