Think of the dual boom as an open wire transmission
line having a characteristic impedance of something
like 300 ohms, and a spacing of several inches.
The feedline should drop down vertically from its
attachment point to the two booms and then turn
and run parallel to the two booms, but below them
by 6 to 12 inches, so there is minimal disruption
to the open wire line. IMHO, taping it to either
boom makes no engineering sense at all. It does
make marketing sense, in that the antenna might
sell better if they show a nice "clean" installation
vs the feedline hanging down.
Some TV antennas are designed this way, and you
never see the coax taped to the booms. It just
hangs down.
Rick N6RK
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|