Read it agaln, Gary... it does not say the signal doubles, it is
doubling the signal radiated hemispherically opposite earth,as compared
to a signal with no conterpoise to prevent signal propagation equally
in all directions...in a perfect world...but not being perfect there is
loss to grond depending on placement and conductivity vs. reflectivity,
etc
..... and if you read the thread this whole life altering issue has
mutated from a suggestion that one would not be well suited by
grounding their backstay if using it as an antenna

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The most obvious effect is that the ground forces the antenna's
radiation pattern to appear in the half-space above the ground. This is
illustrated by comparing the radiation around a monopole fed against
ground to that of a dipole in free-space. The monopole has twice the
power in the hemisphere above the ground compared with the power in
either hemisphere of symmetry for the dipole in free-space.
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