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![]() | 56 kbit/s modem was nominated for deletion. The discussion was closed on 26 June 2014 with a consensus to merge. Its contents were merged into Modem. The original page is now a redirect to this page. For the contribution history and old versions of the redirected article, please see its history; for its talk page, see here. |
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Several dozen discussions going back to 2006 were moved to Talk:Modem/Archive_1 after I read each one and concluded that they were irrelevant or already resolved. The ones remaining on this page are in my opinion still open issues which should be addressed. Gravislizard ( talk) 15:55, 14 August 2020 (UTC)
I started a section on bonding modems (aka inverse multiplexing modem). Their is more info I did not add in the link I provided in the references section if anyone wants to add to or improve my wording in the section. -- Cab88 13:34, 6 March 2007 (UTC)
This article is hard to read and certain sections repeat eg 'V90' and 'Using digital lines and PCM'. The article gives greater coverage to voiceband modems than other modem types such as DSL modems, due to the many developments over the last 40 years. The descriptions of the variants of voiceband modems is now largely of historic interest. The article does not descibe the relationship between modems and networks, such as todays internet. For example a voiceband modem network typically used to be two identical modems over an analogue voice circuit but nowadays is typically a wide range of different 56k modems connecting over a digital PSTN to a shared central modem server. The section on 'Popularity' refers to using 56k voiceband modems to access the internet, obviously DSL modems are gaining in popularity. A better structure for this article is needed. John a s ( talk) 23:23, 12 January 2008 (UTC)
This topic somehow seems to have been omitted from the article. Some time ago, I read about "Wybrecht" and "Weinbrecht" modems; both were misspellings of the name of a born-deaf engineer, Robert Weitbrecht, who worked to establish TTY/TDD technology. (By all means, Google on his name!)
Apparently, TTY/TDDs were developed quite early compared to modems for use with computers, and their technical specifications differ in many respects from those of computer modems, although they operate on the same principles (FSK). There's more at {typical header}911broadcast.com/tech-emergency_technology_54.htm (a blacklisted Web site, unfortunately; do be careful!) for the details. There's a table there, although it doesn't specify start and stop bit timings.
Fortunately, modern technology makes compatibility between TTY/TDD traditional protocols and modern modem protocols affordable to many; the v.18 standard [1] specifies this. This standard also permits successful international use of TTY/TDDs.
I hope somebody else will pick up this thread and incorporate it into the article; I'm out of energy, for now. Regards, Nikevich ( talk) 09:28, 1 February 2011 (UTC) Best regards,
This article has multiple ambiguities, errors and omissions.
The terms "broadband" and "wideband" are time dependent; at one time they meant 56Kbps with a V.35 DCE/ DTE connection. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 13:05, 12 April 2020 (UTC)
The acoustic coupler was not the only option for connecting your own modem; you could use a conventional modem connected via a DAA. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 13:05, 12 April 2020 (UTC)
Hayes was not the first to provide a modem with the ability to place calls; they were, however the first to do so on an inexpensive modem. A dial interface was part of, e.g., X.21. Also, automatic calling units were available much earlier. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 13:05, 12 April 2020 (UTC)
@ Gravislizard:The Data Auxiliary Set 801A (Automatic Calling Unit)] and Data Auxiliary Set 801C (Automatic Calling Unit) were not third party. The linked documents are from 1965; I don't know whether that is when Western Electric (AT&T) started offering them or whether they are older.
By 1988 there was X.21, which did not require an ACU. Prior to that, I recall there being modems with autodial capability, but I don't recall whether they used the RS-232 secondary channel, a second RS-232 connection or something else. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 00:48, 14 August 2020 (UTC)
The History section discusses both dial-up and leased line modems, but it is subsidiary to Dial-up modem. Either it should be split or it should be promoted to a section of its own. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 00:17, 11 August 2020 (UTC)
The article does not explain the difference between synchronous and asynchronous modems and it doesn't mention the ubiquitous 408A and 408B. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 13:05, 12 April 2020 (UTC)
I found the 56k / v.90/v.92 section completely incomprehensible and rewrote it. The first paragraph appeared to be passages on several different topics that had been pasted in between each other, rendering the whole thing impossible to follow.
