The Tchotchke - John Dunn, Consultant, Ambertec, P.E., P.C.

Maybe this URL will be off-line by the time you read this, but if not, it's worth a look. It shows what is supposed to be the world's most useless machine.

http://gadgetbox.msnbc.msn.com/_news/2011/05/12/6624781-the-worlds-most-useless-machine-version-20?gt1=43001

It reminds me of a Candid Camera program of many years ago where Alan Funt showed a useless machine. It was a Bud box with nine NE-2 neon lamps mounted in rubber grommets with each lamp blinking on and off at its own individual rate in what was obviously a collection of relaxation oscillators.

You remember this thing, right? A ninety volt battery, a 0.1 µF capacitor in parallel with the NE-2 and a multi-megohm resistor feeding them.

 

Alan Funt and Durwood Kirby explained to viewers that this box was utterly and absolutely useless, that it served no purpose of any kind so they took it out to the street and asked passersby what it might be good for.

The big joke was that as useless as this thing was, people tried very hard to envision a purpose for it and that was the big joke. (Ha ha ha.) Let's laugh at all these stilly people with their silly ideas.

What nobody came up with was the possibility that this thing might serve as a children's night light, a blinky little friend sitting on a night table near the crib or bed. I don't know for sure, but just maybe this thing wasn't really the useless tchotchke it was cracked up to be.

Seen any useless things lately?

Comments

[Cor van de Water]

I actually built this neon blinker, worked pretty well and you can even test the quality of neon lamps with it. If a lamp is bad it will still light but not blink

[Jerry Meyerhoff]

I too built such a blinker as a young technologist & was facinated that a combination of "passive" 2 terminal devices could create a dynamic action. The saw-tooth signal was usable as a crude signal generator using various R & C values. It was also good to detect leaky or open capacitors. The 2 bulb multivibrator version worked in a toy making alternate blinking eyes. JDM LABS

[John Dunn]

Hi, Jerry.

The neon lamp has a breakdown characteristic that goes through a step when the gas ionizes. Gas villed voltage regulator tubes, OA2 and the like, also have that trait and can go into relaxation oscillations if paralleled with a capacitor.

Even some early zener diodes would do this same thing although what the part numbers of thse early devices were has long since escaped me.