Talk:Rotary dial

Initial comments
Well I see now that someone just corrected it from "two" to "three inches in diameter"--better but still not quite there, I think. All the ones I saw (which were all for domestic use) were about 4 inches in diameter. I do have a ruler in front of me, unfortunately I don't have a rotary phone handy for measurement. --KQ


 * don't have a rotary phone handy for measurement !!!


 * I too have a ruler and also six phones with rotary dials (all of them produced for the UK phone system - one of them still connected to it!). They are all 78mm in diameter.
 * I am currently fuming at the way the Americans have created lots of articles Area code xxx. As though the rest of the world did not have area codes (and as though there were no area codes for purposes other than telephony). So I am not minded to translate 78mm.
 * But reluctantly I will tell you that 78mm is near enough to 3 inches to suggest that the original drawings (which would have used Imperial) specified exactly 3 inches.
 * RHaworth 10:09, 2005 Jan 6 (UTC)


 * I'm sorry, but isn't this what you would call "original research"? --Foot Dragoon 22:30, 21 October 2006 (UTC)


 * The first completely round (initially called "two wire system") telephone dials were 2 3/4 inches in diameter. The first automatic switching system installed in the U.K. was at Epsom, and since it used American equipment, the first dials used in the U.K. were also 2 3/4 inches in diameter.


 * Around 1918-1920 the American standard was changed to a full three inches (all manufacturers). The European standard at the same time settled at 80mm, which is a tiny bit larger than three inches.


 * One interesting point of trivia is that virtually all dials except for those made by Western Electric mute the dial clicks in the user's receiver by essentially short circuiting the receiver any time the dial is off-normal. Instead, Western Electric used an arrangement whereby the receiver was disconnected when the dial was off-normal.


 * --RogerInPDX (26Feb2007)

This statement could do with some rewriting: "The 1 is normally set at approximately 60 degrees clockwise from the uppermost point of the dial, or approximately at the 2 o'clock position, and then the numbers progress counterclockwise, with the 0 being at about 5 o'clock."

In fact the precise layout varies somewhat. The last part of that statement about the position of the zero is generally true in North American for Western Electric dials, so those who grew up in a Bell System area would have seen mostly such dials. But it was not always true for dials from other manufacturers, e.g. Automatic Electric dials, as found in many areas which were served by independent companies, generally had the zero at the "bottom" of the dial, around the 6 o'clock position. This was also true for the GPO dials on British telephones (and for the similar dials used in Australia & New Zealand, among other places).

And then there were other variations for "special" dials, such as the smaller types with movable finger stops on American Trimline phones. 87.113.176.128 (talk) 18:18, 1 June 2012 (UTC)

The statement that "Western Electric used an arrangement whereby the receiver was disconnected when the dial was off-normal" is incorrect, at least for WE 500-type dials. The dial's normally open ON contact muted the receiver by placing a short-circuit across it, as can be seen clearly in, for example, in http://www.beatriceco.com/bti/porticus/bell/pdf/bsp/502580406_we_500p_tel_sets.pdf and http://www.beatriceco.com/bti/porticus/bell/pdf/bsp/BSP_C32.535_we_500-type_sets.pdf V35b (talk) 22:35, 18 June 2012 (UTC)

Vertical service codes
This may be US-specific (I claim ignorance about that) but is it worth mentioning the different methods used to dial Vertical service codes using a rotary dial versus a touch tone keypad? (In Touch Tone the * is used as prefix, but with no * or # on a rotary dial, 11 is used.) - Keith D. Tyler &para; 18:37, 9 December 2005 (UTC)


 * That's certainly more a North American issue (as is the term "vertical service code"). Here in Britain, for example, there has never been any direct substitution of the "11" for "*" type.  There are a few cases where a specific numeric-only code has been assigned in parallel with a code which in the native programming of the switch uses * and/or #, but even that is rare.  An example would be the allocation of 1471 for readback of the last number to call on System X exchanges, in which the native code is actually *27#.  But BT has never advertised this latter code to the public, and has only ever listed 1471 since it was suitable for both DTMF and rotary customers from the outset.  87.113.176.128 (talk) 17:46, 1 June 2012 (UTC)

Removed "Tapping" (abuse)
This topic is more appropriate for the article on pulse dialing technology than it is for this article, so I moved it there. Cornlad 19:47, 9 August 2006 (UTC)

Dial (of telephone)
Is there a reason for both this "Rotary dial" article and the other Dial (of telephone) to exist, or should that one be merged into this one, or both into Telephone dial or something else? Jim.henderson 11:50, 6 July 2007 (UTC)
 * No. I've merged it into this one (except for the first paragraph and an ugly picture). Pro hib it O ni o ns  (T) 09:24, 19 July 2007 (UTC)


 * Why did you redirect it? A dial can mean BOTH a rotary dial as well as a dial pad. I-baLL 17:36, 30 July 2007 (UTC)


 * So, want to make it a disambiguator? As it is, that article says much, but almost all of it is also here.  Jim.henderson 17:48, 30 July 2007 (UTC)

Phasing out
The device was phased out from the 1970s onwards with the onset of Touch Tone dialing, which uses a telephone keypad instead of a dial.

