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Radar Timeline
1904: 30 April. The "telemobiloscope" (radar) patented and demonstrated by German engineer Christian Hülsmeyer. Telefunken refuses to buy his patents.
1916: February. German Richard Scherl produced the 10cm wavelength "Strahlenzieler" (Raypointer). German Navy rejects it as "not important tot he war effort."
1920s: British Dr. Robert Watson-Watt discovers the theory of radar just after WW I while trying to find a way to detect thunderstorms.
1933: Germany develops the "seetakt" carrier wave (CW) radar that operates at 50 centimeters on 50 watts. It can detect a 500 ton ship at over 7 miles. It is used exclusively as a range finder.
1934: Naval Aircraft Radio Lab produces a pulsed radar that detects aircraft at one mile.
1934: Dr. Robert Watson-Watt produces a radar operating at the 50 meters that can detect an aircraft at ranges of over 80 miles by bouncing the radar off the ionosphere.
1935: September. Germans mount first naval radar on "Welle", operating at 48cm.
1936: Germans produce the Freya surveillance radar operating at 125 Mhz.
1937: British begin installing "Home Chain" defense radar operating at 27.5 Mhz..
1937: Germans install Freya chain along their North Sea coast.
1937: Naval Research Laboratory installs a 200 mhz radar set on the 5"/38 guns of the USS Leary that can detect targets at 16 nautical miles. The antenna measures 10' x 10'.
1938: Germans field the "Seetaktisch Gerät" (Tactical Sea Instrument) operating at 375 khz (80cm), that can detect a target at 11 miles. It is used as a range finder on Admiral Graf Spee.
1938: British invent the ring oscillator, an important component of more powerful radars.
1938: British detect targets at 100 miles, the Americans 25 miles.
1938: USN equips the USS Leary with a radar operating at 1.5 meters detecting aircraft at 100 miles.
1939: Americans install the "XAF" radar operating at 1.5 meters on the USS New York. It has a "bedspring" antenna measuring 17 feet square and is sensitive enough to detect the splash (fall) of artillery shots. Renamed the "CXAM", the USN orders 20 more.
1939: By May British install a radar operating at 1.5 meters on aircraft and detect ships at 5 miles.
1939: November. British invent the cavity magnetron, allowing microwave radar development.
1940: SC radar operating at 50 centimeters is installed on most US ships.
1941: German Telefunken introduces "Wurtzburg," an improved radar operating at 570 Mhz.
1941: Fire Direction radar is added to the Mk 37 fire director on 5" guns.
1941: Microwave Surface Search Radar model SG radar is fielded.
1941: Late in the year PPI is fielded, greatly improving radar accuracy and usefulness.
1943: Most US Destroyers and Cruisers have SG radar and Fire control radar, allowing them to find "blind" at targets beyond the horizon in any weather conditions.
1943: August. Germans discard "Metrox" and issue the "Hagenuk" radar detectors to their U-Boats, later to replace it with an improved "Naxos" and more sensitive "Fleige". German submarines received their first radar, the "Hohentweil."
1943: Americans field the 10 Ghz surface vessel radar. Germans counter with the "Muecke" detector.
1944: Allied ships are fitted with the SR radar able to detect aircraft 150 miles away. Most ships already have the SC radar (air and surface warning radar).
1944: In October, U.S. Forces detect Japanese ships and destroy 1 battleship, damage 1 battleship, and sink 2 destroyers at a range of 36,000 yards. U.S. Battleships open fire at 22,800 yards, sink the damaged battleship and heavily damage a cruiser. The battle was fought and won entirely with radar! This was the first video war.