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A (Birth)Day In The Chances are, these days, one of the first things you do when you arrive at work is use a computer. Ever wondered just how that computer came into being? By ROSS PHILLIPS To the general public, even in 1989, computers are rather formidable devices. To those with a technical "bent", they're rather less frightening but most of us still think of a computer as a "black box". SILICON CHIP has a large proportion of readers whose interest goes more than skin deep. So we thought you'd like to go behind the scenes and visit a computer manufacturer. As well as the several locally manufactured computers, there are literally hundreds of brands being made around the world. Most come from Asia: Taiwan and Korea, Hong Kong, Japan, even China. And most have similar methods of production, with various degrees of automation. Singapore, also, has a thriving computer industry - and when the opportunity arose for someone from SILICON CHIP to visit Singapore's leading computer manufacturer, we naturally said yes. The company, Essex Electric, makes a range of IBM compatible computers under the "IPC" brand (the letters standing for Intelligent Personal Computer). A small proportion of their production is for the Singapore market but the vast majority - over 1000 per week are destined for distributors throughout Europe, Asia, Australia and New Zealand. The first thing that struck us about the Essex Electric manufacturing facility, located approximately half way between the business centre of Singapore and Changi (of War Prison and later in- ternational airport fame), is the lack of salubrious surroundings. However, we soon learned that this was typical of Singapore; apart from the fact that every square centimetre of land is precious (meaning factories are high rise for the most part), the tropical climate makes painting the buildings a waste of time and money. No robots Another surprise was the lack of automation. No robot assembly lines here: IPC computers are made almost entirely by hand apart from flow soldering of the PCBs. However, labour in Singapore is relatively cheap compared to, say, Australia: the average worker in a factory earns around S$1000 to S$1200 per month (A$700 to A$800). Hence labour intensive industries can succeed where they would not elsewhere. But we're jumping ahead of the story. Let's go back to the start. Essex was formed in 1980 by two brothers who graduated in electronic engineering from the University of Essex (UK). Initially set up as a specialist printed circuit board manufacturer, it now concentrates entirely on the making of computers and related products. In fact, the original PCB manufacturing facility was sold off in 1984 - and Essex has remained its largest customer. The philosophy has always been "quality first" . The company made a decision very early in its life not to cut corners to save money. Research and development READY FOR ASSEMBLY: a blank PC board is placed on a conveyor belt so that the sockets and passive components can be fitted. The boards are pre-baked in an oven to force out every last smidgin of water. 6 SILICON CHIP This attention to quality becomes obvious in the research and development department. No pressure is applied to the team of engineers to produce faster - even if it takes a little longer, management knows that the designs coming from R&D will be optimum. While we were there, a team of engineers was working on the next Life Of A Computer in microns, not millimetres! When completed, a copy of the CAD software is sent off to the PCB manufacturer, who has the ultraprecision plotters necessary to convert it to film. Completed boards are delivered back to the factory hermetically sealed and each one is visually inspected for flaws. PCB assembly AFTER THE PASSIVE components have been fitted, all the ICs (with the exception of the RAM chips) are installed. The earth strap fitted to the worker's wrist protects the ICs from static electricity. Essex product, a point-of-sale (POS) terminal suitable for everything from the smallest motel or service station through to the largest retail chain. The enthusiasm of the design team was infectious: before we left the laboratory, we were firmly convinced that the Essex POS terminal will be the greatest thing since sliced bread! Many prototypes are made of each design. Every one is subjected to " worst case" analysis to allow for component tolerances well in excess of what could be expected. Many are tested to destruction. PCBs are designed, tested and retested. Layout is done with the aid of a $300,000 CAD system, and in some cases extends to a 6-layer board. Track widths are measured Immediately before assembly, each board is baked in an oven to force out every last smidgen of water - particularly from the component holes. This simple step virtually eliminates dry joints when the boards are later soldered. The boards are assembled in two stages on one production line. First of all, the sockets and many of the passive components are inserted, then the active components, crystals, etc are inserted, all by hand. Components purchased for use in the Essex plant are top quality, prime spec devices. Even then, all batches are randomly sampled by quality control. If any devices are not to spec, the whole batch is rejected. It is perhaps fortunate that the modern computer board uses so ABOVE: WHEN DRY, the boards enter an automatic testing station before passing to the next stage of assembly. LEFT: AFTER FLOW flow soldering, the still hot board is dunked in a bath of pure water! JULY 1989 7 FOLLOWING THE AUTOMATIC testing station, each board is powered up and run for a full 24 hours in an enclosed