That's pretty close. It's a 110 foot tower, with a 4 element 40 (linear
loaded) on top, and a KT-36XA at 75 feet. These two antennas have their
feedlines isolated from the tower, and the feed methods at the antennas
are isolated from the booms, so there is no low Z common mode path, and
neither
On 12/07/2012 08:29 AM, Tom W8JI wrote:
In this case the original poster has a two-dipole 80-meter antenna
attached high on a tower. He needs to isolate common mode 160 meter
tower antenna currents and voltages from that array.
1.) He clearly stated electrical length (and by definition that als
Right. 5K Ohms is a good rule of thumb for choking Z to prevent noise
coupling from feedline to antenna, and if the antenna is reasonably close
to balance, is also enough from the point of view of dissipation.
This is where we can all get into trouble. We need to carefully read,
consider, and
I'm with Tom on this one. This is not a noise suppression problem
The placement up high on the tower means that the common mode path is
nearer a voltage node than a current node and we are talking about the kind
of voltage up top there that can destroy a 4000 ohm ferrite device. As the
the resi
On 12/6/2012 12:39 PM, Steve London wrote:
My 160 meter shunt fed tower project is essentially done. However, I
have an issue with the 80 meter antennas hung off that tower. In a
nutshell, the current baluns (ferrite beads) feeding these antennas
don't have enough common mode impedance on 160 m
Google G3TXQ COMMON-MODE
Dave WX7 G
On Dec 6, 2012 1:40 PM, "Steve London" wrote:
> My 160 meter shunt fed tower project is essentially done. However, I have
> an issue with the 80 meter antennas hung off that tower. In a nutshell, the
> current baluns (ferrite beads) feeding these antennas don'
My 160 meter shunt fed tower project is essentially done. However, I have
an issue with the 80 meter antennas hung off that tower. In a nutshell,
the current baluns (ferrite beads) feeding these antennas don't have
enough common mode impedance on 160 meters. They heat up, and the SWR of
the shu
My 160 meter shunt fed tower project is essentially done. However, I
have an issue with the 80 meter antennas hung off that tower. In a
nutshell, the current baluns (ferrite beads) feeding these antennas
don't have enough common mode impedance on 160 meters. They heat up, and
the SWR of the shu
