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<p class="MsoNormal">I was a reader of AR73 about then and read many of Wayne Green’s editorials. He overemphasized the future market for microprocessor based device design. They weren’t talking yet about problems with enclosure cooling much.<o:p></o:p></p>
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<p class="MsoNormal">What was obvious back then was that word processing would be the real strength of the personal computer.<o:p></o:p></p>
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<p class="MsoNormal"><b>[ </b><a href="mailto:deanvp@att.net">deanvp@att.net</a>] I’ll mention a completely tangential electronics cooling issue that probably most of you never heard about. I’m going to go back to when God was a kid and the Mitts “Altair”
8800 Computer was first coming out as full working computers or they were sold as a kit that a hobbyist could assemble. I don’t remember the exact year right now but both Microsoft and Mitts were still in Albuquerque, NM. 1975 or so. Later Pertec aquired
Mitts and started selling business systems using the basic Mitts computer. All packaged up as a nice system for small business owners. Mitts didn’t know how to market or how to manage a fast growing business so they sold to Pertec who had no idea how to deal
with a “micro-computer based business system. They were a disk drive manufacturer. Pertec started offering their systems and customers were having all kinds of weird results on their accounting software. Turned out the cooling of the standalone computer case
was adequate but when in a system enclosure the system occasionally was running too hot causing all kinds of weird results. The real cause of the problem was how the ribbon cables were routed inside the computer case. Properly routed everything work fine
even in the system enclosure. The case by itself wasn’t that sensitive in an open standalone environment. How’s that for going back to when Microsoft only had 9 employees? Does the name Imsai ring a bell?<o:p></o:p></p>
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<p class="MsoNormal">[<b> </b>James Peck] They may have given up on trying to keep electrical cabinets cool by natural means. A couple of years ago I encountered a US built mechanical servo press that had a chiller mounted up on a top platform and water/air
heat exchangers inside the electrical enclosures. The temperature switches would shut the press down if the temperatures inside the electrical cabinets rose into the upper nineties. The fan motors on the heat exchangers would get some dirt from air in their
bearings and bind up. The cabinet would overheat and the temperature switch would shut the press down with a fault.<o:p></o:p></p>
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