lightning

[scottyish]

:?: Need help designing a circuit to create lightning effects, preferably with flourescent lights for Halloween. Thanks.

 

[kinjalgp]

What kind of effect do you want? Sequential or random?
If you want sequential effect the simplest method is to use Decade counter IC 4017. The IC has 10 outputs which shift one by one when a clock signal is fed to it. Use 555 IC in astable mode (low frequency) to generate clock for 4017 . The output of 4017 can be used to drive triacs with the help of small signal transistors like BC547. The lamp loads should be connected to triacs.
For Random effect you can use a simple microcontroller. But you got to know the programming of it before using it.

Kinjal

 

[star882]

Try a strobe for the flash.

 

[Mikkel]

The output of 4017 can be used to drive triacs with the help of small signal transistors like BC547.

How do you the drive triacs with the help of small signal transistors?

 

[kinjalgp]

This way:
**broken link removed**

 

[kinjalgp]

This way: The value of R1 is 1k
**broken link removed**

 

[mechie]

Caution

I don't mean to nit-pick but just in case anyone isn't aware ...
The driver circuit above will cause your whole circuit to be potentially LIVE ! - the mains is connected to your logic circuit ground rail so be careful. Make this the mains Neutral (for those lucky enough to have a neutral ?) but NEVER assume it to be a safe voltage !.

 

[kinjalgp]

I have tried it with both ways i.e. neutral and live but in both cases circuit is dangerous to touch sp beware :twisted:

 

[Phasor]

Just a thought - You could use an optoisolated triac driver if you want to separate the logic and the load.

 

[kinjalgp]

Yes even thats a better and safe option. :idea:

 

[Mikkel]

Thanks for the circuit, Kinjalgp

I wanted this circuit because i couldn't get triac optoisolators