TELECOMMUNICATIONS: How To Get Started
Kathy Yakal, Editorial Assistant
More and more people are using their personal computers to communicate with bulletin board systems, information services, mainframe computers, and other personal computers. How do you get started in telecommunications? What kind of software do you need? Here's an overview.
Anchor Automation's Volksmodem can interface with most personal computers via a separate cable. It is a direct-connect modem.Telecommunications has been big news lately. People are breaking into university systems and bank account files. They're even doing what some people said couldn't be done after WarGames came out: making some sort of contact with computers that monitor and control this country's defense system.
Translating Foreign Signals
In telecommunications, the information being sent from one computer to another travels over the telephone lines. Though this is the most efficient method available now, there is a problem: telephones and computers are based on different technologies. Phone systems are designed to filter out the very clicks and pops that computers use to communicate.
This is why you need a modem (MOdulator/DEModulator). This device modulates the computer's digital signals into analog signals, so the phone lines can carry them, and then demodulates them back into digital, so the computer on the other end can receive them. The modem serves as a translator.
There are two types of modems commonly used with personal computers. Acoustic modems have a set of soft rubber cups into which you insert the phone's handset. One cup contains a speaker, which generates audio tones, the other a microphone, which receives tones from the other modem.
Direct-connect modems plug directly into the telephone through a modular phone jack. Some, like the VICmodem, are cartridges that are plugged directly into a port on the computer. Others are stand-alone units about the size and shape of an eight-track cartridge tape which can be placed directly beneath the phone and plugged in. Some of these have a feature which allows you to switch from phone functions to modem functions. This spares you from having to keep connecting and disconnecting the modem when you want to use the phone to make a call.
Acoustic modems are generally less expensive but direct-connect modems generally offer a better connection, since the sound frequencies necessary for telecommunications are generated directly on the phone lines. Extraneous room noises can interfere when you're using an acoustic modem if the phone handset is not sealed very tightly in the cups.
Some computers come with a built-in modem. The Radio Shack TRS-80 Model 100 Portable Computer is an example. The modem functions and terminal software are contained inside the computer; all you need is a cable to start telecomputing.
Dumb Peripherals
If you turn your personal computer into a terminal when using a modem, how can it accomplish something as complicated as transmitting data to another terminal around the block or around the world? Your computer must be able to send and interpret bits in the pattern you want, or you'll just be sending and receiving nonsense. This is why you need special software for telecommunications.
Some terminal software comes on cassette, some on disk, and some in cartridge form. There are several terminal programs in this issue.
Matching Up
Also, a modem must be properly aligned with another modem before information transmission is possible. Both modems must be matched in several ways.
Baud rate is the number of bits being sent every second. This can vary from 110, which is what the old teletypes use, up to 9600. The faster the rate, the lower your phone bills. But sending information as fast as 9600 bits per second really tests the capabilities of the telephone system. In order to establish communications, you need to know the baud rate at which the system you are calling is operating so that you can set your terminal software to the same rate.
Another factor is duplexing. Full-duplex means being able to send and receive data at the same time. Half-duplex allows for only one-way communication. If this is not matched correctly to the system with which you are communicating, you may see double characters on your screen or none at all.
The Racal-Vadic VA3413 is an acoustic modem. The telephone handset is pushed into the soft rubber cups on the side.Some terminal software allows you to upload and download programs. Say you have a friend in another part of the country who just programmed a great game and wants to share it with you, but doesn't have a printer. If you both have the same kind of computer, and an appropriate terminal program, that program can be uploaded (sent) to you. What you will be downloading is ASCII code (numbers which represent all possible screen characters). Each character is received one at a time. Not all terminal software has this capability; make sure that yours does if you want to be able to upload and download to and from bulletin board systems, information services, or other personal computers.
Modem Manufacturers And Distributors Listed below are the manufacturers and distributors of the modems included in our buyer's guide, as well as those of the major information and news services. Anchor Automation Cermetek Microelectronics, Inc. Commodore Business Machines Emtrol Systems, Inc. Hayes Microcomputer Products, Inc. Microbits Peripheral Products, Inc. The Microperipheral Corporation Novation, Inc. Prentice Corporation Racal-Vadic TNW Corporation Universal Data Systems |
The World Of Telecomputing
Once you have the correct hardware and software for telecommunications, there is a great deal of information that you can access:
News and information services. CompuServe and The Source are two examples. Once you have purchased a subscription, you can call, type in your secret ID number or password, and have all kinds of information delivered to you immediately – news, sports, stock market reports. You can set up your own electronic mailbox so that messages can be left for you. CompuServe even has its own version of CB radio: You can get on-line with other people using the system and have a conversation.
