I Want to make Fireworks!

[KenL_MCSE]

Scott, what did you do, I cannot tell by the pics on your site. Kind of looks like chicken wire fence with the lights attached to make the effect? How many lights? I see you said 32 channels... Details please

[ErnieHorning]

ErnieHorning wrote:

When I re-read your response, I now see that you were talking about mini lights. I now think it might work...

Upon further review, there is no way it’s going to work on mini lights. First of all the 2.5 volts per light is dependent on all of the rest. Second, there’s no return path through any of the SCR’s. They’re likely to come on all at once due to leakage if they turn on at all.

I still think that I can sequence C7/C9 bulbs with TRIAC’s. I’ve got a working method with relays but TRIAC’s would possibly be lighter.

[David Conley]

I stole part of this idea from a highschool project. It was called a color organ and used SCR's to provide the switching. You're right...there is no return path. The AC ends up being rectified through the SCR. In this case I plan to throw a bridge at the input and send straight DC down the string. With 20 lights in the string and 20 SCR's in the path I should be able to swap out the bulbs for 1.5 volt ones and maintain the same brightness. Keep me honest...Does it fly now?

[ErnieHorning]

David Conley wrote:

Does it fly now?

David, maybe I just need a new picture because other than swapping out 2.5 volt bulbs for 1.5 volt ones, I’m only picturing the schematic that you already posted.

The biggest problem that I see with this idea is that each bulb is completely dependent on all of the other bulbs being in the circuit too. They all have to be on at the same time to drop the voltage down for each bulb to be at the correct voltage. If any bulb is off, then no bulb will have any voltage. For this to work, you would need to somehow replace all the bulbs that aren’t on with comparable resistors. You would then need to remove the resistor while supplying voltage to the bulb that supposed to come on next.

I can’t see a way to make this work in series. It could be done in parallel but then you would need to use a 2.5 volt DC supply. With .1 amp bulbs, you’d need 2 amps for a 20 light string or 3.4 amps for the more common .17 amp bulbs. This would add up rather quickly if you wanted a bunch of strings.

[David Conley]

Ahhhhhh!!! With all of those tree's in the way I completely missed the forrest. Now I see what you are talking about. What a dummy. I should have seen that. This is exactly why I began this thread. I needed someone to see the error in my ways. There is still hope, though. Parallel still has promise. I need to do some looking and see if there is a lower wattage alternative to C7's I believe that 5 watts is as low as they go.