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pretty lights

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fazer

New Member
hi all , i am starting a small project and would like some help as i am just a newb.

i want to make a chain of lights (led's,or small neon's)probebley 30 lights long and i would like them to flash in seqence the neons i want to use are 1.5 v
 

thec

New Member
Hi.

Since it was like 7-8 years I did this I really can't remember how it all worked, but I used a IC called "4017" from some company, which did the exact thing you wanted. Except that if you want 30 lights you'll need to hook up several of them (3-4 I guess) in serial.. but that's really not any problems.

Watch out for static electricity as 4017 are really, really, sensitivt. Some kind of IC "holder" (sorry, don't have the words) which you solder and at last put your IC in would help a lot.. it's a great tool for sensitive IC's ;-)

Here is a techfile in english from a swedish distrubitor (ELFA AB):
http://www.elfa.se/pdf/73/735/07354996.pdf

And since the 4017 has a minimum main at +5V (think it can take up to 12V actually) hosting 1.5V neons are no problem, you'll just need to calculate your resistors in serial with the neons from output to ground right. No, don't ask me :) I would _GUESS_ 470ohm would do it at +5V current, but if someone would show me an exact number and how it was calculated, noone would be happier than me :)

Good luck!
//Albert "thec" Sandberg
(no, "thec" is not at all like "tech", it just sounds like it, hehe)
 

tom_pay

Member
What about rather than using multiple 4017's why not have one of 10 outputs drive 3 LED's therefore you have 3 different chains all chasing each other.

Is it for a storefront?
 

audioguru

Well-Known Member
Most Helpful Member
This thread is almost 7 years old.
A neon light bulb needs 65V not 1.5V.
The output current of a 4017 with a supply as low as 5V is almost nothing (about 4mA into an LED without a current-limiting resistor). The current is about 16mA with a 9V supply and current-limiting resistors are not needed.
 

microtexan

New Member
pretty lights, 7 year old thread

What about rather than using multiple 4017's why not have one of 10 outputs drive 3 LED's therefore you have 3 different chains all chasing each other.

Is it for a storefront?
Tom, check the date of this thread.
 

Hero999

Banned
I think he means he wants to power the whole thing off 1.5V - just use a Joule Thief, it's what they're designed for.
 
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