Bulletin board systems. Offering some of the features of the major information services, there are hundreds of bulletin board systems set up in North America. Some of them are free, some require a membership fee. Most of them are designed to bring together people with common interests: owners of specific types of computers who want to share programs and help solve
News And Information Services Here are addresses and phone numbers for some of the major news and information services. New York Zoetrope publishes The Directory of On-Line Databases; you can get one by sending $29.95 plus $1.50 for shipping and handling to New York Zoetrope, 80 East 11th Street, New York, NY 10003. CompuServe Dow Jones Information Services The Source Telenet |
hardware or software problems, people involved in ham radio, film buffs – even people who want to find a date.
Personal business. It may be possible soon to attend to most of your personal needs with your personal computer. Periphonics, an Exxon affiliate, has developed an interface that permits a bank to link up with almost any personal computer for individual bank transactions. Shopping by mail is possible through the Burbank-based "Fantasy Plaza." Expect to see more services like this springing up.
Computer programs over the radio. It is possible to download computer programs from your radio. The Microperipheral Corporation has even developed a modem designed for reception of computer data from commercial radio stations. Though this is not a widespread use right now, radio stations and cable operations around the country may soon be following the lead of stations like KMPS in Seattle, which has been downloading computer programs by radio since March.
A Buyer's Guide To Modems The following chart lists features of several modems compatible with personal computers. We have tried to include as many as possible; any omissions do not represent an editorial judgment on their quality. If you need more information about a specific modem, consult the list of manufacturers and distributors. Here is a brief explanation of the categories on the chart:
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MODEM | Volksmodem | Mark VI | Mark VII | Mark X | Mark XII | Auto VIC 1650 | VIC modem | Info-Mate ZIZA | TRS-80 LYnx | |
Manufacturer/Distributor | Anchor Automation | Anchor Automation | Anchor Automation | Anchor Automation | Anchor Automation | Commodore Business Machines | Commodore Business Machines | Cermetek Micro-Electronics, Inc. | Emtrol Systems, Inc. | |
Compatibility | most personal computers | IBM-PC | RS-232 | Hayes-compatible | Hayes-compatible | Commodore 64 | VIC-20 and Commodore 64 | RS-232 | TRS-80 I, III | |
Communication Standard | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 212A | Bell 103 | Bell 103 | Bell 212A | Bell 103 | |
Coupling Method | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | |
Baud Rate | 300 | 300 | 300 | 300 | 300-1200 | 0-300 | 0-300 | 300/1200 | 300 | |
Duplexing | full/half | full/half | full/half | full/half | lull/half | full/half | full | full | full/half | |
Auto-Answer | no | yes | yes | yes | yes | yes | no | yes | yes | |
Auto-Originate | yes | yes | yes | yes | yes | yes | no | yes | yes | |
Self-Test | yes | no | no | no | no | no | no | yes | no | |
Carrier Detection Indicator | varies | tone | light | light | varies | LED | LED | light | LED | |
Power Supply | 9-volt battery | host computer | AC | 12-volt adapter | 12-volt adapter | host computer | host computer | AC | AC | |
Necessary Cables/Connectors Included? | no | plugs into computer | yes | yes | yes | plugs into computer | plugs into computer | yes | yes | |
Terminal Software Included? | no | yes | no | no | no | no | yes | no | yes | |
Warranty | lifetime | 2 years | 2 years | 2 years | 2 years | 90 days | 90 days | 1 year | 1 year | |
Price | $79.95 ($12.95 for cable) | $239 | $159.95 | $179.95 | $399 | $179.95 | $109.95 | $595.00 | $299.95 | |
MODEM | Apple Lynx | Hayes Micromodem 100 | Micromodem II | Stack Smartmodem 300 | Smartmodem 1200 | Smartmodem 1200B | MPP-1000C | Micro-connection 01 | Micro-connection R1 | |
