Talk:Radio frequency

message: Isn't there a ELF, Extreme Low Frequency ?
Yes, but there doesn't seem to be agreement on the extent of it, so I finally settled for "below 3 kHz." -Palmpilot900
: Try Extremely low frequency (SEWilco 08:34, 27 May 2005 (UTC)
thread_title:  ELF 

message: Maybe https://ewhdbks.mugu.navy.mil/freqspec.htm would be of use. (SEWilco 08:34, 27 May 2005 (UTC)
thread_title:  More charts 

message: Entering RF in search goes to RF disambig page, not here, so the RF connectors should be moved there.  They really don't belong on this page.  --Blainster 16:27, 14 July 2005 (UTC)
thread_title: RF Connectors

message: Hello.  Can anyone with an interest in this article suggest an article somewhere that might discuss radio spectrum pollution?  (More specifically, the problem of radio frequencies overlapping and so on -- I don't know if there are other names for it.)  I'm not exactly an expert on the electromagnetic spectrum, but a while ago I thought that the Light pollution article should be disambiguated from non-visual light, because as related as they are on some levels, that article doesn't presently discuss anything other than visible spectrum light pollution.  (It's also quite long, and the topics might work better being split anyway.)  At the time, I made a stub article called Radio spectrum pollution, but it's been a stub for a while, and I'm wondering if there might be a better place to disambiguate to.  Thanks for any help or suggestions. Izogi 04:05, 3 April 2006 (UTC)
thread_title:  Is there a radio spectrum pollution article anywhere? 

message: what does the "M" in front of the hertz mean?
:Mega, as in Megahertz. -- Beland 15:52, 22 June 2007 (UTC)
thread_title: MHz?

message: The wave lenghts are wrong. They are much too big. Check out the formula here in wikipedia under wavelength.
:They agree with the chart on Electromagnetic spectrum. -- Beland 16:03, 22 June 2007 (UTC)
thread_title:  Wavelength 

message: I came to this article for a definition of "radio frequency".  Alas, there doesn't seem to be one.  Instead, the article is about radio bands, and electromagnetic waves.
In normal usage, does a 500 kHz signal qualify as RF?  What about 50 kHz?  —EncMstr 22:34, 22 June 2007 (UTC)
thread_title:  article name 

message: can someone list where in this chart FRS and GMRS is? i think it can be useful for beginners.
thanks  —Preceding unsigned comment added by 76.254.10.81 (talk) 05:09, 22 December 2008 (UTC)
thread_title:   FRS  and GMRS

message: By convention the audible range is 20Hz to 20kHz which only partially covers ELF. Please correct the table text.  —Preceding unsigned comment added by 77.70.56.64 (talk) 18:26, 26 April 2009 (UTC)
replies: text: You're free to make such changes yourself:  This is an open wiki.  I've made a change; if you have ideas for improvements, be bold.  —EncMstr (talk) 19:10, 26 April 2009 (UTC)
replies: text: A mention on the page about the range that human hearing falls in would be an improvement.  No mention is made about sound or audio at the moment. Jonpatterns (talk) 18:14, 17 April 2014 (UTC)
thread_title:  ELF aren't audible 

message: I think Radio spectrum should be merged into this article.  RS is a terrible article with no references, but there are nearly 100 links to it, so it needs to be fixed somehow.  Thoughts anyone? Jonverve (talk) 21:13, 15 May 2009 (UTC)
replies: text:  In fact, it might be better to merge Radio spectrum with Radio waves?  —Preceding unsigned comment added by 81.152.168.210 (talk) 02:50, 4 November 2009 (UTC)

text: "just because a signal is oscillating at RF doesn't mean there are any waves emitted" Exactly how does that occur?? Has some recent discovery proven Maxwell's equations to be wrong?? This has profound implications! Zen-in (talk) 07:01, 7 November 2009 (UTC)
replies: text: Probably he means just because it's RF doesn't mean that there are significant or relevant waves emitted.  That is, the frequencies may mostly affect what's on wires, not wireless or radio, unless there are antennas involved.  There are waves on wires, too, of course, but if the wires are very short compared to a wavelength, that's not so relevant to the situation; and it's not radio.  Dicklyon (talk) 08:35, 7 November 2009 (UTC)
replies: text: Yep, that's what I meant. Think of designing an RF amplifier, rather than the antenna. Okay, there will be some small emission, but it's usually undesired and I don't think most designers would consider it. As another example, think of an RF probe for MRI - it's a near-field device, designed not to radiate.GyroMagician (talk) 11:40, 7 November 2009 (UTC)

