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7x7 UHF Arrow antenna for portable AO40

I am about to send a $42 check to Al Lowe at Arrow Antenna to buy a replacement set of 7 UHF elements.  He said he could also throw in a short scrap of boom tubing to allow me to lengthen the boom 2 inches.  That will allow me to offset the second set of 7 UHF elements by ¼ wavelength (6.75 inches).  Once I receive the extra elements, it should be easy to drill another set of holes in the boom and rivet the 2-inch boom extension to the handle.

Now it's time to build the power splitter/matching cables.  I ordered an all-female BNC Tee and four 75-ohm BNC connectors from RadioShack.com.  I have some 75-ohm RG-59 cable.  Now I need to figure out the exact length of the coax needed to make the ¼ wavelength matching cables.  I know the velocity factor of the coax (82%), but I don't know the "length" and velocity factor of a BNC plug/jack.

Is the velocity factor 100% for BNC plug, BNC jack, and BNC Tee?
Should I measure the plug/jack length from the point where the coax dielectric ends?
Is there a reference site somewhere with tips for building UHF phasing cables with different types of connectors?

Wayne Estes W9AE
Mundelein, IL, USA
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