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Idiot box

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errol7

New Member
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!
 

Torben

Well-Known Member
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!
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
 

Torben

Well-Known Member
blueroomelectronics said:
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
 

HarveyH42

Banned
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.
 

audioguru

Well-Known Member
Most Helpful Member
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.
 

errol7

New Member
Idiot Box --- replies

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.
 

Torben

Well-Known Member
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.
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
 

errol7

New Member
Idiot Box --- replies

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.
 

k7elp60

Active Member
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.electro-tech-online.com/custompdfs/2008/04/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.
 

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clsgis

New Member
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.
 

DerStrom8

Super Moderator
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.
Thanks for the info clsgis. I just wanted to point out that this thread is from 2008.... :D
 

duffy

Well-Known Member
Unfortunately, you can't really simulate the old neon idiot box that same way with LEDs because the neon had a built-in hysteresis effect: the voltage had to go up to about 60V or so to arc over, then it would conduct down to 30V or less. So you could make them blink with just a capacitor and a resistor or two.

The led, of course, simply starts conducting at a certain voltage and shuts off below it. Putting a cap across it would just make a filter, not a relaxation oscillator.

But then again - you can charlieplex a hundred LEDs just using a crappy $1 microcontroller and a dozen resistors.
 

clsgis

New Member
Just for the hell of it, I rigged up two nine-volt batteries on a CMOS commutator, driving an six stage Villard cascade. The voltage multiplier is 50% efficient until the cascade charges, and then the main loss is the diode drops. Generates 100 volts and runs the neon oscillators just fine. The commutator takes three 4000B-family jelly beans and an H-bridge made from four discrete mosfets. I can draw a schematic if you're interested.
 

duffy

Well-Known Member
^ Beats trying to find a "B" battery.
 
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