Manufacturer/Distributor | Emtrol Systems, Inc. | Hayes Microcomputer Products, Inc. | Hayes Microcomputer Products, Inc. | Hayes Microcomputer Products, Inc. | Hayes Microcomputer Products, Inc. | Hayes Microcomputer Products, Inc. | Microbits | The Microperipheral Corp. | The Microperipheral Corp. | |
Compatibility | Apple I, II, II+ | S-100 bus | Apple | RS-232 | RS-232 | IBM-PC | Atari (no 850 needed) | Osborne | RS-232 | |
Communication Standard | Bell 103 | Ball 103 | Bell 103 | Bell 103 | Bell 103 & 212A | Bell 212A | Bell 103 | Bell 103 | Bell 103 | |
Coupling Method | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | |
Baud Rats | 300 | 45-300 | 110 or 300 | 0-300 | 0-300 & 1200 | 0-300 & 1200 | 300 | 300 | 300 | |
Duplexing | full/half | full | full | full/half | full/half | full/half | full/half | full/half | full/half | |
Auto-Answer | yes | yes | yes | yes | yes | yes | yes | no | no | |
Auto-Originate | yes | yes | yes | yes | yes | yes | yea | no | no | |
Self-Test | no | no | no | yes | yes | yes | no | no | no | |
Carrier Detection Indicator | LED | none | LED on board | LED | LED | on screen | tone | LED | LED | |
Power Supply | AC | host computer | host computer | AC | AC | AC | AC | AC | AC | |
Necessary Cables/Connectors Included? | yes | yes | yes | no | no | no | yes | yes | yes | |
Terminal Software Included? | yes | no | yes | no | no | yes | yes | no | no | |
Warranty | 1 year | 2 years | 2 years | 2 years | 2 years | 2 years | 1 years | 90 days | 90 days | |
Price | $299.95 | $399 | $409 | $289 | $609 | $599 | $149.95 | $159 | $159 | |
MODEM | Micro-connetion TI | PConnection Modem Card | Micro-connection A1A | Micro-connection A2A | Micro-connection TC1 | Micro-connection A1 | Micro-connection R1A | Micro-connection T1A | Micro-connection A2 | |
Manufacturer/Distributor | The Micro-Distributor Corp. | The Micro-peripheral Corp. | The Micro-peripheral Corp. | The Micro-peripheral Corp. | The Micro-peripheral Corp. | The Micro-peripheral Corp. | The Micro-peripheral Corp. | The Micro-peripheral Corp. | The Micro-peripheral Corp. | |
Compatibility | TRS-80 Modell | IBM-PC | Atari (with 850) | Atari (no 850) | TRS-80 Color | Atari (with 850) | RS-232 | TRS-80 II, III, 16 | Atari | |
Communication Standard | Bell 103 | Bell 103/113 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | |
Coupling Method | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | |
Baud Rate | 300 | 300 | 300 | 300 | 300 | 300 | 300 | 300 | 300 | |
Duplexing | full/half | full/half | full/half | full/half | full/half | full/half | full/half | full/half | full/half | |
Auto-Answer | no | yes | yes | no | no | no | yes | yes | no | |
Auto-Originate | no | yes | yes | yes | no | no | yes | yes | no | |
Self-Test | no | no | no | no | no | no | no | no | no | |
Carrier Detection Indicator | LED | onscreen | LED | LED | LED | LED | LED | LED | LED | |
Power Supply | AC | host computer | AC | AC | AC | AC | AC | AC | AC | |
Necessary Cables/Connectors Included? | yes | yes | yes | yes | yes | yes | yes | yes | yes | |
Terminal Software Included? | yes | yes | yes | yes | no | yes | no | yes | yes | |
Warranty | 90 days | 90 days | 90 days | 90 days | 90 days | 90 days | 90 days | 90 days | 90 days | |
Price | $209 | $170 | $239 | $279 | $199 50 | $199 | $199 | $259 | $249 | |
MODEM | Micro-connetion Auto-Print | Cat | D-Cat | Auto-Cat | 212 Auto-Cat | Apple-Cat II | 212 Apple-Cat II | J-Cat | 103 Smart-Cat | |
Manufacturer/Distributor | Micro-peripheral corp. | Novation, Inc. | Novation, Inc. | Novation, Inc. | Novation, Inc. | Novation, Inc. | Novation, Inc. | Novation, Inc. | Novation, Inc. | |
Compatibility | RS-232 | RS-232 | RS-232 | RS-232 | RS-232 | Apple II, II+, IIe | Apple II, II+, IIe | RS-232 | RS-232 | |
Communication Standard | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 & 212A | Bell 103 & 202 | Bell 103 & 212A | Bell 103 | Bell 103 | |
Coupling Method | direct-connect | acoustic | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct connect | |
