The antenna array is composed of three concentric rings of antenna elements. Each ring of elements receives RF signals for an assigned portion of the 1.5 to 30-MHz radio spectrum. The outer ring normally covers the 2 to 6-MHz range (band A), but also provides reduced coverage down to 1.5 MHz. The center ring covers the 6 to 18-MHz range (band B) and the inner ring covers the 18 to 30-MHz range (band C). Band A contains 48 sleeve monopole elements spaced 78.4 feet apart (7.5 degrees). Band B contains 96 sleeve monopole elements spaced 37.5 feet (11.43 m) apart (3.75 degrees). Band C contains 48 antenna elements mounted on wooden structures placed in a circle around the central building. Bands A and B elements are vertically polarized. Band C elements consist of two horizontally polarized dipole antenna subelements electrically tied together, and positioned one above the other."
The array is centered on a ground screen 1,443 feet in diameter. The arrangement permits accurate direction finding of signals from up to 4000 nautical miles away.
FLR-9s were constructed at the following places:
Clark AB, PI
Udon, Thani Province, Thailand
Misawa AB, Japan
San Vito, Italy
The dismantling of the FLR-9 at Misawa is on-going and due to be completed this year (2015). The last AN/FLR-9 in existence is at Elmendorf AFB Alaska.
Enough distractions, I need to complete a couple of End Fed HF antenna designs for portable use.