I split out the early 56k and standards-based 56k modems into separate subsections, organized the info and clarified dates, and most notably *removed* the passage on telco digital line restrictions. It's perhaps relevant, but is also perhaps a bit too specific to mean much in this context.
I originally stated here that the other page, "56kbit/s line," was a "main article" on the topic of 56k modems since it was linked as such, but after reading it it appears to be about an entirely different subject (essentially a stub that should probably be rolled into the DS0 article), so I've removed that link from this article as irrelevant, and am currently composing a summary of what the digital signaling paragraph was trying to say, based on references. Gravislizard ( talk) 21:21, 29 June 2020 (UTC)
Shouldn't the article mention automatic calling units such as the 801A and 801C? Does anybody have the dates for the 801A and 801C? Shmuel (Seymour J.) Metz Username:Chatul ( talk) 12:34, 10 August 2020 (UTC)
56k modems were in use for decades before the modems mentioned in Modem#Early 56k. The section should be called something like "Early 56k dial modems".
There really ought to be a section on the 4-wire modems in at least the range 1200 bps to 56k bps, e.g., 202C, 408A. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 12:50, 10 August 2020 (UTC)
Notes
Modem#Terminology states The term "modem" is often partially inaccurate when applied to broadband.
. However, a modem that performs other functions is still a modem. Further separate modems and routers are common in, e.g., cable modems,
FIOS. I certainly agree that there are a lot of combined units in use, but I don't believe that the term inaccurate is justified.
Shmuel (Seymour J.) Metz Username:Chatul (
talk) 19:04, 11 August 2020 (UTC)
For several reasons, broadband modems are almost always full-fledged network routers.is also dubious even for cable and incorrect for FIOS. Verizon installs an ONT and you need to either provide a router or obtain one from Verizon.
I'd like to add some synchronous modems to the table in #Evolution of dial-up speeds, but don't know what modulation techniques they use, or even the baud rates. Also, I know that there was a 2400 bps DataPhone circa 1962 but have no idea what the model or modulation techiques were. Can anybody fill in the gaps? Thanks.
Vendor | Model | S/L/W | bps | baud | Modulation |
---|---|---|---|---|---|
Western Electric | 202C1 | Switched | 1200 | ? | ? |
Western Electric | 202C2 | Switched | 1200 | ? | ? |
Western Electric | 202D1 | Leased Line | 1200 | ? | ? |
Western Electric | 202D2 | Leased Line | 1200 | ? | ? |
Western Electric | 201A3 | Leased Line Switched |
2000 | 1000 | PSK |
Western Electric | 201A4 | Leased Line Switched |
2000 | 1000 | PSK |
Western Electric | 201B1 | Leased Line | 2400 | 1200 | ? |
Western Electric | 201B2 | Leased Line | 2400 | 1200 | ? |
Western Union | 2241A | Wideband | 2400 | ? | ? |
Western Electric | 208A | Leased Line | 4800 | 1600 | DPSK 8 phase |
Western Electric | 208B | Switched | 4800 | 1600 | DPSK 8 pase |
Western Electric | TELPAK A | Wideband | 19,200 40,800 50,000 230,400 |
? | ? |
Shmuel (Seymour J.) Metz Username:Chatul ( talk) 15:50, 12 August 2020 (UTC)
@
Gravislizard and
Mvqr:I found some data on Jack L. Douglass (1984),
Applied Data Communications Handbook (PDF), Universal Data Systems, Motorola Inc.;
bitsavers
Fax modems can certainly transmit and receive documents that never were and never will be on paper, but [[efax]] redirects to Internet fax. Either the text here should be changed or Internet fax should be changed to define the term efax in a general fashion. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 01:13, 13 August 2020 (UTC)
Given the size of the dial-up modem subsection, I suggest we split it off to Dial-up modem and remove the redirect from that page. It's certainly enough content for its own article, and adding even more information (possible, given the enormous history of dial-up) could become more practical if we did this. I believe this article would retain enough content to stand on its own, would be more accessible without the enormous preface on dial-up, and would make room for more specific information on the general topic. I think this qualifies on its own merits, but I'm a relatively new editor and would like some consensus. Thanks! Gravislizard ( talk) 02:16, 13 August 2020 (UTC)
There is a case for either more granularity or less, so this is definitely something that needs to be hashed out as part of arriving at a consensus. Of course, if there is a consensus to not split then the question of granularity can be ignored. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 02:39, 13 August 2020 (UTC)
I've been working on cleaning up the history of dial modems but it's an enormous task. It appears to have been largely unchanged since 2007, but has always been a huge and somewhat unencyclopedic essay. I don't doubt that much of it is valid, but I feel the tone is a bit too informal, and much of it is I think very hard to source.
