The Music Network
This month Paul Gilby answers the fundamental question - what kind of modem do you need to access The Music Network?
The term 'modem' comes from Modulator DEModulator. Rather than going into the technical side of how a modem actually works, this article will focus on the more fundamental aspects of which modem to buy and what the differences are - a sort of buyer's guide if you like.
All modems work in a similar way and generally offer similar features. As with many electrical gadgets, the rule of thumb is the more you pay, the more features you get. At a basic level all modems, regardless of manufacturer, will send and receive data via the telephone lines at a variety of speeds and protocols. Don't let the jargon put you off, 'protocol' is just a descriptive term for the digital format in which the data is communicated. What concerns us most is speed, because the data protocol is a function of the software you use to drive the modem.
Speed is of the essence in the world of telecommunications because speed is money! Historically, modems became popular because of the advent of bulletin boards, which were generally single- or sometimes multi-user computer systems where you dialed up the computer via a modem and read messages or download programs. These systems usually ran at 300 baud (baud means 'bits per second', so 300 baud equals 300 bits of data per second) - rather a slow speed. As technology developed modems increased in transmission/reception speed to 1200 baud (and higher), prices fell, and things became more commercially attractive.
In Britain, the launch of Prestel saw the rapid spread of the ViewData modem, which operated at a special speed of 1200/75. This meant that you could receive data at 1200 baud, which was good and fast, but you could only transmit data at the tediously slow speed of 75 baud. As most users received data from Prestel rather than transmitted their own to the system, this was acceptable. However, when it comes to actually sending text messages, 75 baud is just uneconomical from both a cost and time point of view. The 1200 baud modems - often referred to as 1200/1200 to make it clear that they're equally fast in both directions - are realistically today's minimum acceptable standard if you are sending a lot of data yourself or participating in on-line conferences. You can use 300/300 modems, which offer a compromise between the slow and the fast. In fact, most 1200/75 and 1200/1200 modems will also operate at speeds of 300 baud.
The operating speed of the modem is important not just for the convenience of transferring data faster but also for economical reasons. That little extra investment of £70 or £80 in a fast modem can, believe me, actually save you money. How? It saves you money because you will spend less time connected to any on-line system you access and therefore will spend less on your telephone call and system connect time charges.
If you really want to go tearing around the data networks you could also consider a 2400/2400 baud modem (a real go-faster stripe job), but you'll only be able to use them with direct dial systems as British Telecom's PSS network is limited to a top speed of 1200 baud at present.
When reading about communications systems you will often come across the use of terms like V21 or V23. These 'V' numbers are a shorthand code for the modem speeds and are classified as follows:
V21 = 300/300
V23 = 1200/75
V22 = 1200/1200
V22 BIS = 2400/2400.
As the name suggests, this modem function will automatically dial a telephone number. It's similar to having a phone that stores all your regular numbers - but unlike a phone the numbers are generally stored as part of the communications software in your computer's memory rather than inside the modem. Having said that, some modems do have on-board storage facilities but you are not likely to use it. Any modem with auto-dial immediately relieves you of the need to physically attach a telephone to the computer to dial the numbers, so you save having to either buy another phone or steal the one out of the bedroom (you do, of course, still need a phone socket to plug the modem into).
What an auto-dial modem does is to dial the number as instructed from your comms software and automatically connect you to the data system at the relevant speed. This makes connection to a system fast and efficient and is certainly recommended. It also means that you can programme your comms software to automatically log onto a system at an appointed time without you having to be present! (At SOS we regularly use this facility at night to download magazine articles sent to our various electronic mailboxes and store them on floppy disk ready for us to read/edit in the morning! Isn't technology wonderful?)
Modems come in two forms, either boxed for external stand-alone use or as a plug-in board for installation inside the computer, also approved or not approved by BABT (non-approved means it hasn't received the familiar green sticker and been officially passed for connection to the UK phone system). On this point we'll say no more other than the non-approved ones are normally the cheapest.
If you own an Atari ST, Apple Mac (Plus/SE), BBC or Commodore Amiga 500 computer then you are going to have to use an external modem. Most units are mains powered, though some do run on batteries, and they plug into your computer via the serial/RS232 connector. The advantage of an external modem is that you can use it with a variety of different computers and it will probably be just as suitable if you upgrade your computer at a later date.
Internal modems are generally for use in PC compatibles, Amiga 2000 and Macintosh II computers and plug into one of the expansion slots. They are unobtrusive and take their power directly from the computer itself, and therefore offer several advantages - they leave your serial port connector free, save you buying a serial cable, don't use up another socket in your mains power board, and don't clutter up your work surface. The disadvantage is that you can only use the modem in a computer with suitable slots, and if you upgrade to a different computer later on you will probably need to buy a different modem.
You can buy some pretty cheap external modems for around £80 which only run at 300 and 1200/75 speeds. Better quality modems of this type would be the Pace Nightingale at £98, the Pace Linnet at around £140 or the Miracom Miracle WS4000 at £130. If you want to splash out on a 1200/1200 model, you might consider the Pace Linnet 1200 at £230, Miracle WS3000 at £290 or Amstrad SM2400 at £249. All these models are BABT approved. If you want a non-approved modem, there are plenty advertised in the computer magazines and you might take a look at such names as the Worldport 1200 from America, or some of the Taiwanese units.
On the internal modem front, the same names crop up. From Pace comes the Linnet Card, offering 1200/75 at £136, and the Linnet 1200 Card at £240, Miracle Keycard 3000 at £289, Amstrad MC2400 at £199, and the Dataflex Stradcom at around £169.
Finally, if you are interested in a 2400 baud modem, an external one in the shape of the Pace Series 4 2400S will cost around £530, an internal card from Miracom around £379, but good old Amstrad save the day with their MC2400 at £199.
Selecting a modem is fairly straightforward: first decide whether you need an external or internal model, then consider which features and speeds you require or can afford. If you can't quite stretch to a 1200/1200 unit then you should at least buy something which includes an auto-dial facility. There's no worry about general quality of performance, as they should all do the job admirably. What differences there are in performance specifications come down to how good the modem is at coping with noisy telephone lines and how good it is at maintaining a connection in bad conditions. Generally speaking, approved models are better than non-approved. One final point, regardless of your computer, almost without doubt any modem will be compatible and certainly none of the big names mentioned will cause any problems.
Next month we'll look at some popular communications software for various computers and explain how you can put the real power of The Music Network to work through its easy-to-use data transfer facilities that let you tap into the world of MIDI sound files and download them straight into your computer.
The Music Network, (Contact Details).