[Lowfer] Lowfer Beacons

[Lyle Koehler]

Mark, welcome to the club! With the exception of Dex's distinctive
sawtooth-modulated beacon on 510.5 kHz, I don't know if any MedFER beacon
has been heard for more than a couple of miles since the 1610-1710 kHz range
became populated with AM broadcast stations a few years ago. As for LowFER
beacons, there are many people who can't hear them, either. Often it is
because of
location -- either there are no LowFERs within 1000 miles and/or the local
noise level is simply too high to hear anything. Living near Memphis, at
least you have a fighting chance because there are quite a few LowFERs in
the southeastern US. XM, NC and RAL are good ones to look for, because they
have all been copied at great distances this season. In normal CW mode, you
might have a chance at copying BA and/or BOB by ear. Some listeners seem to
have success using spectrogram programs for detecting CW signals at speeds
faster than 5 WPM, but at those speeds an experienced operator can usually
hear them before they are visible on the screen.

Without knowing more details of your 7 foot loop and how it is connected
into the rest of the circuit, it isn't possible to analyze why it does not
appear to tune properly. As a wild guess (with a little help from the
RJELOOP3 program), it should tune to the LowFER band with about 400 pF of
capacitance. Of course, if there is any amount of coax in parallel with the
loop and the tuning capacitor, that capacitance (about 30 pF per foot of
50-ohm coax) has to be taken into account.

When using Argo for reception of QRSS60, the displayed bandwidth is only
about 3 Hz. Precise frequency accuracy is essential. As Denis Barton
suggests, setting the receiver to 59.000 kHz in USB mode and using WWVB as a
standard is a good place to start. But after doing that, I would make a few
further checks. Go to LSB mode with the receiver set to 61.000 kHz and see
if Argo reads the same thing. It should be very close. Then set your
receiver to 9999.000 kHz in USB mode and see if you still get a 1 kHz Argo
readout when listening to WWV. If, for example, you see that the audio
output is now at 980 Hz, it means that your rig's master oscillator is 2
parts per million high. You can either adjust the master oscillator, if it
is easily accessible, or calculate the error that you would have on the
LowFER band and take it into account when tuning either the rig or the Argo
center frequency. 2 parts per million would not pose much of a problem
because that's only 0.36 Hz off at 180 kHz. But some radios might be off by
considerably more than that. Finally, I'd go back to 60.000 kHz in CW mode
and use Argo to find out if the BFO pitch settings are accurate (if indeed
the rig has a calibrated BFO pitch control). Normally I would use CW mode
with the narrowest filter setting to receive QRSS signals. However, if the
BFO pitch is not accurately known, it is necessary to use either USB or LSB
mode, and to offset the rig's digital display by the desired center
frequency for the Argo display. For example, to receive NC at 177.777 kHz,
you could set the radio to 177.000 in USB mode and then center the Argo
display at 777 Hz. I expect that you already know all this stuff, but a
surprising number of hams find it difficult to grasp. If you want even
better precision, John Andrews has made some excellent suggestions for
calibrating receivers and sound cards using Loran signals, and a copy of his
article can be found on the LWCA web site.

As you are discovering, reception of LowFER signals can be very difficult.
That is why many people find it challenging (and why many others give up so
quickly)!

Lyle, K0LR