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123 votes
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Why did modems have speakers?

Much of this has been covered by previous answers, but to try to summarize: Adding a speaker was cheap and easy. The additional parts were standard, reliable, and inexpensive. It provided rich, ...
jeffB's user avatar
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110 votes
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What technological factors drove the rise of "high-speed" modems in the early 1990s?

Up to 9,600 baud it's just iterative application of fairly straightforward analogue-domain ideas as and when standards emerge. Then there's a significant improvement on the digital side that bumps to ...
Tommy's user avatar
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64 votes

Why did modems have speakers?

Not all modems from back in the day had speakers, for example an early popular modem was the Hayes Micromodem II (available for Apple ][ and S-100 machines) and it did not have a speaker. But the ...
bjb's user avatar
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33 votes
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What was the technical reason behind the octal digits used for CompuServe User IDs?

It appears to be a legacy from TOPS-10. The easy part: octal was more popular in the 60s and 70s in general, but especially at DEC, which produced a number of 18-bit machines; the 3 bits per symbol ...
hobbs's user avatar
  • 5,092
33 votes

How can I construct a dial-up network in my home, purely for the kicks?

A/the correct solution would be to set up some sort of small local PBX. In the spirit of retro you can probably score an analogue PBX for not very much money and the mechanical ones are arguably even ...
pndc's user avatar
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32 votes

Why did modems have speakers?

So why were modem speakers such a persistent feature, and "fixture" of the time? Three basic reasons: Adding a simple amplifier and a speaker is the most easy way to handle unexpected situations In ...
Raffzahn's user avatar
  • 226k
28 votes
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What exactly were those large orange chips on the Hayes Micromodem II interface card?

The 207C300 and 207C400 are "active filters for use with modems." They were manufactured by Sprague. I found an advertisement for them in Electronic Design magazine, volume 26, number 4, ...
Wayne Conrad's user avatar
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27 votes

Why was Wireplay "faster and more reliable" than dial-up Internet, since they both used the same hardware?

This article from British Telecom says Wireplay launched in June 1996 as a way to host multiplayer games over a closed dial-up network. This is why it was "non-Internet": All players were ...
Jim Nelson's user avatar
  • 3,773
23 votes

Why were "data modems" so much more expensive compared to "fax modems" back in the day?

I'll add a detail to the topmost answer. Data modems up to 2400bps used different frequency bands for transmit and receive. But why? Look at your telephone wire. There are only two wires going ...
d3jones's user avatar
  • 1,011
22 votes
Accepted

How did XBAND modems transmit game state?

Many games played over the Internet today use a client-server model, where the server has a full copy of the game state, and distributes appropriate pieces to the connected clients. Due to the ...
fadden's user avatar
  • 9,060
21 votes

Why did the Bell 103 modem use a data rate of 300 bps?

300 bits per second has the advantage that it is the lowest common multiple of both 50 and 60. These made it easier to use the power line frequency (50 Hz in Europe, 60 Hz in USA) to synchronise the ...
John's user avatar
  • 211
21 votes

Why were "data modems" so much more expensive compared to "fax modems" back in the day?

Fax machines use distinct frequency ranges for upstream and downstream transmission, with one direction receiving the vast majority of the bandwidth. Computer modems at 9600 and higher baud rates ...
supercat's user avatar
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21 votes

Why was Wireplay "faster and more reliable" than dial-up Internet, since they both used the same hardware?

I was the architect for BT Wireplay from 1995-2000 and am one of the co-authors of the patented network protocol. Essentially @hobbs answer is correct, in that 90s Internet links were often highly ...
Phil Ashby's user avatar
20 votes
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What was the service offered by US Sprint for long distance data connections in the late 1980's?

It sounds like what you're looking for is Telenet (renamed to "Sprintnet" when Sprint acquired it) or Tymnet. Tymnet did not survive and Sprintnet became part of what we now know as the Internet.
Greg Hewgill's user avatar
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20 votes
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Why did the Bell 103 modem use a data rate of 300 bps?