Were the two directly connected? And is this potentially a case of regional variance? In the UK my family had keypad phones that generated pulses purchased in the late 1980s/early 1990s to replace dial phones but I don't recall tone phones taking off until later in the decade. (Or for that matter there being much of a drive to get the change over beyond automatic helplines annoying pulse phone users no end.) It would surprise me if the rise of the keypad was because of the bringing in touch tone, because it wouldn't make much sense to have a pule generating one on the market. Timrollpickering (talk) 11:01, 22 October 2008 (UTC)
 * The PMG released those keypad phones because people wanted them. And people wanted them because they were being seen in American movies. But the PMG couldn't give us touch-tone phones because we didn't have touch-tone exchanges. Most people didn't know there was a different technology, and some would have found it hard to believe. In AUS it was almost an article of faith that they had a modern phone system, one of the best in the world, and for most people that precluded any idea that the American phone system technology might be more advanced. Was it the same in the UK in the 80's?
 * Anyway yes, the touch pads followed the touch-tone. Specifically, the touch pad followed the introduction of the touch pad in the USA, which followed the introduction of touch-tone in the USA. —Preceding unsigned comment added by 218.214.18.240 (talk) 00:19, 6 February 2010 (UTC)


 * DTMF dialing became available with the TXE4 exchanges in the U.K. in the later 1970's, although it was a class-of-service option which had to be set up specifically. I believe the later TXE4A had DTMF registers available automatically for all lines.   But those were a pretty small percentage of the total number of exchanges in use at the time.  For the majority of people, DTMF dialing didn't really become an option until the 1980's as System X (and from about 1985 onward, System Y / AXE10) gradually displaced step-by-step, crossbar, and TXE2 systems.  The last SxS systems didn't disappear from the network until the 1990's, and unlike in the U.S., TouchTone converters were never added to these exchanges.  So as appears to be the case mentioned above for Australia, the Post Office would certainly rent you (at extra cost) a push-button phone in the 1970's, but for most people it was just a store-and-forward pulse dial arrangement, not DTMF.  91.125.81.99 (talk) 22:01, 1 June 2012 (UTC)
 * I remember for many years it was normal for push button phones in the UK to have a pulse/tone switch. I've also seen for sale rotary phones that support tone dialing. 130.88.108.187 (talk) 11:39, 3 April 2013 (UTC)

Converting call office dials to make free calls
What does this mean: "A relic of this system is found in differing emergency telephone numbers; the United Kingdom selected 999 due to the ease of converting call office dials to make free calls ('0' for the Operator was already free), whereas in New Zealand 1-1-1 was selected for the same reason"

You can put a lock onto a rotary dial. If you put the lock onto position 2 or 3, it is still possible to dial 111 on a standard phone. It is not possible to dial 0 or 9. This is the reverse of what is suggested.

Conversely, if you have a reversed dial, as NZ would have, it would be possible to allow 0 or 9 while not allowing 111. This is the reverse of what is suggested.

So what is a "call office dial", and how would it be "converted" to allow free calls to 999?

Incidently, in the 80's there was a lot of discussion on FIDO NET about where the numbers like 911 came from, and nobody knew. If any documentation has been found, I'd like to see it referenced. —Preceding unsigned comment added by 218.214.18.240 (talk) 00:04, 6 February 2010 (UTC)


 * This has nothing to do with those locks which were sold to fit the dials of a home telephone. In British terminology of the day, a call office was a telephone kiosk for public use, the famous red British "phone box" (a.k.a. a coinphone or payphone in North America).  The units which were in use at the time required the deposit of coins in order to make a call, and the dial would not operate (on digits 1 through 9) before the correct deposit was made (if you tried, no pulses would be sent and dial tone would just continue).  However, the call-office dials were equipped with extra contacts   (##)which permitted just the digit zero to be dialed without a coin deposit, so that callers could reach the operator for emergencies, to make a reverse-charge (collect) call etc. without coins.  It was a relatively easy matter to alter the contacts to allow both 9 and 0 to be dialed without coins (since they're next to each other at the end of the dial), thus allowing 999 calls to made without coins as well.  There were other reasons for adopting 999, which I'll outline below.


