Richard Harrison wrote:
ON4UN has a graph, Fig 9-22 on page 9-15 of "Low-Band DX-ing" which
shows current distribution of a base-loaded whip, In his example, the
whip is 45-degrees long.. The loading coil provides the extra 45-degrees
required for resonance.

Current at the base of ON4UN`s whip is one amp times the cosine of
45-degrees, or 0.707 amp. The loading coil has an input of one amp.

With 1 amp into the loading coil and 0.707 amp out of the loading coil,
the coil definitely does not have the same current at both ends.

It's not that perfect in the real world but the basic concept
still applies. The actual current at the top of the coil is
somewhat higher than 0.707 amp because the current inside
the coil is greater than 1 amp. EZNEC says the current about
1/3 of the way up from the bottom of the coil is about 1.15
amp. The inductance of the coil forces the phase between
the voltage and current to increase. To maintain the same
V*I*cos(theta) power, the current must also increase.

The high flux fields developed inside the coil somewhat distort
the perfect current cosine wave found in a thin wire dipole so
it is not quite as black and white as ON4UN indicates.
--
73, Cecil http://www.qsl.net/w5dxp