Blowing (letting) some smoke (out)
Clarke explains why some still believe electronic devices run on electricity rather than smoke…
There seems to be some occasional confusion about the term “letting the smoke out” of electrical or electronic devices. I thought it might be informative, and hopefully enjoyable, to some if I explain the term and its origins.
Back in the 1970s, there was a humorous explanation for the failure of certain electronic devices because the failure tended to be accompanied by emission of usually very foul smelling smoke. This was especially true of transistors encased in an epoxy housing. When overheated, a very small transistor that could easily fit inside a 1/8-inch cube could emit an unbelievable amount of smoke. I recall clearly when I worked on a digital-voltmeter production line as a technician at Hewlett-Packard (in 1970, a couple of years before I was officially offered a position as a full-blown engineer) and one of the instruments I was testing blew a small plastic-case transistor. It produced an unbelievable amount of smoke and stench, yet, when I removed the power and started looking for the offending component, all looked “normal”. It was only after very close scrutiny that I was able to discern a very minute (as in almost invisibly small) crack in the flat face of one Motorola transistor where the smoke had escaped.
In clear demonstration that my experience was not unique, there was an article, some months or perhaps a few years later, in an electronic journal, proposing the thesis that all electronic devices ran on “smoke”, and the notion that they actually used electricity was a fraud being perpetrated by antiquated old-timers who were a bit out of touch with the new-found reality. Offered as proof was that as long as the smoke circulated unimpeded through the invisible innards of said electronic devices and systems, all was well, but if a leak developed at any point in the system that allowed the smoke to escape, there was always a system break-down inevitably traceable to a component failure not far from where the offending smoke had been detected.
From an empirical viewpoint, as perceived by the casual observer, this obviously makes sense, particularly when nobody had ever seen an electron, and therefore there was serious doubt as to the actual existence of the same. Hence, the much more plausible explanation of smoke being the means by which such devices functioned thus caught hold, and continues to this day. For those “savvy” to the trade, it’s obviously great tongue-in-cheek fun, but for someone lacking the historical perspective of the legend, it can be somewhat baffling if adequate explanation is lacking.
So the real reason for the “smoke” theory? When you work all day with a bunch of intellectual geeks and nerds, somebody has to come up with something obtusely non-serious to rattle the apple cart and restore some degree of sanity to the environment.
Clarke