 * As for 911 in the U.S., all of the "n11" codes were reserved for various service facilities - 211 for long-distance in some places, 411 for information, 611 for repair service, 811 was often the telephone business office, etc. Some were not published numbers, but were used for telephone company test lines and the like.  So 911 fit the pattern of already reserved 3-digit service codes.  Why 911 and not some other "n11" number?   Possibly because it was the one least likely to already be in use in various places at the time (1967/1968).  Possibly because of the influence of the British 999.  And possibly because in rural areas served by SxS equipment, there were less likely to be subscriber numbers beginning with 9 than with some other number like 3 or 5, and without going into too much technical detail, it would thus be easier to make the necessary changes to implement 911 rather than 311 or some other code. (Those areas often used 113 for information, 114 for repair and so on rather than 411, 611 etc. for similar reasons.)

87.113.176.128 (talk) 19:51, 1 June 2012 (UTC)

(##) the extra contacts on the British phone box dial were operated by a special cam, which was extended to operate for 9 as well as 0 (and could be extended to 8 as well for other special service calls (in New Zealand 0 and 1 not 0 and 9) Hugo999 (talk) 05:15, 1 May 2013 (UTC)
 * And with the rollout of STD in the U.K., dials were modified to allow the digit 1 to be dialled as well as 9 & 0, so that calls to the operator could still be made without coins. (With STD conversion, 0 became the STD prefix and the code for operator was changed to 100.) 87.115.121.34 (talk) 17:01, 5 May 2014 (UTC)

New Zealand was Different
I read that the New Zealand phones had the 1 at the bottom and the 9 at the upper right. Perhaps this was a re-labelling with the mechanism underneath remaining the same. That would be why the number of ticks listed on this page for each number was different. But certainty is needed. 4.154.251.233 (talk) 12:46, 4 October 2010 (UTC)
 * Yes, New Zealand had dials in which zero was in the same place as the British/American dial, but the remaining digits 1 through 9 were reversed, hence why New Zealand adopted 111 as the emergency number instead of 999, and why Auckland was given STD code 09 (compare with the British code 01 which was allocated to London). The underlying mechanics were indeed the same, hence 9 on a New Zealand dial sent one pulse, 8 sent two pulses, 7 sent three pulses, etc., through to nine pulses for the digit 1.


 * There were other variations in the numbering in some countries, for example in Sweden 0 was in the first position, where 1 would be on British/American dials, then in sequence 1 through 9, the latter being where 0 was on British/American/New Zealand dials. So on Swedish dials, 0 sent one pulse, 1 sent two pulses, 2 sent three pulses, etc.


 * To help visualize it, here are the sequences on each of these dials counting counterclockwise in each case:


 * British/American 1-2-3-4-5-6-7-8-9-0
 * New Zealand 9-8-7-6-5-4-3-2-1-0
 * Sweden 0-1-2-3-4-5-6-7-8-9


 * 87.113.176.128 (talk) 18:08, 1 June 2012 (UTC)

History
The history section of this Rotary Dial article has more information about push-button phones than it does about rotary ones. 81.138.169.201 (talk) 12:52, 18 October 2010 (UTC)

UK dials
In the UK before All Figure Numbering and all over the country, dials were Lettered and then later Figures. The change happened from about the mid-late 1960s when the 746L instrument was replaced by the 746F version.

The vast majority of uses for Letter on dials were to allow calls, for example, to FINchley to be dialled as 346 and TIMe to produce 846 before all changed. In London the 3 digit scheme to use the letters in dials to indicate place names as above or other meaningful words to be used as names was limiting the system to about 320 combinations. After All Figure Numbering there would be a possible 880 such exchange codes in the then 01- telephone area.

The official line on why the UK has 999 as its Emergency access was explained as follows: in a stressful situation where the visibility was limited, light had failed or smoke was obscuring vision, the person stumbling over a working telephone could run their fingers down the dial until the 2nd finger rested against the finger stop. The 1st finger was then over the 9 and taking the 2nd finger out the way, 9 9 9 was easier to dial. Also as the UK had a large number of overhead spans it was thought that these might create loops and short disconnections in winds and emulate dial pulses. Spurious pulses might represent a few digits but not an organised repetition of the digit 9 which would result in repeated Emergency Calls. — Preceding unsigned comment added by Midnight Hour (talk • contribs) 20:04, 27 January 2012 (UTC)


 * The 746 telephone was introduced only around 1967, but the 706 which it replaced was also available with a numeric-only dial (706F) and one with letters (706L), as were the other variations of 700-series phones and the older 300-series etc. phones before them. Up until 1958, lettered dials were required only in the six director areas (i.e. those places with 7-digit numbering with the first three as letters) of London, Birmingham, Edinburgh, Glasgow, Liverpool, and Manchester, plus the immediately adjoining areas from which calls could be dialed directly into those cities.  Elsewhere, figures-only dials were used.


