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Early Radar Development Video
Videos for Engineers

SCR-270 Radar at Pearl Harbor (Wikipedia photo) - RF Cafe Videos for Engineers

Videos for Engineers - RF CafeThis archive links to the many video and audio files that have been featured on RF Cafe.

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We read a lot about the early radar system that was in operation at Pearl Harbor in December 1941 when the surprise attack by Japanese naval airplanes decimated the fleet with a 3-hour-long raid beginning at around 8:00 on that sleepy Sunday morning. According to "The Untold Pearl Harbor Radar Story," by C.P. West, the SCR-270B (Signal Corps radio #270, rev B) radar system had a range of 250 miles at an altitude of 50,000 feet. Westinghouse built the system in 1940 following a development contract issued by the Army Signal Corps in 1936.

Historical documents report of the three systems on the island, two had been shut down and that with the remaining system, operators Joseph Lockard and George Elliot detected a formation of aircraft about 137 miles out to sea. They were told it was a squadron of B-17s and to not worry about it. The rest, as they say, is history.

Radar's roots go back to the late 19th century when Heinrich Hertz conducted experiments of radio signals being reflected off metal surfaces. In 1904, German scientist Christian Hülsmeyer gave a demonstration of his "telemobiloskop." By the early 1930s, the U.S., Great Britain, Germany, the USSR, Japan, the Netherlands, France, and Italy, were all working on radar development programs.

RF Cafe - Radar Oscilloscope Image of Pearl Harbor Japanese Attack FormationIn 1935, the British government commissioned Sir Robert Watson Watt to develop a "death ray" of microwaves to shoot down enemy aircraft. Although no death ray ever materialized, the work did lead to the world's first practical surveillance radar system. That led to the Chain Home coastal radar defense system that alerted Britain to Luftwaffe attacks in WWII.

Back in the day, the success of radar was dependent entirely upon the ability of the operator to properly adjust the system parameters and to interpret what was displayed on the scope. Modern radars use incredibly complex software algorithms to sort through data to determine not merely range and azimuth, but also altitude, velocity (direction and speed), acceleration, climb/descent rate, radar cross section (RCS), tracking history, type of target, threat assessment, and much more. Human operators are primarily used to make command decisions based on the computer's opinion.

The videos below are but a tiny sample of what is available on the Internet. Do a search on early radar development, airborne radar, shipboard radar, space radar, over-the-horizon radar, etc., for more information. Have the search engine in the video result mode to filter out text results.


The Development of Radar


Attack on Pearl Harbor


The Secret of Radar Revealed

I had not seen this footage for many years. You might see your father or grandfather there. It makes me think of September 11, 2001. The main difference is that the Pearl Harbor attack was initiated by one clearly identified country's military against another. 9/11 was a group of religious zealots, Muslim Extremists, against both civilian and military targets.

How many ways has your life been complicated by the 9/11 attackers and their ilk? Fondling and long delays at airports; government surveillance everywhere - cameras, FBI files for everyone and everything, GPS location reporting in your car and phone; taxation to pay for fighting the Muslim Extremists; being told by the Government that you must understand those who attacked you and tolerate hate-filled religious people and institutions right in your own back yard?

...and yet you keep voting for the same politicians who perpetuate this crap (both Ds and Rs)!

Here is a page on how aircraft were detected prior to the advent of radar.



Posted June 3, 2020

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