I think most young engineers go through a few rites of passage on their way to developing into full fledged engineers. These times are when their latent possession of “The Knack” is revealed, and an observer can gain a glimpse of their trajectory into the future. For electrical engineers, some of these rites are draining countless lantern batteries by connecting then up to coils of wire wrapped around nails, taking apart an electric motor and putting it back together, and seeing that it still works, and of course, experiments with mains power.
My mains experiment involved connecting a 9v transistor radio to the mains by way of a power cord that I clipped from some other item, stripped, and wrapped the wires around the 9v battery terminals. It produced some smoke but that was about it. It could have been worse, a friend set his bedspread on fire trying to recharge D cells with mains power.
Today my eldest son completed his first electrical gadget built from scratch. It was the ever popular telegraph (said item is photographed above), made from a couple scraps of 2×4, strips of sheet metal, and enameled wire wrapped around nails. He is in the middle of a physics block in his 6th grade class, which he is really enjoying, and decided to build “something electrical” for his spring report. He’s still got some loose connections to clean up but it works and he couldn’t be prouder.
Speaking of telegraphs, some time ago I ran across an article about the early history of the telegraph industry over on mises.org, and the parallels between it and the development of the internet in the last decade. There are surprising similarities, including the wild scramble for development capital, the changes that “instant” (in 19th century terms) transmittal of information brought to society, and the fly-by-night enterprises that sprung up and later either failed or were merged into the final dominant company, Western Union. It was an interesting read and I would recommend following the link to read it yourself.
Alexander’s younger brother has heard of crystal radios and has been bugging me to get him a kit so he can build one, so watch for that project in a future column.
EDN Gadget Freak