The Trials of Picking a System

By Peter J. Schuyten
The New York Times

June 24, 1980

The first thing to know about personal computers is how hard it is to buy one. Even if you have been directed to a popular computer store, as I was to the Datel outlet in Rockefeller Center, the decision as to which model to buy, of the literally scores on the market today, can be as perplexing a buying a new car - and sometimes as expensive.

While ultimately, of course, these things come down to a matter of personal preference - what suits your needs and conforms to your budget -you will want to know what the different manufacturers' systems cost, their capabilities and, more importantly, whether the investment in time and money will be well spent.

Unfortunately, as anyone who has ever bought a computer knows, the computer salesman is often little help. Typically, the people who sell these machines fall into two categories: those who know the product but seem more interested in showing their command of the field than in making a sale, and those who seem to know little or nothing at all about computers.

The fact is that computer stores can be unnervingly like many stereo speciality shops. If you do not speak the language, you cannot buy the product. Even experienced computer users complain about the confusing stream of buzz words, or ''computerese,'' that passes for information at many of these outlets.

''There is no hard sell,'' one industry supplier laments. ''In fact, there is almost no sell at all. It's a market that thinks it can work entirely on intellectual curiosity.''

To avoid being totally vanquished the first time you cross the threshold of your local computer store, it is advisable to arm yourself with the basics of computer terminology, beginning with the difference between hardware and software.

Hardware does not refer to nails, augers and saws, but to the physical equipment that makes up a computer system, the central processing unit, or C.P.U., for example, memory devices and the like.

Programs for Everything

Software, on the other hand, is the programmed instruction that tells a computer what to do - in effect, the tool that turns your computer into a useful appliance, allowing you to communicate with it in English. There are programs for everything, from vector analysis to polishing your backgammon skills, and they are contained on audio tape cassettes, plug-in cartridges or record-like plastic disks, called ''floppies.''

To begin computing, you will need what is know as ''a minimum starter set'' - a central processor, a typewriter keyboard for communicating with the computer, and a television display screen that allows the computer to communicate in return.

In addition, you will need an external memory device of some kind, either a cassette recorder or floppy-disk drive to play, or ''load,'' the software programs into the computer's memory. The programs range in price from $5 for a simple video game to $150 for a sophisticated business analysis application.

A word of explanation about memory. It comes in two forms, the internal memory circuits that reside within the computer, allowing it to retain information while in use, and external memory in the form of tape cassettes and floppy disks. These not only contain programming but are also used for permanent storage of information generated by the computer.

From $500 to $10,000

Personal computers are available in three price ranges: $500 systems that are the next step up from television-based video games; systems that sell for around $1,200 to $1,500, and, for the truly serious user, units that begin at around $3,500 and run up to $10,000 or more.

These prices represent nothing more than your initial cost. Once hooked, you may find yourself doubling and even tripling your initial investment as you increase the sophistication of your system.

''These machines can nickel and dime you to death,'' said one retailer in a moment of candor. Cassette recorders, for example, can be purchased for as little as $30, whereas the box-like disk drive units start at around $500, but are far more convenient to use.

Similarly, most personal computer owners find it useful to make a physical copy of what is on the display screen. For that you will need an optional printer, costing anywhere from $250 for one that prints on an adding-machine-like tape to $3,000 for letter-quality copies.

The Computer and Your Television

And for those wanting to retrieve information, say up-to-the-minute stock market quotations or United Press International news reports from a data bank, a telephone modem will cost around $200.

Some brands, notably Radio Shack's TRS 80 and Commodore International's Pet model, offer a central processor, keyboard and display screen combined into a single unit. Others, the Apple II for example, come with only a keyboard and plug-in jacks at the back. In this case, it will be necessary to purchase separately either a television monitor, or, if you do not mind tying up the family TV set, an interface device, known as an R.F. - or radio frequency - modulator, that permits you to use your computer with your home set.

While an RF modulator costs only $40, monitors that have none of the signal decoding circuitry found in a television receiver are said to offer a sharper picture. Some users therefore recommend spending the extra $200 or more that a monitor costs.

In buying a computer, you will find yourself making many of the same kinds of price and performance decisions that businessmen make when selecting a professional data processing system. The most important of these is the amount of internal memory, in the form of plug-in random access circuit chips.

16,000-Character Memory

Starter sets come equipped with up to 16,000 characters, or ''16k bytes'' of memory already on board. You can, however, with the addition of plug-in circuit chips increase the internal storage capacity of your machine to 48,000 characters or more, and many users say it is money well spent.

''You always seem to run out of memory no matter how much you have,'' said one. Then, too, some systems perform in color - not essential, but fun for graphics and video games - while others come only with black and white.

More important, perhaps, most computers in a given price range offer essentially the same hardware performance, and are differentiated, instead, by the amount of software that can be used with them.

Almost in the same way, say, that a videodisk machine is limited by the amount of entertainment that is available to be played on it, a computer's utility is directly related to the software that has been created for it.

A Question of Sophistication

Unless you are prepared to invest literally hundreds of hours in learning how to ''write'' your own programs, you should investigate what the kind of software is available for the model you are choosing.

Keep in mind that the degree of sophistication of your computer system is virtually always a function of how much it costs. The $500 computer, to many users, is little more than an ingenious toy, good for playing video games, occupying the kids with educational exercises and performing the most rudimentary applications in the home, say, balancing a checkbook, storing telephone numbers and other projects that quickly take on a make-work character.

The chief argument in its favor is that it keeps your investment to a minimum, while allowing you to explore, on a elementary level, the mysteries of computing. Then, later on, as your interest grows, you can increase the sophistication of most of these systems by purchasing additional hardware.

On the other hand, if you are serious about computing, you may quickly become bored with these less expensive machines, and might be better off starting immediately at the next tier.

For my part, I thought I'd try an $1,190 Apple II, with the minimum 16k of memory, a cassette recorder, and an RF modulator to hook it into my six-year-old color television set.

GRAPHIC: Illustrations: chart of a basic home computer system