Dave wrote:

I was taught that there is a 90 degree phase shift in an inductor.

Dave, there is a phase shift between applied voltage and maximum
current. That should not be confused with phase shift or phase
difference in current at both ends of the inductor.
,
in a loading coil there must be less than 90 degree phase shift because
the top portion of the antenna still has a small, ~3 to 5 degree, phase
shift required to achieve resonance. So, does the inductance have a 90
degree phase shift or an approximate 85+ degree phase shift.

No.

What happens in an antenna is voltage and current are out-of-phase by
some amount. This by definition means the antenna is reactive.

The loading coil's primary function is to shift voltage in relationship
to current, and compensate the relationship between voltage and current
so they are back in phase.

If the loading coil is physically large and has a good amount of
displacement current flowing radially to space and objects around the
antenna compared to through current, the coil would have a noticable
difference in current at the bottom terminal and top terminal. The
current also would also not be in phase when compared at each end.

Voltage and current are in phase at the base and 90 degrees out of phase
at the tip, at resonance, conclusion: less than 90 degree phase shift in
the inductor. PLEASE EXPLAIN this physics anomaly!

Again, you are comparing electrical degrees of the antenna with degrees
phase shift between voltage and current in a circuit containing only a
pure inductor.

Degrees of antenna only deals with the length. It is a way of
expressing length in terms of wavelength, with 360 degrees being a full
wavelength.

Degrees of phase angle in an antenna or any load is really just a
comparison between voltage and current. It is not related to electrical
degrees.

Mixing those two very different things up is a source of great
confusion. If we have a 10 degree tall antenna we really don't need an
inductor that behaves like it is a 80 degree long antenna section to
resonate the system, and the system is not "90-degree resonant". It is
simply resonant. The antenna is 10 degrees long, and the coil is
whatever it needs to be to bring voltage back in phase with current.


Consider this. If I have a coil in series with a resistor and measure
the input voltage as a reference point, the current at BOTH ends of the
coil will lag voltage by a certain amount. If the coil has low
capacitive reactance to the outside world compared to the load
resistance, current at each end of the coil will be essentially equal.
Phase shift in current at each end will be very low.

It's only when the coil becomes physically large and has appreciable
capacitive reactance to the outside world compared to the load
impedance that it starts to show significant transmission line effects.

Every bit of this is not difficult to understand if we really
understand how an antenna behaves and how a coil behaves. The only
source of wonderment and argument seems to come from people who want to
make the inductor behave differently in an antenna than it behaves in
other systems.

It really isn't complicated at all. The very first post in this 900
plus post long thread explained it quite well, and it's been explained
dozens of more times along the way. There is no reason to assign
special properties to an inductor and make it behave differently in an
antenna than it does in other systems.

73 Tom