I've written extensively on this and given talks at ham events. Both the
writing and slides for the talks are on my website, so I won't repeat
them here. If you care about the answer, read them.
What I WILL say here is this -- these antennas DO work, often quite
well, for TRANSMITTING. There's nothing wrong about that concept, and
how they work has been clearly understood for much of last century.
Their downside is that they are a sitting duck for the RF noise that has
increasingly surrounded our stations that prevent us from HEARING all
but the loudest stations that we want to work. Except for power line
noise, none of these noise sources existed until about the last 15-20
years -- the sources are all sorts of electronic devices and el-cheapo
power supplies for our devices. The average home has several dozen of
them. Multiply that by the number of homes close to your antenna(s). Any
imbalance in an antenna causes the feedline to be part of the antenna.
On TX, it doesn't matter, but on RX, because that feedline runs much
closer to those noise sources than the antenna (the antenna is up high,
so farther away, it gets more signal and less noise).
73, Jim K9YC
On Mon,12/12/2016 9:29 AM, Wilson Lamb wrote:
Never miss a chance to offer an uninformed opinion or dumb question!
What exactly does “unbalanced” mean in the context of the OCF feedline?
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