Highland Ham wrote:
I have corrected the attribution marks below.
Wonder what newsreader you are using?
Highland Ham wrote:
So it makes no sense to connect an OCF Dipole directly to a twin
feeder .
Cecil Moore wrote:
So exactly to what feedline does it make sense to
connect an OCF Dipole?
========================================
To coax via a (voltage)balun (usually 4:1 )
The balun being either a ferrite bar or a toroid , wound with 1 bi-filar
winding eg a 2 to 1 (auto)transformer resulting in 4:1 impedance
transformation.
A 4:1 voltage-balun balances the voltages so
with unequal impedances looking in each direction
at the feedpoint, the currents will be unbalanced
causing feedline radiation. That's why the Carolina
"Windom" (sic) has a choke some distance down from
the feedpoint.
So an OCF Dipole seems to have feedline radiation
with either twinlead or coax+voltage-balun. The ARRL
Antenna Book says a 4:1 current-choke-balun will solve
the feedline radiation problem but 4:1 current baluns
usually require two cores.
--
73, Cecil
http://www.w5dxp.com