Baud Rate | 300 | 0-300 | 0-300 | 0-300 | 0-300 & 1200 | 0-300 & 1200 | 0-300 & 1200 | 0-300 | 0-300 & 4110 | |
Duplexing | full/half | full/half | full/half | full/half | full/half | full/half | full/half | full | full | |
Auto-Answer | yes | no | no | yes | yes | yes | yea | yes | yes | |
Auto-Originate | yes | no | no | yes | yes | yes | yes | yes | yes | |
Self-Test | no | yes | yes | yes | yes | yes | yes | yes | yes | |
Carrier Detection Indicator | LED | LED | LED | LED | LED | light | light | LED | LED | |
Power Supply | host computer | AC | AC | AC | AC | host computer | host computer | AC | AC | |
Necessary Cables/ Connectors Included? | yes | yes | yes | yes | yes | yes | yes | yes | yes | |
Terminal Software Included? | yes | no | no | no | no | yes | yes | no | no | |
Warranty | 90 days | 1 year | 1 year | 1 year | 1 year | 1 year | 1 year | 1 year | 1 year | |
Price | $149.95 | $189 | $199 | $249 | $695 | $389 | $725 | $149 | $249 | |
MODEM | 103-212 Smart-Cat | Star Acoustic | P-113D | P-212 | VA103 Modemphone | VA315 | VA317 | VA355 | VA1252 G/K | |
Manufacturer/Distributor | Novation, Inc. | Prentice Corp. | Prentice Corp. | Prentice Corp. | Racal-vadic | |||||
Compatibility | RS-232 | RS-232 | RS-232 | RS-232 | RS-232 | RS-232 | RS-232 | RS-232 | RS-232 | |
Communication Standard | Bell 103 & 212A | Bell 103 | Bell 103 | Bell 103 & 212A | Bell 103/113 | Bell 103/113 | Bell 113B/113C | Bell 103/113 | Bell 202 | |
Coupling Method | direct-connect | acoustic | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | |
Baud Rate | 0-300 & 1200 | 0-300 | 0-300 | 0-300 & 1200 | 0-300 | 0-300 | 0-300 | 0-300 | 0-1200 | |
Duplexing | full | full/half | full/half | full/half | full | full | full | full | full/half | |
Auto-Answer | yes | no | yes | yes | yes | yes | yes | yes | no | |
Auto-Originate | yes | no | no | no | yes | no | no | no | no | |
Self-Test | yes | yes | yes | yes | no | yes | yes | yes | no | |
Carrier Detection Indicator | LED | LED | LED | light | lamp | LED | LED | LED | LED | LED |
Power Supply | AC | AC | AC | AC | AC | AC | AC | AC | AC | |
Necessary Cables/ Connectors Included? | yes | yes | yes | yes | yes | yes | yes | yes | yes | |
Terminal Software Included? | no | yes | yes | yes | no | no | no | no | no | |
Warranty | 1 year | 1 year | 1 year | 1 year | 1 year | 1 year | 1 year | 1 year | 1 year | |
Price | $595 | $199 | $260 (rack mounted) $395 (stand-alone) | $495 (rack mounted) $595 (stand-alone) | $250-$380 | $375 | $250 | $375 | $525 | |
MODEM | VA1250/55 | VA3413 | VA212PA | VA212LC | TNW-103 | Operator 103 | UDS-212LP | UDS-103JLP | UDS-103 O/A LP | |
Manufacturer/Distributor | Racal-Vadic | Racal-Vadic | Racal-Vadic | Racal-Vadic | TNW Corporation | TNW Corporation | Universal Data Systems | Universal Data Systems | Universal Data Systems | |
Compatibility | RS-232 | RS-232 | RS-232 | RS-232 | PET/CBM IEEE-488 | RS-232 | RS-232 | RS-232 | RS-232 | |
Communication Standard | Bell 202 | Bell 103 | Bell 103/212A | Bell 103/212A | Bell 103 | Bell 103 | Bell 212A | Bell 103 | Bell 103 | |
Coupling Method | direct-connect | acoustic | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | direct-connect | |
Baud Rate | 0-1200 | 0-300, 1200 | 0-300, 1200 | 0-300, 1200 | 300 | 0-300 | 1200 | 0-300 | 0-300 | |
Duplexing | half | full | full | full | full/half | full/half | full | full | full | |
Auto-Answer | yes | no | yes | yes | yes | yes | no | yes | no | |
Auto-Originate | no | no | yes | no | yes | yes | no | no | no | |
Self-Test | yes | yes | yes | yes | yes | yes | no | no | no | |
Carrier Detection Indicator | LED | LED | LED | LED | on screen | beep | none | none | none | |
Power Supply | AC | Internal | AC | AC | AC | AC | telephone line | telephone line | telephone line | |
Necessary Cables/Connectors Included? | yes | yes | yes | yes | yes | yes | yes | yes | yes | |
Terminal Software Included? | no | no | no | no | yes | no | no | no | no | |
Warranty | 1 year | 1 year | 1 year | 1 year | 1 year | 2 years | 1 year | 1 year | 1 year | |
Price | $425-$525 | $695 | $795 | $550 | $449 | $189 | $445 | $195 | $145 |