 * When STD commenced at the end of 1958, the original plan employed letters for the codes in most of the country, the legacy of which can still be seen in many of today's British area codes, e.g. 0PL2 for Plymouth (now 01752), 0AB4 for Aberdeen (now 01224), and 0NO3 for Norwich (now 01603).  So in those areas which got outgoing STD in the late 1950's/early 1960's, dials with letters were also required.  However, along with the change to AFN in London and the other large cities in the 1966-1968 period came the decision to drop the letters from STD codes as well.  So in those places which were outside the director cities and immediate areas and which did not have outgoing STD until after AFN, letters were never needed and dials were always figures-only types.  And unlike in North America where letters were generally retained on dials even after the various phone companies were no longer using them officially, as soon as letters were dropped from the official numbering system here, the Post Office saw no need to keep them on dials, and ALL dials from that point onward were figures-only types.


 * With regard to the choice of 999 in the 1930's, I've already mentioned the conversion of call-office dials in the section above as one reason for the choice. But there were other technical factors which undoubtedly played a part.  London used a step-by-step system with directors, the latter requiring three digits to be dialed into a register in order to translate the code into whatever routing digits were needed to get to the desired exchange, e.g. if you dialed WHItehall 1212 to call Scotland Yard, it was the WHI (944) part which was translated into whatever digits were needed to reach the Whitehall exchange from wherever in London you happened to be calling from.  There was an exception for dialing 0 for the operator, but for everything else, the directors needed three digits to "decide" what to do with the call.  Hence a 3-digit code was the simplest to implement for the new emergency number.  Since 9 has the letters WXY, the code 999 was vacant in all the director areas at the time, since there are few (sensible) words which can be formed with any combination of those letters at the start.


 * In areas outside the director cities (i.e. most of the country), various 9x codes were already in use at that time for calling general inquiries, phonograms (telegrams dictated by phone) and similar services, so it was relatively easy to add the connection for the new emergency number. And in many small exchanges in villages and rural areas, subscribers already dialed 9 first to call numbers in the nearby larger town, so the first 9 of 999 already sent the call to that town, where the operators were located.


 * So all in all, 999 really "ticked the boxes" all round for ease of implementation and in being memorable.  87.113.176.128 (talk) 20:18, 1 June 2012 (UTC)

New Zealand again
New Zealand got the “reverse-numbered” dials with the first Rotary system auto exchanges made by Western Electric in Antwerp; in 1919 Masterton and two exchanges (Courtenay Place and Wellington South) in the Wellington multi-exchange area. One theory in the Post Office (NZPO) was that the reverse-numbering was due to patent difficulties. Later when Christchurch and Dunedin got rotary auto exchanges, but their dials were “world standard” not reverse-numbered. These were later converted to the NZ-standard reverse-numbered dials!

Re touch-tone calling the first NEC crossbar exchanges in New Zealand from 1975 had DTMF calling, but that was only in special number groups using separate DTMF registers. Later the rotary-dial registers had Mitel converters (from Canada?) added so that all lines could have mixed DTMF and rotary-dial phones on them. There were plans to install the Mitel converters in older British step (Strowger) exchanges too, but that was a lot more work, and I don’t know if any were done.

Re the 7-digit letter-number telephone numbers used in North America and Britain, though there were doubts whether people could remember 7 digits, the main reason was the “big-city” problem like New York and London with a large number of manual exchanges to be converted gradually. Hence if you were on a manual exchange in London you would ask the operator for Mayfair 1234, or if on an auto exchange dial MAY 1234. New York got the Panel switch and London the Director telephone system instead of the Rotary system, although a couple of rotary exchanges were installed by the BPO and the Hull Corporation in England which ran the Hull phone systam bought rotary exchanges. I have a company reprint by Bell Telephone Mfg Co. of Antwerp (Rue Boudewyns) about the Hague Telephone network, run by the Municipality (1920s). Hugo999 (talk) 06:00, 1 May 2013 (UTC)
 * So far as I'm aware, there were never any DTMF/MF4 converters installed in BPO Strowger exchanges.  With regard to rotary in the Hull system, there were about six rotary switches installed there originally.  The last one was withdrawn from service in 1975 and sent to the Science Museum in London, although it seems that it might no longer be there.  87.112.135.112 (talk) 17:30, 6 May 2013 (UTC)

Fake rotary phones
i have seen quite a few phones which look like they have rotary dials, but in fact the finger wheel is fake, and the numbers are all push-buttons. i think the article should mention these imitation rotary dial phones, but i'm not sure where. 70.17.203.142 (talk) 00:12, 29 October 2013 (UTC)

My User with all contents
Contents up Paing Soe min 14:55, 17 November 2016 (UTC)  — Preceding unsigned comment added by Paing Soe min (talk • contribs)

Communicate
hello everyone 36.252.234.170 (talk) 10:22, 11 September 2022 (UTC)