[TowerTalk] Top Loaded Towers

[Andy Reed]

As a visitor to Towertalk from the UK I'm trying to find some information
on alternatives to umbrella top loading for electrically short LF (<100kHz)
antennas.  
I'm sure I remember seeing a photo of a 1000ft or so tower with a spiral top
hat loading arranging.  It may have been for the Navy or USCG. Anyone know
where I can find any data or photos?
Thanks

Andy