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help needed

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New Member
Hi All,
I was wanting to create a light box that my dad built for me when I was about 5. It had som small lights in it that was connected to a couple of 9 volt batteries. All it did was blink in a random pattern. It did this for at least 20 years before all of the lights went out. I was telling my son about this and he thought it was cool. Could some one help me with the parts needed and how everything will need to be connected sot hat maybe I can build one for my son.
He said he thought that if there was 3 rows of six lights with the top and bottem blinking going one way and then the middle row blinking going the other was would be cool.

Can some one help me with this. I would greatly appreciate it.



New Member
I think he meant that the box worked for 20 years, but not on the same batteries...

I'm guessing it used bulbs that eventually burned out. If you still have it, open it up and see what lurks within.

It could have been as simple as using 9V Christmas bulbs (or something close to that voltage, unless they were wired in series), and using blinker bulbs to make them flash.

You can get LEDs with flasher chips built in. They don't all flash at exactly the same rate, so if you wire up a bunch of them you can get a random flashing pattern. Or you can use 555 timers, or logic gates, or even a microcontroller.


New Member
I don't have the box any more, so I not sure what was in it. When specifying the battery I should have said a 90v that he got whiile working for the phone company.


Super Moderator
I made one a long time ago, I could not find the exact circuit but this one is close, and you dont need a 90v battery.



Well-Known Member
Most Helpful Member
When I was a kid I made a chaser with neon bulbs and a 90V battery then cast it in clear plastic. It worked for a few months then it blew up because it had no vent for the battery gasses to escape.


New Member
flasher circuit

I couldn't afford the 90 volt battery, but the hardware store down the road had 9Vs on sale for about 10 cents so I clipped them together in series and made my neon relaxation oscillator, it work for some time. My first electronic circuit that worked. Oh, them days!:)
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