text: You cannot have a travelling wave on a wire without emissions.  This is an immutable property of radiation. If there is a near field there is far field.  The only exceptions to this are Clown Physics, which has been known to exist in Wikipedia. Zen-in (talk) 16:04, 7 November 2009 (UTC)
replies: text: What's your point?  Are thinking someone is taking the clown side in your strawman argument?  Dicklyon (talk) 18:52, 7 November 2009 (UTC)
replies: text: Referring to "Antenna Engineering", a handbook I unfortunately can't afford, so I have to look it up in university library, antennas of physical size much smaller than 1/10th of a wavelength are very poor radiators, for well established physics reasons. Of course there is radiation emitted at any frequency, but if the antenna is small enough, the amount is minuscule compared to the energy flowing through the circuit, and reflected back into the circuit from the inefficient small antenna. Morycm (talk) 04:26, 3 February 2023 (UTC)
thread_title:  Merger proposal 

message: the resonant frequency formula needs fixed, the formula should be 1 over 2pi times the square root of L times C, i tried to fix it but idk how to get 1 to go over the entire formula.--159.218.81.233 (talk)
:Done. I swapped a \over b to \frac{a}{b} while I was there - it always seems more intuitive to me, but maybe I spend too long coding ;-) GyroMagician (talk) 16:24, 26 April 2010 (UTC)
thread_title:  Resonant Frequency Formula 

message: We appear to have a one-letter edit war. Or a 'k' flashing at a very low frequency! Rather silly. On the one hand, radio waves can most definitely be produced at 3Hz. On the other hand, I don't think any electronic/electrical engineer would define 3Hz as radio-frequency. What should be done? GyroMagician (talk) 07:34, 31 May 2010 (UTC)
replies: text: Thanks for adding this; it was something I meant to do after the last revert.  I've been removing the k in 3 kHz to be consistent with the article contents.  The only idea I have to prevent an endless loop of deleting and re-adding the k is to add a wikicomment explaining that it is not a mistake.  Any other ideas?  —EncMstr (talk) 08:30, 31 May 2010 (UTC)
thread_title:  Silly Situation (Hz vs. kHz) 

message: I've just rolled back (most of) several edits.  Those edits were largely to do with radio waves not radio frequency, and they are not the same thing. We already have an article on radio waves, and perhaps some of the material can or should be added to that article, if it is not already there. Mitch Ames (talk) 04:28, 10 April 2011 (UTC)
thread_title:  Radio frequency  vs radio waves 

message: The Very low frequency article has a table of transmitted signals. 17.5 kHz seems to be transmitting 20 second pulses, but the source is not listed. Is ET trying send a message to Jodie Foster. That article doesn't seem active so I thought I would post here. Is there any info about it to update the table or should I just put Lakeview Cemetery in Ithaca, New York as the source?--Canoe1967 (talk) 19:21, 15 June 2012 (UTC)
thread_title:  ET phone home 

message: Hi there,
I was looking that the rf spectrum table and noticed the format of both the frequency column and wave length column do not match 
example 3 – 30 MHz does NOT correspond to 10 – 100 m
the author or an editor needs to decide which column should determine the order of magnitude and then match the range in the other column accordingly 
example 3 - 30 Mhz, 100 - 10 m (NOT 10 - 100 m)
I'm surprised this boo-boo is both in the article and here in the talk.
I'm going to guess that this is just an oversight because we wouldn't want readers to get confused that small number frequency = small number wave length which is I know that everyone here on this talk page knows is incorrect :-)  — Preceding unsigned comment added by 24.6.92.28 (talk) 21:54, 17 June 2013 (UTC)
replies: text: I agree. Should we leave the Hz ascending and the wavelengths  descending?--Canoe1967 (talk) 00:51, 18 June 2013 (UTC)
thread_title:  I'm surpised both the table in the article and here in the talk have errors 