Assertions like "The 103A2 gave an important boost to the use of remote low-speed terminals such as the Teletype Model 33 ASR and KSR" or "Three U.S. companies became famous for high-speed versions of the same concept" seem very hard to prove (and indeed are uncited) but I'm reluctant to go through with a machete and rip them out wholesale.
Consequently, I've been doing a lot of medium-size edits that don't necessarily improve the quality of the article vis a vis the unverified facts, but attempt to clean up the information that's already here. For instance, I moved the subsection on acoustic couplers (and the one I created from it, on direct-connected modems) out of the history section because these are not specific points in history (as per the existing text which states that both were used concurrently,) and now those sections can be cited without depending on precise positions in the timeline, which is far easier.
I'm not sure that "history" is the best way to present all of this information. It may be more practical to make this article conform to Wikipedia standards by cutting back the history section to only cover the early era of modems (sage > bell 103 > development of third party products) and perhaps their rise and fall (increasing use by microcomputer users, then replacement by broadband) and reduce the rest of the history section to a simple breakdown of the various standards in a basic chronological order. Gravislizard ( talk) 16:10, 13 August 2020 (UTC)
The limited frequency range of telephone lines meant the symbol rate of modems was still only 600 baud.. That would have required 256 symbols, which would have been unheard of at the time.
@ Gravislizard:I've seen null modems listed as RS-232 crossover cables more often than as null modems; shouldn't the article at least mention the term?
BTW, after a search I was shocked to see that they are still being sold. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 02:47, 14 August 2020 (UTC)
Some dial modems required a conditioned line. Shouldn't there be a discussion of that in the article? I'd suggest that the details be held to a short paragraph plus a list of modems. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 10:02, 23 November 2020 (UTC)
I think the Telebit TrailBlazer is an important part of dialup modem history and I'm surprised that it is missing. There is a good description of the technology on its own page: /info/en/?search=Telebit Could someone knowledgable add some content here based on that? — Preceding unsigned comment added by 86.171.61.52 ( talk) 19:19, 6 September 2022 (UTC)
This point is made in regards to the discussion regarding is an ONT a modem? Whilst they perform a similar function, modems are typically devices that transmit signals over copper based networks whilst an ONT is used in fiber optic networks. An ONT is not a modem because fiber has no carrier wave. [1] This is not to be confused with a fibre optic modem (FOM).
