Launch Controller System for 3 Rockets

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Mar 26, 2009
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I have made a basic Launch controller to the specs provided at I have added 3 toggle switches and a plug for an external power source.

What I need is help with the wiring of the added components. Basic instructions will really help since I am not really electrically savvy. I have tested the basic set-up and am able to get the lamp to light using a direct connect of 4 AA batteries.

A) How do I connect the toggle switches so that I can select individual rockets or launch all 3 at once?

B) How do I get the external power to work? I have connected the same 4 AA batteries, however the power does not work. Do I need a larger power source?

Thanks for any help.

Last edited:
Michael, an explanation of basic electricity can take up a whole semester college course. If you know nothing about electricity, a quick explanation would be to think of it as water in a hose. The voltage would be like the water pressure, the current would be the volume of water flowing. Resistance would be anything that slows down or restricts the flow and switches work as shutoff valves. The only thing to remember is that unlike a water hose, electricity has to have a return path. That's why there are + and - terminals on batteries. After connecting one side to all the components that do work (lamps, LEDs, igniters), you need to have a return from each that allows the electricity to flow back to the battery. Switches are controlling components and can be inserted in the main + wire, or the - wire.

As for the switches to turn on or off each pad, you should have the three wires going to each of the three pads, coming off the launch button. Put a toggle switch in the + wire for each of the wires between the launch button and the pads.

As for swapping power sources. Each power source, if it's the internal batteries, or an external source, should be connected to the controller circuits by two wires, the + and -. You need a connector of some sort in these two wires so you can disconnect one power source and plug in another. Just remember, if you are switching from a 6 volt power to 12 volt power, you will need to change any light bulbs in the circuits because 6 volt bulbs will burn out using 12 volts, and 12 volt bulbs may not light with only 6 volts.

Hope that helped and didn't confuse matters.
Thanks Handeman,

That does help. I have attached a photo of what I have so far and where I want to go from here.




I will install the next 2 toggle switches and complete the wiring and let you know how it comes out. Your power source explanation makes complete sense however I am having problems even getting the same 6 volt power source from working through my external connections. I'll keep playing.

Thanks again,

Thank You Handeman!!!

I just needed that extra push. I have completed the controller and all looks to be working. I will test it with several rockets tomorrow.



Here is the finished product:



Took the controller out to test it and it worked perfectly. Unfortunately it was a windy day and I lost a few rockets but thats OK. Now I can create some new ones.

As for pictures - I didn't take any but I will get some on the next launch.