Talk:FM broadcast band
This article is rated C-class on Wikipedia's content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||
|
Request for improvement
I have added a few bits and pieces to the section on the Japanese FM band. Perhaps a Japanese wikipedian or someone who has lived in Japan can improve it further. Rugxulo 20:41, 19 January 2006 (UTC)
Bizarre process for merging
The link to 107.9 MHz shows a history [1] that the merging was performed one day after proposal, by the same person. Yet the merging was very evidently not a thorough job.
Why not let stubs lie until the main article is actually ready to take over for the stubs?
FM in Japan
Why can frequencies in the frequency range 90-108 MHz not used for FM radio in Japan? --84.61.74.254 18:31, 19 April 2006 (UTC)
- Allocated to other uses. --Kiand 21:59, 5 June 2006 (UTC)
To which uses is the frequency range 90-108 MHz allocated in Japan? --84.61.39.43 12:35, 11 July 2006 (UTC)
It is used mainly for Television
The future of FM?
Is there solid info anywhere on the future of analog FM radio in the USA? --Howdybob 05:18, 30 November 2006 (UTC)
- BTW, I'm unwatching this page so if anyone chooses to discuss this, I'd much appreciate if they left a message on my talk page. --Howdybob 03:01, 15 April 2007 (UTC)
Not going anywhere... IBiquity's IBOC system, the only one approved for use in the US by the FCC, actually requires an FM analog signal to be present; it becomes a set of added sidebands.
iBiquity - FM Waveforms VXO (talk) 02:40, 29 April 2010 (UTC)
ITU region 1?
The article now covers ITU region 2, Japan and OIRT pretty well but doesn't have a section on ITU region 1. I don't have the knowledge to add much although I live in that region. 86.16.37.189 (talk) 09:15, 18 May 2013 (UTC)
Center frequencies
It is easily verifiable - with a digitally tuned radio which tunes with 200 kHz channel spacings and a consumer fm transmitter which broadcasts with 100 kHz channel spacings - that signals broadcast on the off 100 kHz spacings are received with audio distortions and more noise. I have experienced this myself in everyday life. It does however seem reasonable to expect that in regions where 50 kHz spacings are used that the signals which would have the most noticeable distortions and noise would be those on the alternate 100 kHz spacings rather than those on the 50 kHz spacings; the alternate 100 kHz spacings would always be further from the 200 kHz spacings than the 50 kHz spacings. — Preceding unsigned comment added by Thisma (talk • contribs) 12:52, 3 September 2014 (UTC)
- A lot depends on the selectivity of the radio. If a radio does not have very selective tuning, then it is more tolerant of being somewhat off-frequency as it "captures" a wider frequency range at once. On the other hand, it will be more susceptible to interference from nearby stations and be less able to select only the wanted station. CodeCat (talk) 15:02, 3 September 2014 (UTC)
Can't find the West on any map - where is it?
- western countries
- Western practice
- western bandplan
- standardization with the West. — Preceding unsigned comment added by 220.233.48.191 (talk) 23:09, 20 December 2015 (UTC)
There is no reference to Asia
"China and other Asian countries go across the 76-108 FM spectrum" ,no only Japan. Source: https://www.radiodiscussions.com/showthread.php?557150-FM-Broadcast-Band-in-China-76-108-MHz — Preceding unsigned comment added by 2A01:C50E:8896:1000:9031:A83F:A67B:A66D (talk) 05:57, 3 September 2018 (UTC)
FM broadcasting in the United States
i notice there is a whole other article, FM broadcasting in the United States . Shouldn't that be at least referenced here, if not merged? — Preceding unsigned comment added by Gjxj (talk • contribs) 12:29, 29 September 2020 (UTC)
Neither article pays any attention to the history of fm stereo brodcasting. Presumably there is yet another article on that??Gjxj (talk) 12:32, 29 September 2020 (UTC)
- I believe it is well described, but I forget where. Some is in subcarrier but there is more. Gah4 (talk) 18:15, 29 September 2020 (UTC)
- All of the details that you miss are in FM_broadcasting and specifically FM_broadcasting#Stereo_FM. Gah4 (talk) 18:17, 29 September 2020 (UTC)
thanks. This seems a bit cumbersome having three overlapping articles. I'm not really sure the best approach to clean it up though. Gjxj (talk) 19:13, 29 September 2020 (UTC)
- I suppose, but they are a little different. This one describes the frequency bands, and especially how they differ between countries. Others describe the what goes into the signals. It doesn't seem too unreasonable to me. Gah4 (talk) 02:17, 30 September 2020 (UTC)
tails
The articles says: Normally each channel is 200 kHz (0.2 MHz) wide, and can pass audio and subcarrier frequencies up to 100 kHz. For AM, there is a nice relationship between modulation frequency and bandwidth. Not so easy for FM. As a first (or maybe zeroth) approximation, it is modulation bandwidth plus deviation, times two. Otherwise, the tails on FM go to infinity. Fortunately they decay fast enough that they can actually be used. Gah4 (talk) 00:20, 20 June 2023 (UTC)
FM at ANY frequency? Not.
The article claims that FM may occur at any frequency (of EMR). This is wrong. Maybe I'm being too pedantic, but a single frequency can be amplitude increased or decreased but not (frequency) "modulated". That is, frequency modulation, by definition, involves more than a single frequency.* FM by definition involves a frequency *band*. (Although I suppose it would be possible to have a discrete set (non-continuous) of frequencies over which the signal information passed). Ignoring the difficulties in having a single frequency receiver (even emitted by an ideally 'pure' single frequency emitter) the emr won't stay that way during propagation; at least, not on planet Earth. The other problem is that we aren't capable of frequency modulating "any" emr. Gamma rays? How about EMR with a wavelength of 1 million miles? etc. We're quite limited to the frequency ranges of EMR that we can propagate economically (thru the atmosphere, from point to point on the surface). *going from a single frequency A to a single frequency B *could* be termed a "frequency modulation"... 98.21.213.85
- FM is most commonly given as a carrier frequency with zero modulation, which is often the center of the band. So, I would take the at any frequency statement to mean the unmodulated, or otherwise, frequency. Gamma rays can be frequency modulated using Doppler shift, as is commonly done for Mössbauer spectroscopy. It is usual to keep the lower end of the band above zero, which does limit at the low frequency side. For the case of two frequencies, common for digital signals, it is instead called Frequency-shift keying. (That works for more than two, as long as it is a discrete number.) Gah4 (talk) 00:42, 9 February 2024 (UTC)