LowFER is a form of two-way radio communications practiced on frequencies below 300 kHz.


LowFER operation is practiced in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 and Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 on radio frequencies between 160 kHz
The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....

 and 190 kHz, which is sometimes referred to as the 1750-meter band. In the U.S., license-free operation is also allowed on the medium frequency band, also known as the AM Broadcast Band. Proposals have also been made for Amateur radio
Amateur radio
Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...

 operations at 136 kHz with a number of U.S. Hams
Amateur radio operator
An amateur radio operator is an individual who typically uses equipment at an amateur radio station to engage in two-way personal communications with other similar individuals on radio frequencies assigned to the amateur radio service. Amateur radio operators have been granted an amateur radio...

 holding experimental licenses authorized to conduct tests on that frequency. In Europe, the band is used for broadcasting and is unavailable for two-way communications use. In the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 there was an allocation for radio amateurs at 73 kHz from 1998 to 2002. The International Telecommunication Union
International Telecommunication Union
The International Telecommunication Union is the specialized agency of the United Nations which is responsible for information and communication technologies...

's 2007 World Radiocommunication Conference
World Radiocommunication Conference
World Radiocommunication Conference is organized by ITU to review, and, as necessary, revise the Radio Regulations, the international treaty governing the use of the radio-frequency spectrum and the geostationary-satellite and non-geostationary-satellite orbits. It is held every three to four years...

 (WRC-07) in Geneva
Geneva In the national languages of Switzerland the city is known as Genf , Ginevra and Genevra is the second-most-populous city in Switzerland and is the most populous city of Romandie, the French-speaking part of Switzerland...

 agreed a secondary allocation 135.7-137.8 kHz to the Amateur Service on Friday, November 9, marking the first time since amateur allocations began that there has been an amateur band below the Medium Wave broadcast band.

U.S. and Canadian radio operators who conduct low-frequency experimental operations on the LowFER band are known as LowFERs. Many LowFERs are also licensed radio amateurs
Amateur radio operator
An amateur radio operator is an individual who typically uses equipment at an amateur radio station to engage in two-way personal communications with other similar individuals on radio frequencies assigned to the amateur radio service. Amateur radio operators have been granted an amateur radio...

, although an amateur radio license is not required for LowFER communications in those countries.


Antenna efficiencies at these frequencies make it difficult to radiate much useful power. By current U.S. and Canadian regulations, LowFER transmitters may not use antennas longer than fifty feet or final RF
Radio frequency
Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...

 stage input powers that exceeds one watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...

. In the United Kingdom (which only has LowFER allocations for licensed amateurs), the limit is one watt erp
Effective radiated power
In radio telecommunications, effective radiated power or equivalent radiated power is a standardized theoretical measurement of radio frequency energy using the SI unit watts, and is determined by subtracting system losses and adding system gains...

, meaning an inefficient antenna can be fed a higher power. Telegraphy
Telegraphy is the long-distance transmission of messages via some form of signalling technology. Telegraphy requires messages to be converted to a code which is known to both sender and receiver...

 and digital modes are the most commonly used for communications, but speech transmission via amplitude modulation
Amplitude modulation
Amplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...

 (AM) or single-sideband modulation
Single-sideband modulation
Single-sideband modulation or Single-sideband suppressed-carrier is a refinement of amplitude modulation that more efficiently uses electrical power and bandwidth....

 (SSB) is also allowed. Even with such short antennas and low transmit power, lowFER stations have been heard at distances approaching 1000 miles by listeners using sophisticated receiving setups.


Similar to LowFER, MedFER is medium-frequency experimental radio. MedFER enthusiasts operate using 0.1 W (a tenth of a watt) and a three-meter-long antenna between 510 kHz and 1705 kHz, coinciding with the U.S. AM radio band.


HiFER is high frequency experimental radio operating within a 14 kHz-wide band centered at 13.56MHz. (See RFID for other uses of this frequency).

External links

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