message: Frequency                   	Wavelength             	Designation                	Abbreviation
3 – 30 Hz              	105 – 104 km           	Extremely low frequency    	ELF
30 – 300 Hz            	104 – 103 km           	Super low frequency        	SLF
300 – 3000 Hz          	103 – 100 km      	Ultra low frequency        	ULF
3 – 30 kHz             	100 – 10 km       	Very low frequency         	VLF
30 – 300 kHz           	10 – 1 km         	Low frequency              	LF
300 kHz – 3 MHz   	1 km – 100 m      	Medium frequency           	MF
3 – 30 MHz             	100 – 10 m             	High frequency             	HF
30 – 300 MHz           	10 – 1 m               	Very high frequency        	VHF
300 MHz – 3 GHz   	1 m – 10 cm       	Ultra high frequency       	UHF
3 – 30 GHz             	10 – 1 cm         	Super high frequency       	SHF
30 – 300 GHz           	1 cm – 1 mm  	Extremely high frequency   	EHF
300 GHz - 3000 GHz	1 mm - 0.1 mm	Tremendously high frequency	THF
--Wyn.junior (talk) 04:16, 2 March 2014 (UTC)
replies: text: The ranges over which these frequencies can be used for communication depend on too many things, like do you mean between points on the surface of the earth?  or in space?  Do you mean to include other effects than curvature of the earth and ionospheric bounce?  Etc.  So there's really no answer that would make sense in the table; unless you find a source that attempts to do something that would be worth mentioning.  Dicklyon (talk) 05:57, 2 March 2014 (UTC)
replies: text: I guess I am talking about maybe setting up a point of communication distance for reference. Or maybe both in space and in an urban setting. I haven't found any sources for this info, though it seems very important to note.--Wyn.junior (talk) 10:44, 2 March 2014 (UTC)
replies: text: It is important, but probably too complex an issue to sum up in a neat table. Range depends significantly on things other than wavelength, such as transmitter power, type, size, and height of antenna and mode of transmission.  Ground waves, tropospheric scatter and skywaves can all achieve greater ranges than line-of-sight propagation.  Skywaves are particularly interesting in this question because there is a range greater than line-of-sight but less than the maximum skywave distance that skywaves cannot reach.  Thus, giving a maximum number would misleadingly include numbers that cannot be reached.  Skywaves can also achieve greater than the maximum range in some circumstances with multiple hops by bouncing off reflective surfaces such as oceans and lakes.  Further, the effectiveness of sky waves depends on time of day due to daily changes in the ionosphere.  If you are asking what is the maximum range a radio transmission could be made under any circumstances whatsoever then the answer is unhelpfully the size of the observable universe since a transmitter placed in space outside the Earth's atmosphere can transmit to anywhere not obscured by another object.  But I don't think that an entry of 14 gigaparsecs against every frequency band would actually be a useful addition to the table for anyone. SpinningSpark 20:50, 2 March 2014 (UTC)
thread_title:  Don't we need a section on this chart that says "range" for the distance the signals are effective at? 

message: in the paragraph "Thus, under similar conditions of propagation, the higher frequency signal attenuates faster than the lower frequency signal and becomes too weak to be detected at the end of the receiver, located at larger distances. An RF power amplifier is used to amplify the power level of such a transmitter RF Signal, so that it can travel larger distances with less attenuation."
1) the attenuation is independent of power, so higher power creates a higher signal, not less attenuation
2) also, the relation between wavelength and attenuation should be made more explicit (attenuation is per distance, not cycle, so to first order it should also be independent of frequency)
Chris2crawford (talk) 16:34, 14 March 2014 (UTC)
replies: text: Pretty much garbage, and it's uncited. I've removed it. SpinningSpark 22:57, 14 March 2014 (UTC)
thread_title:  misunderstanding of attenuation, power, and wavelength 

message: On the 12th of June I posted some comments that have been removed by EncMstr. Again, here are my comments on this article.
1. "High-power exposure to microwave RF is known to create a range of effects from lower to higher power levels, ranging from unpleasant burning sensation on the skin and microwave auditory effect, to extreme pain at the mid-range, to physical burning and blistering of skin and internals at high power levels (see microwave burn)."
This sentence does not make much sense to me. It's either incomplete or it needs to be rewritten.
2. "Additional rational for EMF restrictions is to avoid auditory effect and energy-induced unconsciousness in rats."
I don't understand this sentence. I think it needs to be rewritten.
3. The 3 links under "General RF exposure" should be moved to the "See also" section.
ICE77 (talk) 04:44, 8 July 2015 (UTC)
thread_title:  Comments on the article 

