I try to find a best way (cheap schematics and parts) to make a dynamic Christmas lights form LED's (15-40 piece's). That diagrams must work on 220 V 50 Hz. I search onto forum and nothing came up. So, any advice (a diagrams will be awesome) will be appreciate.
Generally, it's best to use a microcontroller to control different chains of lights.
Do you want to use LEDs or incandescents?
LEDs are probably the best way to go as you can power them from a transformer. Using a 24V 12VA transformer you could connect them in strings of about 10 and will provide enough current for 17 chains giving a total of 170 LEDs!
Small transistors like the BC548 could be used to control the LEDs from the microcontroller which could be powered from a linear regulator like the LM7805.
Do you have a diagram for that ? As you say LED's are better. The only thing I am worry about is the heat. Do you know how much heat is dissipated form that LED's?
Hot LEDs don't stay hot for very long, but then again they don't light afterwards either...
After Christmas, you can get strings of 35-40 LEDs for about $2.00 USD each. I got lucky last year and remembered to look for them. Got 3 strings all white, and 7 multi-color. All but 2 sets had full leads.
If you want to control 40 or more LEDs individually from a micro, look into multiplexing...
Sometimes it's better to build your own even if it does work out more expensive as so long as you design and build it to a high standard you'll get a high quality product.
Design a circuit to fade multi-color RGB LEDs and they make every color that is possible if they fade in a "random fashion".
My MOOD LIGHTS fade their red, green and blue LEDs at slightly different frequencies so the colors on the ceiling are all colors possible and at all brightnesses. The fading is very slow. It repeats in a few hours. It looks cool.