Before invented radar

Before the invention of radar to detect aircraft equipment and water enemy ships could be using acoustic location (sound).
P.S .: Description UNDER photo.








Rotary horn (topofon) - used as 'advanced' own ears. Invented by Professor Meyer in 1880.



Denmark. 30th.



Marine acoustic locator Frenchman Jena Osher (Jean Auscher), 1960.

MOBILE Locator


English mechanics experiments Reva Bacon (Rev JM Bacon) 1898



English locator MK1 (1914-1918 biennium). Was used in World War I to detect enemy aircraft.



Four "Ukhova" locator. Date and manufacturer unknown.



Acoustic locator, standing on the US Army in 1921



Czech locator, 1920 (?). Two ears are located in the vertical plane, two horizontal



Half Czech radar that could be used by one person.



English locator, 30s.



Japanese locators 30s.



French locators 30s.



English locator 1938



German locator RRH, 1940



Roll locator US Army (early 40's was)

Terrestrial and NOT MOBILE SPEAKERS location station ...


England, 1928 The ten concrete antenna.



England, 1930 Semidesyatimetrovy locator-wall. Could "hear" airplanes at a distance of 100 km