Crystal AM Radio
(During the Second World War, Prisoners of War used a razor blade and a pencil lead in place of the crystal to make secret radios.)
Along with the demise of the incandescent light bulb (as mentioned yesterday) there have been other fundamental changes in technology. A century ago a radio receiver could be assembled by virtually anyone using items such as a galena crystal, and some wire wrapped around a toilet paper (or similar) tube. The only component you really needed to purchase was a set of headphones.
A transmitter required a bit more – an ignition coil from a car, a tuning coil wrapped around an oatmeal box. The telegraph key was the main purchase item. Incidentally, the construction was called “breadboarding” since the parts were mounted on a piece of wood, such as the board used to cut bread.
Fifty years ago you could tune your car with a set of basic tools usually twice a year. Oil and filter, set of sparkplugs and ignition points, and every so often a new set of sparkplug wires.
Today most people don’t work on their own cars; they take it to a shop where (for $79) the mechanic hooks a device to the car’s computer and the computer reports what the car needs. If that clunking noise isn’t something that the computer tracks, it must not be important.
Electronics – the same way. As a kid if the television wasn’t working right, I’d take the tubes out, ride my bicycle to the Rexall Drugstore, use their tube tester and purchase a replacement tube right there.
Today’s devices aren’t home-repair or experimenter friendly. First, the manufacturers glue everything shut; second, there’s very little in the way of documentation.
I guess I’d like to point to today’s kids and complain that they spend all their time playing video games and texting, but can’t. If there’s no 21st century equivalent of a mechanical alarm clock begging to be taken apart, just to see how it works, how can we get them excited? Kids are still naturally curious – now we have to figure out how to feed their curiosity.
sfnowak 