Ad
related to: hjs hf df 1000 amp
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.
For this reason, Doppler DF systems normally mount their antennas on a small disk that is spun at a high speed using an electric motor. Performing the same calculation using an antenna mounted to a disk with a diameter of 50 centimetres (20 in) diameter spinning at 1000 Hz results in: S = .25 × 1000 × 101.8 / 48 = 530 Hz
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 ...
Initially three U Adcock HF DF stations were set up in 1939 by the General Post Office. With the declaration of war, MI5 and RSS developed this into a larger network. One of the problems with providing coverage of an area the size of the UK was installing sufficient DF stations to cover the entire area to receive skywave signals reflected back ...
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 .
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.
Adcock radio range ground station. Hundreds of these stations were deployed around the U.S. alone. The Adcock antenna is an antenna array consisting of four equidistant vertical elements which can be used to transmit or receive directional radio waves.
The AN/FLR-9 is a type of very large circularly disposed antenna array, built at eight locations during the Cold War for HF/DF direction finding of high priority targets. The worldwide network, known collectively as "Iron Horse", could locate HF communications almost anywhere on Earth.