10 CPS/110 Baud was the maximum rate these signals could be sent with acceptable sidebands using an all-mechanical system. 300 was 3 times the teletype speed, and that limit is set by the 4 kHz ...
Ferd's user avatar
  • 811
19 votes

Why Kansas City Standard (KCS/CUTS) differs from Bell 103/202/212 modem protocol?

They are different because they are meant for different use cases so they both work well for what they are meant for. One is suitable for real time data transmission between two distant equipment over ...
Justme's user avatar
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19 votes

Why was Wireplay "faster and more reliable" than dial-up Internet, since they both used the same hardware?

If they still use the same modem, and the same telephone wires, why is "not using the Internet" faster and more reliable for playing (supported) games "online"? The internet is a ...
hobbs's user avatar
  • 5,092
18 votes

Whatever happened to the janus protocol

Short answer: Because it was useless to begin with. For a more detailed answer the whole picture is needed: Back in the real old days modems were symmetrical. A V.21 modem split the line into two ...
Raffzahn's user avatar
  • 226k
18 votes

A kind of modem that let you make voice calls with a simultaneous data connection: what was it called?

The technologies being referred to are Analog Simultaneous Voice and Data (ASVD) and Digital Simultaneous Voice and Data (DSVD), both of which become available in consumer-grade modems sometime around ...
Noel Whitemore's user avatar
15 votes

Why did the Bell 103 modem use a data rate of 300 bps?

A very good first answer however I would also like to note that any data rates above 300bps could not be acoustically coupled and were direct connect modems only. And anything 33.6K and above ...
Bryan Manske's user avatar
14 votes

What exactly were those large orange chips on the Hayes Micromodem II interface card?

So my question is, what is the deal with these chips and why do they seem unique to this particular interface card? While the orange colouring is quite flamboyant, the use of hybrid circuits/modules ...
Raffzahn's user avatar
  • 226k
11 votes

What technological factors drove the rise of "high-speed" modems in the early 1990s?

The early 300 bps modems used frequency shift keying (FSK), whereby sound is generated at one frequency to represent a '0' and a different frequency to represent a '1'. Standards prescribed what ...
ch-'s user avatar
  • 111
11 votes

Why did modems have speakers?

I suspect it could be a holdover from the days when a modem was a box that connected between your terminal and your phone. The phone handset was used to dial the remote number; when you heard the ...
dave's user avatar
  • 35.9k
11 votes

Why did the Bell 103 modem specification use 1070Hz, 1270Hz, 2025Hz and 2225Hz?

Why were these specific frequencies chosen other than needing to fit into the voice band Erm, in the end it's all about fitting in the voice band of 300..3400 Hz. For one, 1 kHz and 2 kHz are almost ...
Raffzahn's user avatar
  • 226k
10 votes

What was the technical reason behind the octal digits used for CompuServe User IDs?

CompuServe was initially a Time-sharing system utilizing original DEC PDP-10 machines. You would log in as a regular system user and run your programs. The credentials of these systems consisted of ...
Christian Mund's user avatar
10 votes

How was parity used with modems?

By the time I got my first analog modem, around 1980, my experience was the same as yours. Even and odd parity on 7-bit data was available, but almost all the BBSs featured 8N1. (The modems even still ...
RichF's user avatar
  • 9,346
10 votes

Why did modems have speakers?

All the answers above have concentrated on outgoing calls but modems also took incoming calls and, because phone lines were expensive, it was unusual to have multiple lines for fax, data, and voice. ...
Dave Keene's user avatar
9 votes

Creating Null Modem Connection between two C64s?

"Null modem cable" may not quite be a misnomer but is potentially misleading: it is a cable that connects two computers via their serial ports without modems. It's not a null cable for modems, it's ...
Tommy's user avatar
  • 37.3k
9 votes
Accepted

Cartridge modems - was the Vic-20 a special case?

I thought the RS-232 port on the Vic-20 was completely separate from the cartridge port, so a thing had to be plugged into one or the other, and if the modem was plugged into the latter then it could ...
Raffzahn's user avatar
  • 226k

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