Published in The Coast Star on May 29, 2003

Page 15

 By Fred Carl

SCR-584 at Camp Evans with IFF unit

    When one examines a June 1945 aerial photo of Camp Evans, radar domes are seen on the roof of ‘the Marconi Hotel.  In the hotel attic are workbenches and special
screened cages for sensitive electronic work left from World War II.  What was done here?
Our suspicion was the work involved the application of microwave radar and the development of the anti-aircraft radar system, the SCR-584.
A declassified August 1943 Camp Evans secret project report gave detailed SCR-584 information long before the radar was first used in February 1944 at the Anzio, Italy invasion by Allied forces.
Mr. Wilfred Lawson, of Belmar, confirmed our suspicions.  During World War II, he worked in the Marconi Hotel attic.
He was in the middle of top secret electronic development.  He worked on special receivers in one of those cages.
Now after 60 years it is safe to disclose his work, which was key to World War II Allied antiaircraft defense.
The problem the engineers of Camp Evans needed to solve was aircraft identification.  The Massachusetts Institute of Technology [MIT] had designed a fantastic radar prototype, the XT-1 in record time using the British cavity magnetron.
The new cavity magnetron-based radar could direct antiaircraft guns to hit planes two miles away.  It would shoot at any plane, friend of foe.
How could you tell if the plane or bomber was a friend or a foe from that far away?  You could not even see the plane, never mind read its markings.
An automatic radar identification system was needed.  It had to be created with the utmost secrecy.  If Nazi spies learned of the details of the system they could develop ways to confuse the system.  This could cause the Allies to shoot their own planes.
It takes time to develop and test complex electronic systems.  The Camp Evans team had to create experimental units and improve the system step by step.
An early step was to develop radar-to-plane communication that was easy for a busy bomber or fighter pilot to use.
A test unit Mr. Lawson worked on was a transmitter and receiver pair.  The transmitter was atop the Marconi Hotel roof in one of the radar domes.
Mr. Lawson’s test unit would transmit a coded radio signal to a plane flying around Camp Evans.  If the equipment worked correctly, when Mr. Lawson turned on one, two or three lights on the transmitter, the pilot would see the same number of lights on his unit in the plane. The pilot would push a but-ton indicating the number of lights he saw. The pilot’s unit transmit-ted the number back to the hotel attic. This identified the plane as a friend or foe and all the pilot had to do was push a button.
During 1942 and 1943, the equipment was further developed and integrated into the new radar, now called the SCR-584.  The system had to indicate where planes were on a radar scope and work with hundreds of planes at the same time.
The system had to work on many radio frequencies to make it difficult for the Nazis to jam.
Finally, in late 1943, the entire system was ready to be tested to make sure it would not fail in battle.  When the finished radar detected a plane, it would transmit a code to interrogate the identity of the plane.  A friend would have a receiver unit that would respond with the correct code, while a foe would not.  The radar would direct the guns to shoot at foes and not at friends.  IFF – interrogate friend or foe – was born.
The Camp Evans draftsman created drawings for American industry to build the units by the thousands. User and service manuals were written in the building that Brookdale Community College is now using for the start of the Communiversity. Radar operators and repairmen were trained at Fort Monmouth. Receivers
were installed in Allied planes and bombers at Allied airfields – all in secret.
Point Pleasant Borough resident Joe Leber was a radar operator on the Anzio beachhead in 1944 when the SCR-584 was first used.  His radar and artillery unit was protecting the hotly disputed beach from Nazi dive bombers with the original Army radar, the SCR-268.
The SCR-584 was deployed just in time.  The Nazi radar engineers had developed radar jamming equipment for use against the SCR-268.  The Luftwaffe planes effectively used their new jammers the first few days during the Anzio invasion until the SCR-584s were put into action.
The Nazi bombers, confident with their new radar jammers, were soon flaming wrecks – the jammers did not work against the SCR-584.  Mr. Leber witnessed firsthand the deadly effect the SCR-584 had on the Nazi Luftwaffe.
American and British radar experts once more outwitted the Nazis in the radar war and Camp Evans played a key role

[Fred Carl is the director of the Infoage Science-History Center at Camp Evans.]

page created August 30, 2003