BUYING a Timex Sinclair machine can be the start of a lifetime obsession with home computing. It is easy, however, to become discouraged if everything does not go according to plan from the beginning.
For those with only a little knowledge of computers and their capabilities, the best way to approach the machine is to abandon any ideas for special uses. It is better to become familiar with the many facilities and then decide how you wish to use them.
Begin by unpacking your machine, overcoming your surprise at its size and weight and, following the manual to set up the system. If you cannot get the K on the screen, check that everything is plugged into its correct socket and reset the machine by pulling out the power plug for one second and plugging it in again. If still nothing appears, check the power supply unit by shaking it. If it rattles, return it. If it is okay, check your system with that of a friend.
Once the K appears you are ready to begin learning about your machine. It can prevent family arguments if you can afford a separate television set for your system. It also makes life easier if you find somewhere to leave your equipment set up permanently. You will find that a few power sockets are needed and a four-way block connector on a short length of extension cable will help to make it tidy.
The manual is written in great detail and is reasonably easy to follow. Some of the chapters may not seem immediately relevant but it is worthwhile reading them as you might miss something important.
At this stage, patience is needed in learning the ways in which the computer will accept information. It is tempting to try to enter programs before you are ready but that is likely to lead to errors. For example, words like AND, THEN and AT should not be typed in letter by letter.
By the time you have reached chapter eleven in the T/S1000,ZX81 manual, you should have accumulated sufficient knowledge to be able to type in other people’s programs, such as those in Timex Sinclair User.
It is important when using the T/S1000,ZX81 that it is not jolted. Some of the connections can easily work loose and everything which has been entered will be lost.
As a way of relaxing you can buy some of the growing range of commercially-produced software. This can be loaded directly from cassette but make sure that your machine is big enough to take the tapes you buy.
The tapes vary in quality, and it is advisable to read the reviews in Timex Sinclair User and use your judgment to find the best.
An alternative method to learn about the T/S1000,ZX81 is to plunge in at the deep end and see what the machine will do. Refer to the manual when you have difficulties. You can ignore the functions and calculations initially and experiment with PRINT statements to obtain the feel of the machine.
You may already have heard about the problem involved in SAVEing and LOADing your own cassettes.
Usually they occur when LOADing tapes recorded by other people. One simple method to overcome this is to wind the tape to the middle of the program and type LOAD”” followed by ENTER; then increase the volume of the recorder slowly with the tape running until the television screen shows four or five thick black bands. If you then rewind the tape, the program should LOAD normally.
Finally, a health warning. Apart from any practical uses, computing with your Timex Sinclair machine can be a very entertaining hobby and is almost certainly habit-forming. You may easily find yourself crouched over your machine, red-eyed, in the early hours of the morning thinking that in another five minutes you will solve the problem. Try to break that habit by getting into the fresh air and meeting other Sinclair users.
By obtaining a Timex Sinclair computer you find that you have joined a not very exclusive club with many thousands of members, many of whom would be only too happy to advise you if you have difficulties.
Make sure of your regular copies of Timex Sinclair User and you can be guaranteed many happy hours.
GLOSSARY
Basic — Beginners’ All-purpose Symbolic Instruction Code. A programming language resembling English which is used by beginners because most popular microcomputers have it as standard.
Bug — an error in a program.
EPROM — Erasable Programmable Read-Only Memory. Semi-permanent storage. Information is not erased if the power is turned off in the computer. Programs can be erased by subjecting the memory chips to ultra-violet light. The memory can then be reprogrammed using an electrical device called an EPROM blower.
Interface — RS232 and Centronics. A device which enables other computers or add-ons, such as printers, to be connected to the computer. It converts non-standard signals from add-ons to the standard signals of the computer in use.
Kilobyte (K) — A measurement of memory size. Most machines use 16K as a minimum but 48K is generally agreed to be necessary for serious work.
Machine code — An electronic pulse code used by the computer to perform functions and communicate with memory and other devices.
Mnemonics — Abbreviated instructions — e.g. LD for Load — used in machine language programming.
Motherboard — An external printed circuit board which is used like a multi-way plug planner. It enables other printed circuit boards, such as graphics boards and color boards, to be slotted in.
Port — A link to the outside world which can be used by programs and the computer.
PCB — Printed Circuit Board. A board which has on it the electronic circuits of the computer.
RAM — Random Access Memory. Information and programs can be stored in this type of memory as electronic pulses which conform to a set of numbers — machine language — in which programs are represented in the computer. When the power is turned off the information will be lost.
ROM — Read Only Memory. Information stored in this type of memory is not lost when the power is switched off.
Software — Programs which control the operation of the computer.
Syntax error — a bug caused by incorrect use of a programming language.