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Historical documents report of the three systems on the island, two had been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
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,
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.
In 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
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)!
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while tying up your telephone line, and a nice lady's voice announced "You've Got
Mail" when a new message arrived...
All trademarks, copyrights, patents, and other rights of ownership to images
and text used on the RF Cafe website are hereby acknowledged.