The MFJ-931 effectively places your rig near actual earth ground potential even if your rig is on the second floor or higher with no earth ground possible! It electrically places faraway RF ground at your rig. Even if you have a good ground, a long connection wire can ruin its effectiveness by isolating a true RF ground from your rig.
The MFJ-931 creates an artificial RF ground! It resonates a random length of wire thrown along the floor and produces a tuned counterpoise.
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