message: I am creating this section to discuss the proposal of Fgnievinski who on 2 February 2019 added a tag to the Radio-frequency current section, proposing to split this section off into a new article named Radio-frequency current.  He apparently didn't add any supporting discussion. ----ChetvornoTALK 20:24, 21 February 2019 (UTC)
replies: text: I respect Fgnievinski's motives, but oppose this proposal.  This article is nowhere near splitting size and has plenty of room for the discussion of radio frequency currents.   Radio-frequency current exists and is a redirect for this article.  We already have articles on Radio, Radio frequency, Radio wave, Radio spectrum, and Alternating current.  Splitting topics into a maze of small articles entails a lot of redundant explanation and does not serve readers. --ChetvornoTALK 20:24, 21 February 2019 (UTC)
replies: text: Thanks for your initiative. May I suggest instead renaming the entire article to Radio-frequency current. The reason is there is very little information other than in the section Radio-frequency#Current. (Disclaimer: I've just split off Radio-frequency#In medicine.) I also propose redirecting Radio frequency to Radio#Frequency. fgnievinski (talk) 22:35, 21 February 2019 (UTC)
replies: text: On the subject of redirecting the article to Radio, actually I am rewriting Radio per Talk page consensus as a WP:SUMMARYSTYLE article that is mostly devoted to applications and links.  The draft is at User:Chetvorno/work11#For Radio, would appreciate any criticisms or comments you have about it.   This huge article will not have much room, and I'm not sure the peripheral topic of "radio-frequency currents" is appropriate.   The term "radio" by itself mostly applies to applications that use radio waves for signaling across a distance, not radio frequency currents in wires; for example microwave ovens, diathermy equipment, MRI machines, internet cables, and cable television systems are not called "radio" even though they use radio frequencies. --ChetvornoTALK 06:19, 22 February 2019 (UTC)
replies: text: There is, however, an engineering discipline of "radio frequency engineering." It encompasses all the above equipment, and any other equipment that uses the range of frequency where particular RF engineering techniques and knowledge apply. I think there is a lot of confusion about what this article is supposed to be about. I suggest to stick to "RF engineering" as a scope definition. Morycm (talk) 04:49, 3 February 2023 (UTC)
thread_title:  Split off section into a new article, [[Radio-frequency current]]? 

message: , I don't fully agree with this edit which removed a paragraph which indicated the terms "long wave", "medium wave", and "short wave" are not well defined. Today there might be some standards, but I don't have any of them. Even if the standards do define the terms, I don't believe they were well-defined during the period they were avant-garde and receiving lots of attention. Jc3s5h (talk) 19:35, 28 February 2020 (UTC)
replies: text: I don't think a long paragraph where we display our anxiety about our lack of authority is what the reader comes here for. The band edges might not have been crisply defined for all time, but no-one gets muddled too badly - 120 kHz is long wave, 1200 khertz is medium wave, and 12000 kHz is short-wave and has been so for a long time. Unless there's some documented case of notable confusion, I don't think we should have the paragraph here. --Wtshymanski (talk) 20:44, 28 February 2020 (UTC)
replies: text: The paragraph that was removed was not well written. But I think a better (and briefer) description of how vague notions became fairly widely accepted definitions would be an improvement, rather than just giving definite values in the table with no hint that they're not all that standardized. Jc3s5h (talk) 21:21, 28 February 2020 (UTC)
replies: text: Even a well-cited discussion of the origins of these expressions would be probably irrelevant to this article. It's about "radio frequency" not "etymology of some radio jargon". --Wtshymanski (talk) 18:31, 29 February 2020 (UTC)
thread_title: Long wave, medium wave...

message: The usage of  (which currently redirects here) is under discussion, see talk:RF (disambiguation) -- 64.229.88.43 (talk) 05:46, 23 July 2022 (UTC)
thread_title: "RF"