On the topic of Wullenweber antennas, SWLing Post reader, Mike, points to this article on U-T San Diego’s website:
Navy’s mysterious ‘elephant cage’ retired: Cold War-era structure a visual landmark on Silver Strand
Beachgoers will say goodbye this month to the “elephant cage” — the mysterious metal structure that has graced the south end of the Silver Strand for 50 years.
The Navy will demolish the circular cage-like contraption as part of an initiative to get rid of obsolete gear.
Officially known as the Wullenweber Antenna Array, the 1,300-foot-diameter structure was built in 1964.
Many details are shrouded in Cold War-era secrecy, Navy officials say.
[…]In simple terms, the huge circular antenna was used to intercept radio signals and detect which direction they came from.
With a range up to 3,200 nautical miles, the Silver Strand antenna likely monitored the Pacific Ocean and parts of Central and South America.
U.S. allies around the world also housed “elephant cages” during the Cold War.
One was located in the United Kingdom, to intercept signals originating from Warsaw Pact nations in Eastern Europe as well as portions of the former Soviet Union.
Another array, located in San Vito dei Norrnanni Air Station. ltaly, opened in 1960 to monitor areas of the Middle East.
Others were built in West Germany, the Philippines, Japan and Canada.
In order to preserve history, the Navy plans to keep the five tallest screens plus some guy wires and anchorage posts. It is also working on a digital 3-D model of the antenna.