vlf


Posted on Feb 5, 2014

Very Low Frequency (VLF) radio signals and earth currents, and probably even fewer could really care about it. However, there are those who have a serious interest in such things, and actively persue the monitoring and recording of the effects, whilst theorising on how they might be caused, so at least I can rest reasonably reassured that I`m not completely alone here! My knowledge and experience of natural VLF


vlf
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phenomena is rather limited, but I enjoy the opportunity to set up my home made detection equipment somewhere away from built up areas and to just sit and listen to the variety of sounds, waiting for that really unusual one to come along. A bit like fishing perhaps. I first became interested in these natural VLF signals when I accidentally stumbled across them whilst conducting experiments in earth current communication, after reading about it in an old magazine, probably Practical Wireless. The article mentioned how bases were set up during the First World War for communication between the trenches, and I found the technique used very interesting - to the point of attempting it myself. Without going into too much detail, a signal is fed into the ground via two earth stakes set some 25 metres or so apart, and the signal can be received some distance away by using another pair of electrodes and some amplification. As it happened, I didn`t manage to get much distance during my tests - perhaps a couple of hundred yards - partly due to a high level of mains hum and other noise masking the quiet signals, but it did give me the chance to hear for the first time the sound of atmospherics which I almost instantly decided to investigate at the expense of any further trials in earth current signalling. Are you aware that very low frequency radio waves, way below the reach of normal radio receivers and so low that they fall into our...




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