High-frequency direction finding - Wikipedia
WEBFH4 "Huff-duff" equipment on the museum ship HMS Belfast. 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.
Introduction to HF - Part 3 of 3 : Aerials - Essex Ham
WEBAn aerial works best when it’s tuned to the frequency you are operating on – Whether it’s a vertical, horizontal dipole or a beam (yagi), if the size isn’t correct for the frequency, performance will be poor. A simple formula to find the wavelength of a frequency in metres is 300/freq (MHz), eg: 300/14.2 = 21.13m (hence the 20m band).
MF/HF Equipment tests: how to do it and actions in case test fails
WEBMay 15, 2016 · Many stations are equipped with only MF DSC Frequency, for sure we will not receive anything if we try it on some other HF frequency and another important thing is check the rough distance between ship's position and the coast station and choose the frequency accordingly.
Aerials and RADHAZ - commsmuseum.co.uk
WEBAWF. A permanent fixed transmitting whip aerial fitted in many surface units. It operates in the HF band with a maximum efficiency in the region of 7MHz and with medium powered transmitters - up to 1kW. The aerial rod consists of four tapered steel rods screwed together to form a length of 35 ft.
HF/DF - Royal Navy High Frequency Radio Direction Finding, …
WEBIntroduction. Land and shipboard high-frequency radio direction finding (HF D/F or Huff Duff), is now generally recognised as being with radar and code-breaking, a primary factor in the allied victory in the Battle of the Atlantic against the German and Italian submarine onslaught against shipping. Perhaps this is evenly balanced?
The HF Communications Renaissance | L3Harris® Fast. Forward.
WEBWith the inherent ability to communicate at distances that span the globe, HF has provided an accessible and versatile tool for long-haul communications. During World War II, for example, HF communications were the primary means for ship-to-shore and ground-to-air communications.
The High Frequency Direction Finder (HF/DF) - uboat.net
WEBThe High Frequency Direction Finder. Next to code breaking and radar HF/DF (known as "Huff Duff" to the sailors) was probably the most dangerous allied technology facing the U-boats. The technology was not new, as it had been used to find bearings on medium and low frequencies for navigation purposes for years.
High-frequency direction finding facts for kids - Kids encyclopedia
WEBHigh-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.
Measurement of the radiation patterns of navy shipboard High …
WEBOct 1, 2015 · A HF transmission is characterized by two components: a groundwave and a skywave. The groundwave follows the surface of the earth and provides useful communication up to about 650 nautical miles (nm) (1000 km) over salt water and from 10 nm (16 km) to 100 nm (160 km) over land.
New Tactical 3DHFDF Fixes High-Frequency Radios in 160 …
WEBJun 16, 2013 · Its advanced technology requires comparatively very small antennas for aerial purposes or small pick-up antennas for shipborne and ground platforms in order to provide an HF COMINT and geolocation capability which up to now, was provided only by antenna arrays measuring tens of meters.
Skip to content