An acoustic listening device developed for the Dutch army as part of air defense systems research, 1930s
An acoustic listening device developed for the Dutch army as part of air defense systems research, 1930s. Van Soest designed a device with two half parabolas which were sealed by flat plates separated at a mutual distance of 16 centimetres with 8-centimetre holes at ... Acoustic location was used from mid-WW1 to the early years of WW2 for the passive detection of aircraft by picking up the noise of the engines. Passive acoustic location involves the detection of sound or vibration created by the object being detected, which is then analyzed to determine the location of the object in question. d the advantage that they could ‘see’ around corners and over hills, due to sound refraction. The technology was rendered obsolete before and during WW2 by the introduction of radar, which was far more effective. The first use of this type of equipment was claimed by Commander Alfred Rawlinson of the Royal Naval Volunteer Reserve, who in the autumn of 1916 was commanding a mobile anti-aircraft bat...