Thread: Rca ant751
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Old 16-Apr-2017, 2:09 PM   #14
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,353
Diagram revised:



I suspect that the insulated UHF parasitic element in front of the UHF driven element Tetrapole is actually a pair of side-by-side directors that you also see in high gain UHF yagis by other manufacturers. The Tetrapole, AKA 3/4 wave folded dipole, has two current loops that allow the use of pairs of directors in front of it for maximum gain. But, I can't be certain until I have a 751 in front of me to confirm it.



You can see the idea of director pairs in Winegard patent 3,518,693. The patent drawing shows pairs of directors, but the patent text claims "a plurality of director elements."

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File Type: jpg RCA ANT751elementsRev.jpg (118.5 KB, 6827 views)
File Type: jpg WinegardPatentDirectorPairs.JPG (174.3 KB, 3576 views)
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Last edited by rabbit73; 16-Apr-2017 at 5:04 PM.
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