Reg, G4FGQ wrote:
"No it doesn`t! (Thus an antenna for which H=0.45 lambda can by suitable
top loading be made to have a field distribution in the vertical plane
of H=0.6 lambda.)"

Reg is right. Between two antennas there will always be differences.
But, as Richard Clark might say, "Does it make a Db of difference?" One
dB can easily be lost in measurement error.

Top loading has been around since at least 1909 when it was patented by
Simon Eisenstein of Kiev. Russia. See Fig 9-24 on page 9-17 of ON4UN`s
"Loe-Band DXing". Eisenstein shows current distribution on his patent
application. He gets the base current up as it might be in a full height
antenna.

I would believe what Terman wrote because I`ve never been able to
disprove anything he wrote. Now I look for my error in logic when
something of Terman`s seems wrong.

ON4UN says on page 9-29 of his 1994 edition of the Low-Band DXing book:
"Over sea-water the 5/8 wave has lost 0.8 dB of its gain already, the
1/4-wave only 0.4 dB." (It`s less than one dB).

Even a disappearingly small radiator produces radiation less than 1/2 dB
weaker than a 1/2-wave dipole, or a 1/4-wave vertical. In lossless
antennas, the only difference in radiated signal between the full length
antenna and a too-short antenna comes from the slight difference in
their patterns.

Short antennas have efficiency problems because they have low radiation
resistances. This low radiation reaistance goes not compare as well with
a given loss resistance as does the higher radiation resistance of the
full size antenna. However, great care can be taken with the too-short
antenna to minimize its loss resistance and get good efficiency.

You have only to consult the "ARRL Antenna Book" and compare a short
continusously loaded vertical`s performance with that of a full-size
1/4-wave vertical. In my 19th edition it`s on page 5-25:
"Fig 46-Helically wound ground-plane vertical. Performance from this
type of antenna is comparable to that of many full-size 1/4 vertical
antennas."

In 1949, I worked in a transmitting plant where two stations, KPRC, 950
KHz, and KXYZ, 1320 KHz, shared the same transmittinng tower. Both
stations had identical RCA 5-C, 5 KW transmitters. Regional coverage was
almost identical despite many more degrees in the tower at 1320 KHz than
at 950 KHz.

One of the operators at the stations was a ham. He was J.L. Davis,
W5LIT. J.L. had a new 1949 Ford with a cane pole bolted to the rear
bumper. The pole was wound nearly end to end with enameled wire to serve
as antenna for his mobile ham rig. He had no top hat at the tip of his
antenna, so sometimes when he was talking a high voltsage corona
discharge would plume from the top of his antenna. Very impressive
though no help to his QSO..

Bill Orr writes on page 78 of "Vertical Antennas":
"A helix length of about .05 wavelength or more provides good results as
a substitute for a full size quarter wavelength vertical antenna."

It worked for W5LIT.

Best regards, Richard Harrison, KB5WZI