There is an LF beacon operating in the Columbia area. It can be received out to about 200 miles via groundwave – much further with skywave. This station is operating as a proof of concept Low Frequency alerting station, as part of a DHS SHARES trial program.   Our Amateur HF community knows that long-range emergency communications  can become unusable when HF skywave propagation is disrupted by a disturbed ionosphere.  But groundwave communications independent of the ionosphere remain available.  Such LF stations can provide essentially omni-directional blanket Alerting and low-bit-rate information coverage, nearly independent of mountains or foliage, etc.

The local station is transmitting on a center frequency of 194 khz. The best way to receive it is to tune your receiver’s USB Mode to 192.500 kHz, and use FLDIG or an equivalent program set at ‘1500 Hz CENTER,’ with a very narrow filter – the signal is only 36 Hz wide, so I use a 50 Hz filter for best reception. 

The signal presently being transmitted is THOR-Micro, available free from fldigi. The signal is sent with a 50 second on, 60 second off duty cycle and runs 24/7.

We are very interested in getting signal reports, and prefer to get them taken near noon, when any skywave component is minimized.  Reports of just the observance of the signal in a waterfall display, even of just an audable signal strong enough for CW (here: on/off as above), or of course, copy of the brief Alert text in the message window of THOR-Micro. 

Send reports to Dan Goldston [email protected]

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