LowFER
(
Low
-
F
requency
E
xperimental
R
adio) refers to experimental radio communication practiced by hobbyists on
frequencies
below 300 kHz, a part of the
radio spectrum
known as
low frequency
. The practitioners are known as "
LowFERs
".
Practices
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]
LowFER operation is practiced in the
United States
and
Canada
on
radio frequencies
between 160
kHz
and 190 kHz
[1]
which is sometimes referred to as the
1750-meter band
,
[2]
and in the past as the
1875-meter band
.
[3]
In much of the world, including the U.S., there is an adjacent
amateur radio
band
at 136?138 kHz
with a number of U.S.
amateur radio operators
authorized to transmit on that band (notification and lack of objection from power utilities is required).
Radio operators who conduct low-frequency experimental operations on the LowFER band are known as
LowFERs
(pronounced "loafers"). Many LowFERs are also licensed
radio amateurs
, although an amateur radio license is not required for LowFER communications in those countries in Region 2, as long as the power is below a nationally prescribed limit, often 1
W
.
[4]
[5]
Equipment
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]
Practical antennas at these frequencies are much shorter than the wavelength, making it difficult to efficiently radiate much useful power. By current U.S. and Canadian regulations, LowFER transmitters may not have antenna and feed line lengths longer than 15 metres (49 ft), or final
RF
stage input powers that exceeds 1
watt
.
[6]
Telegraphy
and digital modes are the most commonly used for communications, but speech transmission via
amplitude modulation
(AM) or
single-sideband modulation
(SSB) is also allowed. Even with such short antennas and low transmit power, LowFER stations have been heard at distances approaching 1,000 miles by listeners using sophisticated receiving setups.
[4]
Similar activities
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LF amateur radio allocation
[
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]
In Europe, and generally in ITU Region 1, the LowFER frequency range (160–190 kHz) is used for broadcasting and is unavailable for two-way communications use. In the
United Kingdom
there was an allocation for radio amateurs at 73 kHz between 1998 and 2002. The
International Telecommunication Union
's 2007
World Radiocommunication Conference
(WRC-07) in
Geneva
agreed a secondary allocation 135.7–137.8 kHz (the 2200-meter band) to the Amateur Service on 9 November 2007, marking the first time since amateur allocations began that there has been an amateur band below the
medium wave
broadcast band. Transmitter power is limited to one watt
ERP
(meaning an inefficient antenna can be fed a higher power).
MedFER
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In the U.S., license-free operation is also allowed on the medium frequency band, also known as the AM broadcast band. Similar to LowFER, MedFER is medium-frequency experimental radio. MedFER enthusiasts operate under FCC Part 15 rules 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.
[4]
HiFER
[
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]
HiFER is high-frequency experimental radio operating within a 14 kHz-wide band centered at 13.56 MHz.
[7]
This frequency range is allocated to
industrial, scientific and medical
uses as well as low-power communication devices under
FCC Part 15
rules, where a small level of radio frequency radiation is allowed without licensing. (See
RFID
for other uses of this frequency.)
See also
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References
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External links
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