Hi Rollerball Rocco... Antennas, The Mi-Amigo had so many! .... It was first used off Sweden as Radio Nord
well before Atlanta/ Caroline got the ship.... Off Sweden, they knew what they were doing....
going for a Frequency at the Low end of MW around 600kc...Using this end of the band, brings with it
antenna problems, Especially at Sea, where you ideally need a much taller mast, to get it to work well

Radio Nord brought in a real Antenna guru, John H Mullaney, he had worked on Military really Low freq
antennas, so MW was relatively easy for him, He actually went to the Mi-Amigo, to help with the antenna
Antenna talk is full of Lingo, (especially Amateur radio ones) each with their own weird name,
that confuses things.... But in reality, the more it changes, the more it's a Variation of the same thing

It's Easy to understand VHF-FM antennas, as the Whole thing is quite small, mounted as high as possible
But with MW AM Antennas, The Huge size needed, for the long wavelengths, makes full size Antennas difficult
So the use of the Ground (soil) for the Lower half of the antenna, started well before Marconi
(who did Not Discover/ Invent radio, but that's another story)... this means Antenna can be Half the height

But if you use soil, for the Lower Half, soil is not a very good Low resistance thing, Some soil types very poor
so On land, wires are buried to try to reduce the soil losses, But at Sea, no Soil involved, one reason that
offshore radio was so good, at putting out decent signals...

The Radio Nord Antenna was sort of Shunt fed, with No Base Insulator used, When Atlanta obtained the Mi-Amigo
they didn't use the original system, so they removed the Radio Nord special " 603kc huge Tuning Boxes"
and went for a conventional type system at the 1.6 Mhz end of the band, where a shorter antenna is practical

Antenna systems at Sea, have the problem of the Huge forces of wind, and the movement of the Ship in bad weather
so fixing a mast directly to a ship, needs special heavy duty guy rigging, so the ship and tower move together
That's why Base Insulators were often Not used at sea, In fact, one Mi-Amigo tower, had Insulators, and they
welded brackets across them to make tower stronger...RNI and the 284 foot Ross Revenge tower were Grounded
without base Insulators as well, both using a shunt fed Tap for the feedpoint

The best compromise for Low freq antennas, is the so called "Inverted L"... if you have two masts, using an "L"
gives a longer Horizontal top, than a true Marconi "T", enabling resonance with less base loading coil
but it's not totally omnidirectional, that is to say, signal will be stronger in some compass directions
The Laser antenna, was a variation of the Inverted L, Paul Rusling termed it a "7" antenna, worked well

Rod Watts