> Antenna is Butternut HF6V on the roof of our two story
> house, and the shack is on the lower level. Antenna
> ground is about 60' of 2x14 romex. Don't know what the
> solid wire equivalent of 3 #14 wires is offhand. But it
> terminates on the opposite side of the house from the
> station ground, clamped to an 8' ground rod driven in
> 7-1/2'. My station ground system has all major components
> connected to #2 stranded copper wire, about 30' total
> length, which terminates clamped to a 1/2"x8' electrical
> ground rod, driven in to within about 4" of the surface.
> Nothing else is connected to either the antenna or station
> ground. There is a ground wire for the house electrical
> panel that seems to be #2 stranded copper, but I can't
> tell where it's terminated underground since the ground
> here is a tad bit frozen right now. Everything in the
> shack connected to AC is on a separate circuit run
> directly to the panel, as is the 220V amp. Rig is a
> FT1000MP Mk 5 and the linear is an Emtron DX-3.
Bob,
You've invested a great deal of time and money installing a
less than ideal mix of toroids when the real problem is the
horrible ground system on your vertical. Your antenna has
virtually no ground at all except what comes through the
coax shield back to the station and to a lesser extent the
romex wire and ground rod.
We can all be sure the MAJOR part of your ground system for
the antenna is the house wiring and everything connected to
the house wiring. The minor part of the ground is that 60
feet of romex terminated in an 8 foot rod.
Every single ampere of current going up into that vertical
at the feedpoint must be matched by exactly the same current
flowing from the feedpoint of the vertical to a ground
system. That's just a fact of life.
That means the only two "ground" paths you have are the
romex and the outside of the shield of the coax. The long
romex will have a terrible common mode impedance at radio
frequencies, and the ground rod termination means about
nothing. A single rod, no matter how deep into the soil, has
dozens or hundreds of ohms RF resistance.
The first step is to rethink the antenna system. When using
a vertical Marconi antenna of any form we absolutely must
get multiple radials under the antenna right at the base of
the antenna. In the first place having those radials will be
the same difference in signal level as running an amplifier.
You will get stronger and at the same time probably hear
much better. In the second place WITHOUT the addition of
multiple radials the coax shield and anything near or
connected to the coax shield and that romex wire will all be
part of the antenna system. It will all radiate like crazy.
The time to worry about the beads and other RFI mitigation
is after the antenna installation is fixed. Not before.
73 Tom
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