Talk:DTMF

message: I replaced the audio clip in the article. The old clip (http://en.wikipedia.org/wiki/File:DTMF_trucking_push_to_talk_ID_example.ogg) involved some DTMF tones, but seemed to focus on something else. Jaho (talk) 22:03, 29 March 2010 (UTC)
thread_title:  Replaced audio clip 

message: According to the current article, DTMF was first introduced to the public at the NY World's Fair in 1964. It was, however, in full "field test" usage in multiple small towns in the US by then. Most notably, it was first used in Findlay Ohio in 1960 and then in Greensburg, PA in 1961. Is this distinct from a public "introduction" LotSolarin 09:03, 9 December 2006 (UTC)
thread_title:  History and Introduction 

message: I don't know what "number spelling" is properly called, but how about an explanation of the association of letters and phone digits, which is getting rarer these days but still sometimes used in advertising, like "1-800-RENTCAR"? I guess a new article would be appropriate for this subject, since this can of course also be done with pulse dialing?
:Telephone number has an appropriate section
:Jim.henderson 00:31, 13 December 2006 (UTC)
replies: text: Oh no it doesn't.   86.145.151.250 (talk) 17:36, 8 November 2013 (UTC)
thread_title:  "Number spelling" 

message: The article says: "With the widespread introduction of computers and bank machines, the phone keyboard has become 'oddball', causing mistakes."
I would remove 'bank machines' from that sentence, because they have the same layout as phone keypads.
Jim Habegger 192.131.239.250 17:07, 9 December 2005 (UTC)
replies: text: Besides which, I hardly think that "oddball" can legitimately be used to describe a keypad layout which is the norm on hundreds of millions of telephones worldwide.  87.113.45.147 (talk) 21:38, 19 August 2012 (UTC)
thread_title:  Bank Machines 

message: These images are so low quality as to be essentially useless. The waveform one doesn't actually show the waveforms, all you can see is 3 white blocks, and it's almost impossible to see the tones in the spectrum image. The images should be removed from the article or replaced with higher quality images that actually convey useful information. Jibjibjib 09:27, 17 January 2007 (UTC)
thread_title:  DTMF waveform and spectrum images 

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replies: text: Is it possibly to add something about sampling, analog to digital conversion and reconstruction of DTMF signals?  —Preceding unsigned comment added by 78.90.230.235 (talk) 15:26, 27 December 2008 (UTC)
replies: text: It is a rare unit, however it is one of the only production units to use all 16 tone combinations in the DTMF specification. Most just used the 12 most common and since this article is about the full DTMF specification and you can see a 12 button DTMF set most anywhere, it seemed appropriate. Also, the previous photo was crap. In retrospect, having it at the top is potentially confusing. Does anyone have a good shot of a 12 button? I'll see if I can dig one up. Lexlex (talk) 04:55, 3 October 2010 (UTC)
replies: text: And the earliest DTMF units released for customer use had only 10 buttons.  The 12-button pads with * & # added didn't become standard issue until later in the 1960's.  146.90.92.209 (talk) 12:07, 20 June 2013 (UTC)
thread_title: Image copyright problem with Image:Autovon keypad.jpg

message: Article says: "Due to DTMF over analog telephone lines in the voice-frequency band between telephone handsets and other communications-terminating devices and the switching center, the previously semiautomated system that needed human intervention from a telephone operator, who then dialed a sequence of MF digits that were then routed and switched via automation." Can anyone write this more clearly? I can't understand it at all - otherwise I'd have a go. --Northernhenge (talk) 22:39, 27 June 2010 (UTC)
thread_title:  Incomplete, over-complex sentence 

message: Great article, but in special tones section should be the Off-Hook Tone or at least a cross-reference to an already-existing Wikipedia article on such:  http://en.wikipedia.org/wiki/Off-hook_tone
I don't know how to insert references.  Feel free to do so.
It is true that the off-hook uses four tones, not two.  But still, if you make a special section for special tones it is such a bother that one special tone (off-hook) is missing when there is otherwise very complete coverage of everything else.
Missing the off-hook tone in the special tonse section aside, superb article.  I knew all the "what"s from books I had, but the why's and motivations -- that was new & quite nice.  — Preceding unsigned comment added by 12.71.173.3 (talk) 18:39, 16 August 2012 (UTC)
thread_title:  Something Missing in the Special Tones Section 

message: A single frequency can be produced from most landline telephones.  To get the row's frequency, chord (simultaneously push) two buttons from that row.  You will hear only a single sinewave -- the one for that row.  Similarly, chording two column buttons produces only the sinewave assigned to that column.
If you do these chordings whilst on a system that has menus (such as a voice mail system), be sure the chordings are exact; that is, make sure you don't have a single button only depressed (for 70+ ms), otherwise you will have activated that menu choice that corresponds to the number of the button.
The chording trick is a way to test fidelities throughout the system, from source (your landline phone) to playback (let's say you did the chording to a voice mail system).
But at home, in your earpiece, you can just do the chording to hear what each frequency alone sounds like.
Remember, chording doesn't work from cell phones and probably doesn't work from computerized / digital workplace phones.  — Preceding unsigned comment added by 12.71.173.3 (talk) 18:52, 16 August 2012 (UTC)
thread_title:  Hearing Just ONE of the two DTMF frequencies 

message: I am removing an incoherent paste which was linking introduction to the public of the push-button telephone to LD's technical problems.  Further, the source intended for backing the date of November 18, 1963 in the first push-button telephone article could not be verified. --Askedonty (talk) 08:24, 14 September 2013 (UTC)
thread_title:  Multifrequency signaling, LD introduction 

message: The word "Multi" is short for something. Simply by adding it to the beginning of another word would normally dictate the word is short for "Multiple". 
In this case to say DTMF stands for Dual Tone Multiple Frequency would be redundant. Dual Tone is a Multiple Frequency.
What the "Multi" in this case means is "Multiplex". Mean the "Mixing" of the Dual Frequencies into one sound wave.
So, DTMF stands for a Dual Tone Multiplex Frequency.  — Preceding unsigned comment added by 74.215.252.131 (talk) 15:52, 27 February 2020 (UTC)
thread_title:  What does "multi" mean? 

message: :The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review after discussing it on the closer's talk page. No further edits should be made to this discussion.
The result of the move request was: page moved.  wbm1058 (talk) 19:18, 15 March 2024 (UTC)
replies: text: Dual-tone multi-frequency signaling →  – Per WP:COMMONNAME and MOS:ACROTITLE, it is commonly called DTMF and the abbreviation is not commonly used for something else. PhotographyEdits (talk) 11:59, 21 February 2024 (UTC)

text: Agree - DTMF is the most common parlance in telecom documentation. Lexlex (talk) 21:04, 25 February 2024 (UTC)
thread_title:  Requested move 21 February 2024