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!

 

How many volts do you require? How many LEDs? How about the blinking pattern?

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Microcontrollers are a good way to go.

 

If you are going to use self-timing (flashing) LEDs, then all you need is a battery, some current limiting resistors, and some wire.

Can you clarify what you consider an idiot box to actually be? Just a box with some blinking lights on it? Do they need to blink in any particular pattern, or randomly? What kind of brightness do you want? How long would you like it to last between battery changes/recharges? How large would you like it to be? How many LEDs per unit?


Torben

 

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Yeah this is the most suitable as he wants random blinking LEDs.

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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.

Right, on second thought I guess I'd hope if you were going to go to the trouble of putting an oscillator into a LED you'd include current limiting.


Torben

 

The LEDs with the built in flashing circuit, don't flash at the same frequency. I have a 5x5 matrix of them hooked up to the guts of a solar garden light, and its fairly random. Can upload a short video if you want. These were very cheap diffused reds, 100/$5.00, but pretty sure it would be tough to get a batch of these things made, where they are all precisely matched (seems like a lot of trouble and expense, for what they do). They flash at about 2 Hz, and I just wired them all in parallel, using 4.8 volts and no resistors (built into the LED, plus they flash (self limits heating). It's been going for over a year now, so its sound and stable.

Should give it a try with just a few on a breadboard, sort of how I stumbled on this.

 

Over 45 years ago I made some chasers with neon bulbs and 45V batteries. They chased for a while then the sequence got all mixed up then got back in sequence later.
I casted them into clear plastic. One exploded because I forgot to add a vent for the battery gasses.

Today I have many LED chaser circuits. Some use only two AA alkaline cells, chase around a few times, pause then chase again. The battery lasts for months because the LEDs blink for a very short amount of time.

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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.

 

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.

You noted that the circuitry would be different from your original boxes, which is true--with simple flashing LEDs the only circuitry needed would be the wire connecting the LEDs to the battery.


Torben

 

Yeah, this may be simpler than I thought--The main work will be finding supplies and the physical mounting of them.
Battery life is a consideration--my old ones would last at least a year. Don't know what it will be now--have to run them on a commonly available battery, like AA cells--I think I can fit them in the back of a Walnut board.

Findidng the LED's to use will be fun--one site I llked at had 15,047 of them to choose from!

I was heavily into electronics in the '60's, but have gone astray since then, as far as work went--dold fountain syrup, worked a plant electrician, drove an 18-wheeler,etc--whatever it took to make a living...

Retired now, need something to do... used to work on computers when they used big reels of tape, where we have HD's now....hehe.

 

I have had some experience with blinking LED's. By them selves they do not need a current limiting resistor as long as you don't exceed the specified operating voltage. Here is a data sheet on a typical one
http://www.us.kingbright.com/images/...EC/WP36BHD.pdf
This one is a blinking LED the can be purchased from Mouser electronics.
www.mouser.com. The LED part number is WP36BHD.
I have also put other LED's in series with the blinking LED's and those in the string all blink at the same rate. I have also put them in parallel on the same battery. There is some interaction if the blinking LED are physically to close to each other.
The thumbnail schematic is of a circuit that I built that sinmulates a flickering candle. When initially powered the two blinking led's are in sync, but as time goes they get out of sync and the single orange LED appears to flicker like a candle. The circuit was built and put in small plastic pumpkins for halloween.
I found by putting black heatshrink tubing over the blinking LED's they did not interact with each other so much.

Attached Images

candle.JPG (4.5 KB, 9 views)

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