If you are going to use self-timing (flashing) LEDs, then all you need is a battery, some current limiting resistors, and some wire.errol7 said:In the '60's I made what I called "idiot boxes" -- These were just NE2's with an RC curcuit to make them blink, and two 45-volt batteries in series.
I want to make a modern version of them, with self-timing LED's, and a lower-voltage battery.
Any ideas would be helpful!
Do they all contain current-limiting resistors? I've never played with them. I have some blinking neon lamps though. They're very pretty. Also no resistors needed.blueroomelectronics said:
I have some flashing 12V lamps from the Source (what used to be Radio Shack, here in Canada). I think I have red, green, and blue ones. They use more juice than LEDs but they're also quite bright and I think they're very pretty. Just by themselves they have a fairly regular flash rate, but a bunch of them running at the same time do get out of sync. For even more randomness I stuck them on a simple oscillator. I was running the whole thing off a bench supply (I was just fooling around late at night when I did this) but a wall-wart would have worked just fine. I don't think a battery would have lasted very long though. At least, not as long as flashing LEDs would.errol7 said:Thanks for the replies, guys!
I know I didn't describe the idea very well--that's because it's just an idea, so far. I made the 1966 versions in many forms, mostly in a routed-out Walnut board that would hang on the wall like a picture. I used
NE-2's, AR-2's, and ZE-2's (Zenon) for various colors.
Now, obviously LED's would be the choice, but the circuitry will be different, as the gas discharge lamps were part of the circuit.
They were purely decorative--just a random blinking patern, but they had a definite appeal. I can still get NE-2's, but they don't make the 45-volt batteries nymore.
I can use a simple half-wave rectifier on the house current for the supply, but then you have a cord to deal with.
Thanks for the info clsgis. I just wanted to point out that this thread is from 2008....I built a couple of NE-2 idiot boxes decades ago, and one recently. The first one used a type V60 90-volt B battery. Those were used in portable tube radios. Since then I've used ten 9-volt alkalines in series.
When I first came across the circuit, it was called a "Yale Idiot Box" but I never got any more history than that. Anybody know where the circuit came from?
Part of its charm was there were no wires or controls or fasteners visible on the box, and it runs for years on one battery change. So the current draw must be very low. If I had to use LEDs, I might use an LMC555 or ICM7555 for the oscillator. More tunable and perhaps less current than a self-blinking LED. But I'm afraid no single LED makes as complex and subtle a display as a partly-struck neon glow lamp. Also, the three-bulb neon Idiot Box changes direction occasionally, and responds to sunlight because neon plasma is slightly photosensitive. It would take quite a bit of logic to simulate that with LEDs.