ONT is a fiber-optic modem. -- Shmuel (Seymour J.) Metz Username:Chatul ( talk) 16:54, 16 April 2024 (UTC)
This is the
talk page for discussing improvements to the
Modem article. This is not a forum for general discussion of the article's subject. |
Article policies
|
Find sources: Google ( books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL |
Archives: 1 |
![]() | 56 kbit/s modem was nominated for deletion. The discussion was closed on 26 June 2014 with a consensus to merge. Its contents were merged into Modem. The original page is now a redirect to this page. For the contribution history and old versions of the redirected article, please see its history; for its talk page, see here. |
![]() | Text and/or other creative content from this version of Talk:56 kbit/s modem was copied or moved into Modem#Using digital lines and PCM (V.90/92) with this edit. The former page's history now serves to provide attribution for that content in the latter page, and it must not be deleted as long as the latter page exists. |
![]() | This ![]() It is of interest to multiple WikiProjects. | |||||||||||||||||||||||||||||||||||||||||||||||||||||
|
![]() | This article links to one or more target anchors that no longer exist.
Please help fix the broken anchors. You can remove this template after fixing the problems. |
Reporting errors |
Several dozen discussions going back to 2006 were moved to Talk:Modem/Archive_1 after I read each one and concluded that they were irrelevant or already resolved. The ones remaining on this page are in my opinion still open issues which should be addressed. Gravislizard ( talk) 15:55, 14 August 2020 (UTC)
I started a section on bonding modems (aka inverse multiplexing modem). Their is more info I did not add in the link I provided in the references section if anyone wants to add to or improve my wording in the section. -- Cab88 13:34, 6 March 2007 (UTC)
This article is hard to read and certain sections repeat eg 'V90' and 'Using digital lines and PCM'. The article gives greater coverage to voiceband modems than other modem types such as DSL modems, due to the many developments over the last 40 years. The descriptions of the variants of voiceband modems is now largely of historic interest. The article does not descibe the relationship between modems and networks, such as todays internet. For example a voiceband modem network typically used to be two identical modems over an analogue voice circuit but nowadays is typically a wide range of different 56k modems connecting over a digital PSTN to a shared central modem server. The section on 'Popularity' refers to using 56k voiceband modems to access the internet, obviously DSL modems are gaining in popularity. A better structure for this article is needed. John a s ( talk) 23:23, 12 January 2008 (UTC)
This topic somehow seems to have been omitted from the article. Some time ago, I read about "Wybrecht" and "Weinbrecht" modems; both were misspellings of the name of a born-deaf engineer, Robert Weitbrecht, who worked to establish TTY/TDD technology. (By all means, Google on his name!)
Apparently, TTY/TDDs were developed quite early compared to modems for use with computers, and their technical specifications differ in many respects from those of computer modems, although they operate on the same principles (FSK). There's more at {typical header}911broadcast.com/tech-emergency_technology_54.htm (a blacklisted Web site, unfortunately; do be careful!) for the details. There's a table there, although it doesn't specify start and stop bit timings.
Fortunately, modern technology makes compatibility between TTY/TDD traditional protocols and modern modem protocols affordable to many; the v.18 standard [1] specifies this. This standard also permits successful international use of TTY/TDDs.
I hope somebody else will pick up this thread and incorporate it into the article; I'm out of energy, for now. Regards, Nikevich ( talk) 09:28, 1 February 2011 (UTC) Best regards,
This article has multiple ambiguities, errors and omissions.
The terms "broadband" and "wideband" are time dependent; at one time they meant 56Kbps with a V.35 DCE/ DTE connection. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 13:05, 12 April 2020 (UTC)
The acoustic coupler was not the only option for connecting your own modem; you could use a conventional modem connected via a DAA. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 13:05, 12 April 2020 (UTC)
Hayes was not the first to provide a modem with the ability to place calls; they were, however the first to do so on an inexpensive modem. A dial interface was part of, e.g., X.21. Also, automatic calling units were available much earlier. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 13:05, 12 April 2020 (UTC)
@ Gravislizard:The Data Auxiliary Set 801A (Automatic Calling Unit)] and Data Auxiliary Set 801C (Automatic Calling Unit) were not third party. The linked documents are from 1965; I don't know whether that is when Western Electric (AT&T) started offering them or whether they are older.
