37 ms·
What HF means in this context? A few GHz? Also, for long range I thought the longer the wave length is, the better.
by DeathArrow 3y ago
What HF means in this context? A few GHz? Also, for long range I thought the longer the wave length is, the better.
- SigmundA 3y agohttps://en.wikipedia.org/wiki/High_frequency https://en.wikipedia.org/wiki/High_frequency
- macnetic 3y agoHF is 3 MHz to 30 MHz. Yes it does not make much sense, the term is ancient.
- nativeit 3y agoI mean, any higher and I’ll have to start thinking about printed circuit boards, shielded wires, and non-coat-hanger-based antennas…frankly if 30,000 kilocycles can’t get the job done, I’ll just have to light the thing on fire and use it to make smoke signals. Best regards, 50 years ago
- xattt 3y ago640 K[Hz] ought to be enough for anybody.
- 1992spacemovie 3y agoIf you did a modicum of reading it makes sense.
- yau8edq12i 3y agoAncient? The HF band is still very much in use... Modern developments have not changed the fundamental properties of RF propagation. UHF ("a few GHz") can only be propagated in line of sight reliably. HF can literally travel around the world.
- lxgr 3y agoGP called the term ancient, not the band itself, and I find it hard to disagree with that. Calling something “high”, “fast”, or “new” is rarely a naming decision that’ll stand the test of time, but given that there were already LF and MF below it, it did make sense at the time. Who could have predicted we’d go up all the way into visible light with our RF communications? The only thing on a lower frequency used daily by most people would be contactless payment cards and maybe NFC at around 13 MHz.
- yau8edq12i 3y agoMillimeter wavelength RF was already studied in the 19th century... The RF communication band you're talking about is smack dab in a band already defined in the original 1937 document. Honestly the naming scheme makes sense to me. The spectrum is divided into 12 bands of equal (log) size, up to a frequency where we don't know whether such waves will ever be reliably generated at room temperature without breaking the laws of physics. Then these bands are consistently named from "extremely low" to "extremely high", with an extra annoying band at the top. Really, it could be worse.
- zamadatix 3y agoI agree it could be worse but the idea it's really any good seems more like us being used to it than anything else. It's a stupid naming scheme. For a log scale I would really have been happier with everyone using band numbers or something rather than explaining "super high frequency" is higher than "Ultra high frequency" and, despite the terms, that's probably where most typical radio device use cases are these days.
- lxgr 3y agoFortunately we have not just one but two competing band designators – IEEE (widely in use in e.g. satellite communication; L-band, Ku-band, Ka-band etc. come from that nomenclature) and EU/NATO (which seems somewhat obsolete) :) In addition to that, hams (in study materials and exams) use wavelengths, which is always "fun" to convert from/to frequencies.
- lxgr 3y agoEven today, it still is higher than low and medium frequency :)
- PM_me_your_math 3y ago[dead]