On 1/25/2012 3:09 PM, Stuart Rohre wrote:
Les Moxon. in his RSGB England book, "HF Antennas for all Locations"
shows ladder line fed quarter wave verticals as you describe.
BALANCE is defined by equal impedances from each side of the circuit to
the reference plane (in this case, the earth). The feedline is only one
part of that circuit, and using twin lead does NOT provide balance if
the ANTENNA is not balanced and the antenna tuner is not balanced. A
vertical antenna is NOT balanced.
The primary virtue of using higher impedance feedlines has NOTHING to do
with balance, but rather that their higher impedance reduces losses if
the system is matched. But twinleads are just as likely to carry common
mode currents and couple them to the antenna if they are not very
effectively choked.
73, Jim K9YC
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