By 1988 there was X.21, which did not require an ACU. Prior to that, I recall there being modems with autodial capability, but I don't recall whether they used the RS-232 secondary channel, a second RS-232 connection or something else. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 00:48, 14 August 2020 (UTC)
The History section discusses both dial-up and leased line modems, but it is subsidiary to Dial-up modem. Either it should be split or it should be promoted to a section of its own. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 00:17, 11 August 2020 (UTC)
The article does not explain the difference between synchronous and asynchronous modems and it doesn't mention the ubiquitous 408A and 408B. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 13:05, 12 April 2020 (UTC)
I found the 56k / v.90/v.92 section completely incomprehensible and rewrote it. The first paragraph appeared to be passages on several different topics that had been pasted in between each other, rendering the whole thing impossible to follow.
I split out the early 56k and standards-based 56k modems into separate subsections, organized the info and clarified dates, and most notably *removed* the passage on telco digital line restrictions. It's perhaps relevant, but is also perhaps a bit too specific to mean much in this context.
I originally stated here that the other page, "56kbit/s line," was a "main article" on the topic of 56k modems since it was linked as such, but after reading it it appears to be about an entirely different subject (essentially a stub that should probably be rolled into the DS0 article), so I've removed that link from this article as irrelevant, and am currently composing a summary of what the digital signaling paragraph was trying to say, based on references. Gravislizard ( talk) 21:21, 29 June 2020 (UTC)
Shouldn't the article mention automatic calling units such as the 801A and 801C? Does anybody have the dates for the 801A and 801C? Shmuel (Seymour J.) Metz Username:Chatul ( talk) 12:34, 10 August 2020 (UTC)
56k modems were in use for decades before the modems mentioned in Modem#Early 56k. The section should be called something like "Early 56k dial modems".
There really ought to be a section on the 4-wire modems in at least the range 1200 bps to 56k bps, e.g., 202C, 408A. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 12:50, 10 August 2020 (UTC)
Notes
Modem#Terminology states The term "modem" is often partially inaccurate when applied to broadband.
. However, a modem that performs other functions is still a modem. Further separate modems and routers are common in, e.g., cable modems,
FIOS. I certainly agree that there are a lot of combined units in use, but I don't believe that the term inaccurate is justified.
Shmuel (Seymour J.) Metz Username:Chatul (
talk) 19:04, 11 August 2020 (UTC)
For several reasons, broadband modems are almost always full-fledged network routers.is also dubious even for cable and incorrect for FIOS. Verizon installs an ONT and you need to either provide a router or obtain one from Verizon.
I'd like to add some synchronous modems to the table in #Evolution of dial-up speeds, but don't know what modulation techniques they use, or even the baud rates. Also, I know that there was a 2400 bps DataPhone circa 1962 but have no idea what the model or modulation techiques were. Can anybody fill in the gaps? Thanks.
Vendor | Model | S/L/W | bps | baud | Modulation |
---|---|---|---|---|---|
Western Electric | 202C1 | Switched | 1200 | ? | ? |
Western Electric | 202C2 | Switched | 1200 | ? | ? |
Western Electric | 202D1 | Leased Line | 1200 | ? | ? |
Western Electric | 202D2 | Leased Line | 1200 | ? | ? |
Western Electric | 201A3 | Leased Line Switched |
2000 | 1000 | PSK |
Western Electric | 201A4 | Leased Line Switched |
2000 | 1000 | PSK |
Western Electric | 201B1 | Leased Line | 2400 | 1200 | ? |
Western Electric | 201B2 | Leased Line | 2400 | 1200 | ? |
Western Union | 2241A | Wideband | 2400 | ? | ? |
Western Electric | 208A | Leased Line | 4800 | 1600 | DPSK 8 phase |
Western Electric | 208B | Switched | 4800 | 1600 | DPSK 8 pase |
Western Electric | TELPAK A | Wideband | 19,200 40,800 50,000 230,400 |
? | ? |
Shmuel (Seymour J.) Metz Username:Chatul ( talk) 15:50, 12 August 2020 (UTC)
@
Gravislizard and
Mvqr:I found some data on Jack L. Douglass (1984),
Applied Data Communications Handbook (PDF), Universal Data Systems, Motorola Inc.;
bitsavers
