Note: Click on any picture to get a
Sec. 15.217 Operation in the band 160-190 kHz.
(a) The total input power to the final radio frequency stage (exclusive of filament or heater power) shall not exceed one watt.
(b) The total length of the transmission line, antenna, and ground lead (if used) shall not exceed 15 meters.
(c) All emissions below 160 kHz or above 190 kHz shall be attenuated at least 20 dB below the level of the unmodulated carrier. Determination of compliance with the 20 dB attenuation specification may be based on measurements at the intentional radiator's antenna output terminal unless the intentional radiator uses a permanently attached antenna, in which case compliance shall be demonstrated by measuring the radiated emissions.
What Is A LowFER beacon?
The word LowFER is a pseudo-acronym that stands for Low Frequency Experimental Radio and the basis of this facet of radio experimenting is based on FCC rules 15.217 (see sidebar) which allow unlicensed operation within these rules. Over the years, there have been many beacons operated and, more recently, a petition to create an amateur radio band in that frequency range (see the links to related pages - particularly the AMRAD link, below.)
As can be read into the FCC rules, the limitations currently put on LowFER operations are quite severe: It is extremely difficult to make a 15 meter antenna operating the 160-190 KHz range radiate efficiently - not to mention the 1 watt power restriction!
Nevertheless, these are part of the challenge. Despite these restrictions, impressive DX has been achieved on the LowFER band with these restrictions, including California-Hawaii and transcontinental DX (I personally was able to receive the 8LXJ beacon from Ohio when I lived in Flagstaff, Arizona on at least one occasion.) Traditionally, CW has been used as it is an effective narrowband mode and takes no sophisticated equipment to receive. More recently, modes such as QRSS (Extremely low-speed CW - go here to read more about QRSS operation) and BPSK (Bi-Phase Shift Keying) have begun to see increased usage.
Being non-licensed operation, most LowFERs (many of which just happen
to be amateur radio operators) use a few letters from their amateur
or their initials. While I know of no specific laws against using
an amateur callsign in non-licensed operation, I (and most other
have refrained from doing so. What about a portion of a
I see nothing wrong with that (a portion doth not a callsign make...)
it may make it possible to work out who really operates the beacon in
absence of other information.
Fairly recently, two different LowFER beacons operated from
A historical background (or "Beacons of the Past"):
My interest in MedFER (Mediumwave Frequency Experimental Radio) and LowFER operation goes back well over a decade. (Go here to see a growing archive of information on past "CT" LowFER beacons.) Starting in about 1986, I put my first LowFER beacon on the air from Flagstaff, AZ on 177.76 KHz. This beacon ran CW, signing the call "CT" (my initials.)
This beacon evolved over time: It was moved to 177.750 KHz. I later moved to Utah and operated from there for a couple of years. On this new frequency, I operated 10 baud CCW (Coherent CW) as well as 10 (and 1) baud BPSK using ASCII and the beacon was synthesized and kept to within 0.1 ppm of the desired frequency. This beacon was successfully copied on CW in California on numerous occasions, and fairly consistently in Wyoming on BPSK.
I later moved again but did very little LowFER operation as the layout of the yard, available trees, etc. precluded putting up a reasonable antenna and laying a decent ground. Instead, I put a MedFER beacon on the air on 1625 KHz. This beacon was copied over 700 miles away (this was before the "new" part of the AM broadcast band - from 1605 to 1705- was used for broadcasting.)
Times and interests change: In recent years, I have had several opportunities to put either a LowFER or MedFER beacon on the air, but I just never got around to doing either until recently.
The big question: Why?
Why do all of this? Former (?) LowFER Don Pomplun (K2BIO) put
it well: "A friend asks why I would be interested in listening to
weak stations that in fact don't even have anything to say. I've
found that LowFERing and ham radio can be likened to bird
That answer seems to be more acceptable, even if no more explainable!"
A Brief History of my LowFER activity (Transmitting):
(Let me first mention that I do not currently have a LowFER beacon of my on on the air. Now that I have said that...)
I put my first LowFER beacon on the air from Flagstaff, AZ on 177.76 KHz back in 1986. This beacon, like its successors, have signed the call "CT" (my initials.) I decided that "OEI" (or something like that) was too confusing a melange of dits and dahs to be copiable in very noisy conditions (it's my callsign, so I can decide what I want!)
As I recall, this beacon was heard (by "NVA" himself) in Pahrump,
well over 100 miles away. Not great DX, but at least I was
out. I rebuilt the transmitter and changed the frequency to
KHz and made provisions for this transmitter to be phase-locked to an
reference, but I don't recall ever running it in that mode while I
Then I moved to Bountiful, Utah and operated from there for a couple
of years on 177.750 KHz where I operated 10 baud CCW (Coherent CW) as
as 10 (and 1) baud BPSK using ASCII. The beacon was synthesized
the frequency and timing was kept to within 0.1 ppm of the desired
This beacon was successfully copied on CW in California on numerous
and fairly consistently in Wyoming on BPSK (See QSLs and pictures.)
Over the years, I have heard several LowFERs (other than my own signal.) As far as I know, none of these beacons are still on the air (at least at their original locations.) All of the recordings were made at approximately 0800 UTC on 19 December, 1987.
One of the strongest (non-local) beacons was NTS (see the QSL on the
sidebar) run by Dave Stinson, AB5S/7 from a location very near the
test site at Mercury, Nevada. Almost any night that the noise
overwhelming, this beacon could be heard on 189.8 KHz. Another
was beacon NVA from Pahrump, Nevada (listen to beacon NVA here.)
Having a lot of empty ground (and time and energy to put up the the
correctly!) resulted in this beacon being audible on its 177.26 KHz
A bit farther afield was the beacon "SUK" (listen to that one here) operated by Gary Waldsmith, K4SUK from Eldorado Hills, California on 174.39 KHz. There was beacon 7FS operated by Steve Ratzlaff (listen to it here as recorded through a 30 Hz wide audio filter centered on about 500 Hz) on 174.85 KHz from Belfair, Washington. If you listen to this recording, you'll see that the signal was very close to the noise, taking several passes of the ID to piece it together.
Much closer to home, there was the MPM beacon operated by Mark
WB7CAK (on 175.000 KHz, I believe) and the FAW beacon on 175.703
This latter beacon was operated by Chris Spencer, WB7FAW from Orem,
(and you can hear it here.)
Chris has put the FAW beacon on the air again, this time on 184.4 KHz
These days, many of the LowFER beacons operate, in addition to plain CW, more "digital-friendly" modes such as QRSS (very slow CW), WOLF and JASON - just to name a few - that allow much weaker signals to be decoded using DSP techniques.
The following are a few links that (may) have something to do with LowFER and MedFER operation:
The "CT" MedFER beacon - A PIC-Based PSK31 MedFER beacon
"QRSS and you..." - Using absurdly low-speed CW for "communications"
Using your computer to ambush unsuspecting NDBs - A brief description of how Spectran may be used when trying to receive NDBs.
A Line-Synchronous noise blanker for VLF/LF/MF use - This blanker produces very little intermod as compared to many others.
The Longwave Club of America: "The World of Radio Below 500 KHz" - Also covers MedFER operation
Any comments or questions? Send an email!
This page copyright 1999 - 2008 and maintained
Clint Turner, KA7OEI and yes, I know the background is for the MedFER
This page last updated on 20081229