Talk:Ultra low frequency

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I'm interested to know why there are no man-made transmitters in this range. I know next to nothing about radio matters in general, but I assume there is limited bandwidth at this range which makes transmission a waste of time. But if that's true, why are there transmissions on SLF and ELF? — Trilobite (Talk) 03:01, 24 Nov 2004 (UTC)

Mainly because you'd need an extremely long and the resulting signal would have almost no energy. Another limitation is that it is a very slow way (in information per time) method of sending messages. The even lower frequency ELF (extremely low frequency) is used to communicate with submarines because it can penetrate sea water to an appreciable depth (which is difficult). I changed the article to say no communications transmitters. There are signals in that range but it is just noise released by slowly changing electrical signals. RJFJR 16:48, Apr 2, 2005 (UTC)

ULF is used to detonate explosives in mines. You don't need to lay wires which just get blown up anyways. Pogostix 02:08, 31 Jul 2005

There are transceivers in use in this range. I work on directional drilling gear in the oil & gas industry, and we have some downhole RTs that operate in the ULF range. This is because they only need to transmit a short distance (tool to tool, not tool to surface), and higher frequencies would be quickly absorbed by the surrounding rock formation. Our RTs are operating at around 2kHz. I also wanted to add that there are no references listed in the "Earth Mode Communications" section. As a radio enthusiast and all-around geek, I found that section really interesting, and I would love to see some sources cited. Beefington (talk) 12:54, 22 October 2012 (UTC)

I think that there is an error in the frequency described to take up this ULF band. Please change this article accordingly!

Hyphen

I have undone the move to a hyphenated name. This is against the normal convention. Although ultra low frequency is a rare term in radio engineering one can compare ultra high frequency which is never hyphenated in the literature. SpinningSpark 01:06, 20 December 2013 (UTC)

It looks better without the hyphen. Graeme Bartlett (talk) 11:06, 20 December 2013 (UTC)

Should this be a disambiguation page?

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