Fax modems can certainly transmit and receive documents that never were and never will be on paper, but [[efax]] redirects to Internet fax. Either the text here should be changed or Internet fax should be changed to define the term efax in a general fashion. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 01:13, 13 August 2020 (UTC)
Given the size of the dial-up modem subsection, I suggest we split it off to Dial-up modem and remove the redirect from that page. It's certainly enough content for its own article, and adding even more information (possible, given the enormous history of dial-up) could become more practical if we did this. I believe this article would retain enough content to stand on its own, would be more accessible without the enormous preface on dial-up, and would make room for more specific information on the general topic. I think this qualifies on its own merits, but I'm a relatively new editor and would like some consensus. Thanks! Gravislizard ( talk) 02:16, 13 August 2020 (UTC)
There is a case for either more granularity or less, so this is definitely something that needs to be hashed out as part of arriving at a consensus. Of course, if there is a consensus to not split then the question of granularity can be ignored. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 02:39, 13 August 2020 (UTC)
I've been working on cleaning up the history of dial modems but it's an enormous task. It appears to have been largely unchanged since 2007, but has always been a huge and somewhat unencyclopedic essay. I don't doubt that much of it is valid, but I feel the tone is a bit too informal, and much of it is I think very hard to source.
Assertions like "The 103A2 gave an important boost to the use of remote low-speed terminals such as the Teletype Model 33 ASR and KSR" or "Three U.S. companies became famous for high-speed versions of the same concept" seem very hard to prove (and indeed are uncited) but I'm reluctant to go through with a machete and rip them out wholesale.
Consequently, I've been doing a lot of medium-size edits that don't necessarily improve the quality of the article vis a vis the unverified facts, but attempt to clean up the information that's already here. For instance, I moved the subsection on acoustic couplers (and the one I created from it, on direct-connected modems) out of the history section because these are not specific points in history (as per the existing text which states that both were used concurrently,) and now those sections can be cited without depending on precise positions in the timeline, which is far easier.
I'm not sure that "history" is the best way to present all of this information. It may be more practical to make this article conform to Wikipedia standards by cutting back the history section to only cover the early era of modems (sage > bell 103 > development of third party products) and perhaps their rise and fall (increasing use by microcomputer users, then replacement by broadband) and reduce the rest of the history section to a simple breakdown of the various standards in a basic chronological order. Gravislizard ( talk) 16:10, 13 August 2020 (UTC)
The limited frequency range of telephone lines meant the symbol rate of modems was still only 600 baud.. That would have required 256 symbols, which would have been unheard of at the time.
@ Gravislizard:I've seen null modems listed as RS-232 crossover cables more often than as null modems; shouldn't the article at least mention the term?
BTW, after a search I was shocked to see that they are still being sold. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 02:47, 14 August 2020 (UTC)
Some dial modems required a conditioned line. Shouldn't there be a discussion of that in the article? I'd suggest that the details be held to a short paragraph plus a list of modems. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 10:02, 23 November 2020 (UTC)
I think the Telebit TrailBlazer is an important part of dialup modem history and I'm surprised that it is missing. There is a good description of the technology on its own page: /info/en/?search=Telebit Could someone knowledgable add some content here based on that? — Preceding unsigned comment added by 86.171.61.52 ( talk) 19:19, 6 September 2022 (UTC)
This point is made in regards to the discussion regarding is an ONT a modem? Whilst they perform a similar function, modems are typically devices that transmit signals over copper based networks whilst an ONT is used in fiber optic networks. An ONT is not a modem because fiber has no carrier wave. [1] This is not to be confused with a fibre optic modem (FOM).
ONT is a fiber-optic modem. -- Shmuel (Seymour J.) Metz Username:Chatul ( talk) 16:54, 16 April 2024 (UTC)