Search results
Results From The WOW.Com Content Network
High-frequency direction finding, usually known by its abbreviation HF/DF or nickname huff-duff, is a type of radio direction finder (RDF) introduced in World War II. High frequency (HF) refers to a radio band that can effectively communicate over long distances; for example, between U-boats and their land-based headquarters.
Doppler DF is one of the most widely used direction-finding techniques. Other direction-finding techniques are generally used only for fleeting signals or for longer or shorter wavelengths. The Doppler DF system uses the Doppler effect to determine whether a moving receiver antenna is approaching or receding from the source. Early systems used ...
The Royal Navy also deployed direction finding equipment on ships tasked to anti-submarine warfare in order to try to locate German submarines, e.g. Captain class frigates were fitted with a medium frequency direction finding antenna (MF/DF) (the antenna was fitted in front of the bridge) and high frequency direction finding (HF/DF, "Huffduff ...
When that turned out to be the case, the Royal Air Force (RAF) introduced a different system that consisted of a set of tracking stations using HF/DF radio direction finders. The standard aircraft radios were modified to send out a 1 kHz tone for 14 seconds every minute, allowing the tracking stations ample time to measure the aircraft's bearing.
Maxwell K. Goldstein (January 15, 1908 – February 18, 1980) was a first generation Jewish-American scientist and engineer who was instrumental in the development and deployment of high-frequency direction finding by the United States Navy during the Second World War.
The array consisted of a ring of 120 vertical monopoles covering 2–20 MHz. Tall wood poles supported a 1,000-foot diameter (300 m) circular screen of vertical wires located within the ring of monopoles. His research is still used today to guide the design and site selection of HF/DF arrays. Records of his research are available in the ...
Radio direction finding equipment for eighty meters, an HF band, is relatively easy to design and inexpensive to build. Bearings taken on eighty meters can be very accurate. Competitors on an eighty-meter course must use bearings to determine the locations of the transmitters and choose the fastest route through the terrain to visit them.
The FRD-10 was designed to locate HF transmissions especially from submarines and was managed by the Naval Security Group. [2] The Navy also claimed over the years that the direction finding sites were used primarily for air and sea rescue operations [ 17 ] [ 19 ] and Naval communications in the case of the pair of FRD-10s at Sugar Grove Station .