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Low Frequency Radio Transmission

AncientMariner
The annual Christmas Eve message will be transmitted in Morse code on December 24th at 08:00 utc (UK Time) on 17.2 kHz. Tuning up commences at about 07:30 utc.

If interested and you do not have a suitable receiver in the conventional sense, you can use the sound card in your pc and this software https://sites.google.com/site/sm6lkm/saqrx/ together with a decent length of wire.

The transmission will be screened live at  YouTube Channel.

Clive

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  • 0
    Not I suspect while deeply submerged - the "skin depth" at 200KHz will be around a metre, in typical sea water, and as you lose nearly 9dB per skin depth,  a mere 10m of seawater cover is a 90dB loss - a lot even for an ultra narrowband system to recover a signal from. Mind you, if you only want to know if the carrier is still there or not, then you do not need much bandwidth. Systems are a little more sophisticated than just assume a nuclear war has started if you cannot listen to The Archers,  but even so anything with any bandwidth of mention, needs something, even if it is only the antenna part, to go up to the surface.

    The VLF navigation systems were VLF for a good reason like the US Omega system used 14kHz for example.
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  • 0
    Not I suspect while deeply submerged - the "skin depth" at 200KHz will be around a metre, in typical sea water, and as you lose nearly 9dB per skin depth,  a mere 10m of seawater cover is a 90dB loss - a lot even for an ultra narrowband system to recover a signal from. Mind you, if you only want to know if the carrier is still there or not, then you do not need much bandwidth. Systems are a little more sophisticated than just assume a nuclear war has started if you cannot listen to The Archers,  but even so anything with any bandwidth of mention, needs something, even if it is only the antenna part, to go up to the surface.

    The VLF navigation systems were VLF for a good reason like the US Omega system used 14kHz for example.
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