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please i need help.

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sleyk

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hello everyone pls i need help, i want to flash 20LED bulbs without a
555 timer IC, but i have tried it with a 31v DC 2.021Amp a capacitor of 10V 100µf and a resistor of 2700? well it flashed for once and it got blown.
pls i will like to have the accurate value of capacitor and resistor, also what is the real voltage to be used.
 
hello everyone pls i need help, i want to flash 20LED bulbs without a
555 timer IC, but i have tried it with a 31v DC 2.021Amp a capacitor of 10V 100µf and a resistor of 2700? well it flashed for once and it got blown.
pls i will like to have the accurate value of capacitor and resistor, also what is the real voltage to be used.

hi,:)
Please explain how you connected the 'blown' circuit.
How do you expect to flash LED's with just a capacitor and resistor.?
 
hello everyone pls i need help, i want to flash 20LED bulbs without a
555 timer IC, but i have tried it with a 31v DC 2.021Amp a capacitor of 10V 100µf and a resistor of 2700? well it flashed for once and it got blown.
pls i will like to have the accurate value of capacitor and resistor, also what is the real voltage to be used.

I think your going to have to add some details here about how you want them to flash. Does it need to be at a specific frequency? Does it need to be a stable frequency?


I have always ment to make that reverse bias oscillator just to see it work, but never think of it when I am board. lol
 
Wait a minute. That thing works? What do you mean "no connect". So the base floats? It must be very random if it does. But still....It works? That would be slick. I bet you could blow on it and it will change frequency, if it actually works that is.
It is very random and does work with all transistors.

I don't know how reliable it is, it might even damage the transistor as it isn't designed to be used in the manner.
 
hello everyone pls i need help, i want to flash 20LED bulbs without a
555 timer IC, but i have tried it with a 31v DC 2.021Amp a capacitor of 10V 100µf and a resistor of 2700? well it flashed for once and it got blown.
pls i will like to have the accurate value of capacitor and resistor, also what is the real voltage to be used.

I assume that you allowed too much current to go through, also did you have a resistor to protect the LED's?

You need to plan things like these, for instance did you connect them in parallel or in series?
 
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It can be done with a resistor, capacitor and relay - much like a homebrew flasher. I tried this to save money on a flasher for Christmas lights, but settled for optos and triacs ( safer!). Why do you need a high voltage?
You could also use a clock generator made from NAND or NOR gate ICs, with a suitable driver transistor. An LM3909 LED flasher IC would also work.
 
Wait a minute. That thing works? What do you mean "no connect". So the base floats? It must be very random if it does. But still....It works? That would be slick. I bet you could blow on it and it will change frequency, if it actually works that is.

It works. Stick to the suggested values, though. Experimenting with other cap and resistor values, even voltage, will produce varying degrees of success.

An atomic clock it ain't. But it does make a LED blink.
 
sleyk,

Are you saying that you want to connect a resistor and capacitor in series
and then suddenly switch these to connect between a power supply and
20 LEDs in series?

If this is the case, you need a cap that is rated for more than 10v because
the final voltage across the cap would be the same as the power supply.

You would also have to specify what color LEDs you are using so we would
know the forward voltage drop for each LED. You might also have to
connect them in series/parallel to get the right voltage level.

There are better ways to do this of course.
 
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