In techno-speak, it's called the "SCR-270." Harold M. Watson wanted one badly.
In the old photograph, the antenna-like contraption towers over a huge flatbed trailer. It doesn't look like much. But to Watson, it might as well have been made of gold.
For three years, the retired Westinghouse engineer searched the globe for a 270. He telephoned people in Japan, the Aleutian Islands and Panama.
But no one could help him.
Until last summer.
An amateur historian read that a Canadian university was running physics experiments with a 270. The historian saw the antique radar, and like Watson, saw more than a jumble of rusted metal.
During World War II, the 270 radar offered a revolutionary way to detect enemy planes.
On a winter morning 49 years ago this Friday, two Army privates in Hawaii were testing a 270, training to read the radar scope.
"They saw targets coming in and called up the officer of the day," said Watson. "Here was a poor guy who'd only gotten to Hawaii two weeks before.
He didn't know what radar was or how to spell it."
The commander told the radar operators to ignore the big blip. He believed the screen showed an expected flight of B-17 bombers flying in from the mainland. So, while Americans slept and radar operators felt secure in their reading, 190 Japanese planes descended for a surprise attack. The bombing crippled the U.S. battle fleet, damaged the base and killed 2,403 Americans.
The 270 has been known as the Pearl Harbor Radar ever since.
"The day after Pearl Harbor everyone became aware that radar was something you had to have," Watson said. Wars never would be fought in the same way again.
Soon, visitors to the Westinghouse-supported Historical Electronics Museum will be able to see two of the few remaining Pearl Harbor Radars, thanks to retired engineers from the Linthicum plant who plan to restore them to working order.
Watson, a 40-year Westinghouse employee who retired as general manager of the Space Division in 1983, calls the radars the museum's most historically significant artifacts. And they're something no other museum has, Curator Bob Dwight believes.
The historians will display one of the radars just outside the museum.
Since August, Watson and about five volunteers have been restoring its trailer and painting pieces that, surprisingly, suffered no more wear and tear over the years than surface rust.
When it's finished, a 60-foot mast will support a 20-by-40 foot antenna.
Volunteers are reconstructing the second 270 radar at the Westinghouse Radar Range on Ridge Road.
They hope to finish both antiques by next December, in time to ship one of them to Hawaii for Pearl Harbor Day's 50th anniversary, Watson said.
In the museum, Westinghouse displays its own inventions -- such as satellites, radios and the lunar television camera that recorded astronaut Neil Armstrong's first steps on the moon -- as well as its competitors' inventions. It happens, though, that the company played an instrumental role in developing the Pearl Harbor Radar.
In the 1930s, Army, Navy and English researchers experimented separately with radar. When scientists from the three labs sat down together in 1938, they successfully designed the 270 to detect aircraft within a range of 150 miles.
In 1940, Westinghouse won the contract to produce the 270. During the next three years, the Radio Division in Baltimore built almost 800, subcontracting trailer production to a New Jersey company. The United States placed radar every 100 miles along the Pacific coastline.
But soon, the low-frequency 270s became outdated, as researchers developed more sophisticated, higher frequency radars. The United States sold some of its 270s to less technically advanced nations, which ultimately stopped using them, too. Most of them just rotted where they stood, Watson said.
Three years ago, Watson and other volunteers began phoning nations they believed might have used 270s, Army and Air Force bases, the Federal Aviation Administration, museums and universities.
And then one day, Dwight got a call from an amateur historian who had read in Wheels and Track magazine that the University of Saskatchewan, in Saskatoon, Canada, had been using 270s to measure a magnetic field known as the Northern Lights.
The university agreed to donate the historical radars to the museum, which had them shipped to Westinghouse in July.
Now, Watson thinks back to his countless phone calls. He remembers one with special satisfaction.
He'd called the Army Signal Corps electronics museum in Fort Gordon, Ga.
When the curator there heard what Watson was after, he said, "If I find a 270, you aren't going to get a smell of it."