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Old 5-May-2011, 12:33 AM   #29
GroundUrMast
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Join Date: Oct 2010
Location: Greater Seattle Area
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Quote:
Originally Posted by Tower Guy View Post
Another plan would be to have the antennas about 2-4' apart vertically and also offset a total of 31 1/8" left/right. (Or one antenna would be 15.0625 to the left of center and the other would be 15.0625 right of center.)

That solution would add a bit of vertical beam width adjustment as well. A plus when trying to reject the signal from a tropospheric path. If the signal from the offending source is arriving at an angle from above, the simple 2D trigonometry starts to fail. Again, we can estimate the spacing but it may need to be adjusted in the field.

Now I'm wondering if a Rhombic would be an easier solution to fabricate... http://forum.tvfool.com/showthread.php?t=291 It can certainly be less visible than the erector set of hardware needed for an adjustable horizontal stack. At 40 to 70 feet long, front to back, it would be tough to fit on many city lots.

Or a huge 20+ foot home-brew Yagi. (See attached) (Which will not offer the deep null that is possible with the horizontal stack.)
Attached Files
File Type: txt CH-7 12 Director Yagi - Metal Boom - Non-insulated.txt (1.9 KB, 924 views)
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Last edited by GroundUrMast; 5-May-2011 at 1:04 AM.
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