cupboard. The heat build-up inside the cupboard further stresses the components and shows up any faulty boards. few components: a completed board emerges from the assembly line every few minutes. Once the board has reached the stage where static damage-prone devices are involved, all workers on the line are earthed to both the board and a common earth via wrist straps. Immediately before the flowsoldering machine is a quality control officer, who visually inspects all boards and pushes down all ICs, sockets, etc to ensure they are fully "home". We weren't quite ready for the next stage of production: as each board leaves the flow-soldering machine, while it is still hot, it drops into a bath of pure water. That's right, each board is immersed in water - for a period of about five minutes! The quality control manager explained that this is one of their most important tests. Because the board is still hot, the cold water causes a mild shock to every component and solder joint. As any serviceman will tell you, it's those dry joints which get you: often years later. The shock of the cold water bath shows any suspect joints immediately - no waiting! But that's not all: each board is then thoroughly washed in a hot water spray. This removes any flux or solder residue and again places the board and its components under high stress. The pre-baking and the water bath between them have virtually eliminated dry joints in this factory. Assuming the board has passed this stage, it is then dried off with compressed air, then thoroughly baked for several hours to completely dry it out. After drying, the boards are placed on another chain conveyor where component _pigtails etc are removed by a high speed rotary saw. Finally, each board is given close visual inspection by another quality control officer before being passed through to dynamic checking. More quality control Each board then enters a 100% component and operation check in a fully automatic testing station. The PCB is placed in a jig, and is brought into contact with many hundreds of "fingers". Under computer control, every facet of operation is checked in just a few moments. The readout on the computer screen is simple: "good" - everything passes, or "bad" - a ABOVE: AFTER FINAL assembly, the computer, together with its monitor and keyboard, is checked for a full 48 hours in the "burn-in" room. LEFT: A TECHNICIAN examines a reject board from the automatic testing station. If a faulty component is the cause, it is replaced on the spot and the board re-enters the test procedure. 8 SILICON CHIP single failed test procedure means rejection. In fact, the computer testing procedure will print out a report indicating to the technicians which component or area of operation is faulty, making the subsequent repair simple. If a PCB is repaired, it re-enters the testing procedure as if it had just come from assembly. 24-hour burn-in Each PCB is then powered up and run for a full 24 hours in a specially designed cupboard containing perhaps 20 or 30 other boards and power supplies. Because the cupboards are fully enclosed and insulated, the heat build-up is high - subjecting the components to further stress; far more than they would be expected to undergo in normal life. Final assembly If the PCB gets the nod from quality control, it is then stored in a controlled atmosphere ready for final computer assembly. As the computer is assembled, the memory, disk drives, display cards, etc, as specified by the customer, are fitted. The "customer" is not the distributor: he or she is actually the end-user customer. For example, a customer in Australia might order a "NEAT (286) type with 4Mb memory, 40MB 28ms hard disk, 1.2MB 5¼in and 1.44MB 3½in floppy drives, and VGA graphics, in a desktop tower case". The local distributors, CompuHelp Australia, would fax this order direct to Essex in Singapore, and a work sheet would be prepared immediately listing that configuration. Each component necessary to build the computer to those specifications would be taken from the store, and routed through to the final assembly area. Around 20 technicians are involved in assembly and each one can complete a computer in around half an hour. So, depending on the hours worked, the factory has a production capacity of between 250 and 300 hand-built computers per day. THE FINISHED PRODUCT: this particular machine uses the new enhanced AT chipset and runs at 20.5MHz in turbo mode. It is equipped with a 5¼-inch 1.2MB floppy disc drive and a 40MB hard disc. When completed, the technician will power up the machine and test basic operation. He will then format the hard disk, load DOS [the disk operating system) and ensure the computer is fully operational. When the technician is satisfied with his handicraft, he despatches it to the final stage of production, the 48 hour burn-in room. Here, every computer is "married" to its appropriate video monitor and keyboard, and all are checked for a full 48 hours with a series of diagnostics and routines that cycle through every component. Only if the computer system passes through every check with 100% success is it considered now finished. Each of the quality control check-lists stays with its computer until delivery to ensure nothing is left to chance. Despatch While the computer might be electronically finished, it still has to be prepared for the rigours of transport. Specially designed foam [not styrene) packaging holds the computer firmly and securely within its transportation box, which also contains the keyboard and manuals. The monitor is packed separately. Normally, computers are despatched by air, meaning the customer doesn't have to wait any longer than necessary for his or her machine. ~ JULY 1989 9