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# Help a beginner project.

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#### Tlarsen93

##### New Member
I am building an entertainment board for my niece. It will have all kinds of things for her to play with and develop her motor skills on including various types of latches and locks. I want to include an assortment of four LEDs and three small motors that spin her favorite cartoon characters each activated by a different type of switch (toggle, rocker, temporary push button, key activated, chain pull...) . I have the carpentry part down and everything is mounted but I don't know the best way to wire them to a single battery pack.

Each LED is 12v 10mm and says it has a built in integral resistor on the package.

The motors are rated .5-3.0 v

Would 4 AA batteries be OK to power the board? (I am intending only one thing be on at a time but she is a kid and will probably turn on multiple)

In summary, I have a battery power supply, four LEDs with a switch next to each one and three motors with switches next to each one. How do I connect them?

I would only use two AA batteries to power the motors, as two AA batteries in series will power the motors. If you connect all the AA batteries in series you will have 6V.
Chances are that the LED's may not show on with 4 AA batteries if the do they may be real dim. Do the motors have a +(positive) and - (negative) lead? The way the motors are hooked to the battery thru a switch will determine the direction of rotation. Do the LED's have a +(positive) and - (negative) lead?. The LED's will only light if the polarity is correct. I would see if the LED's lite up. Connect the +(positive) lead of one LED to the +6V, connect the - (negative) lead of the same led to the - lead of the 6V battery. If the LED lights up great.
I would would connect all three -(negative) leads of the motors to the - lead of the batteries. I would connect one lead of each switch to the junction of the second and 3rd AA batteries in series. Then I would connect the other lead of each of the switches to + (positive) lead of the motors. When each switch is turned on that motor will spin.
I would connect the - lead of each of the LED's to the same - lead of the batteries that you connected the motors too. I would connect 1 lead of each of the LED switches to the + terminal of the 4th battery. This will be 6V. Connect the other lead of the 4 switches to the + lead of the LED's. When each switch is turned on the LED connected with light up.

For my Grandson:
Powered form a 12 volt wall wort. (power supply form a small rechargeable drill)
Lights are for cars. Safe voltage.
Door bell. Button switch and buzzer.
Two types of switches.
Two colors of lights. Red & Yellow
Two types of doors. One has a mirror inside.
Door knocker.
Spring Door Stop, Makes a funny noise when you pull on it.
The wheel is from a walker. Fun to spin. Now he pretends to drive.

Attaches to the side of the refrigerator. Made from smoked plexiglass.

The plan is to add one thing every week. Now the weeks are 30 days long.

Thank you for the responses. They were very helpful. I like the idea of using a 12v rechargeable drill battery. This should be fine for the 12v LEDs but would I need resistors for the motors because they are 3v? Is it as simple as wiring an appropriately sized resistor in series with each motor?

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The wiring for the motors with the 12V battery is not an easy thing. In simple terms the amount of current that the motors consume varis with the voltage, as a result the resistors would have to be variable. The best is with a step down regulator. In other words a module that has 12V in and 3V out. I you live in the USA I could build you one that would work. I have all the parts to build something like that. The cost would be minimal including shipping. If you are interested, start a converstation with me for details.

3V or 12V ?? Do what is best for you.
With 3V motors I think a 3V battery is better. (two 1.5v batteries or two 1.2V rechargeable)
I wanted to get all the parts at the auto store. The electronics store(s) are gone.
You can use LEDs for lights (with 3V)

you could do this...
drawn in paint so sorry about that

Or this,
So each motor only see 3V but its one battery per motor so they all have about the same loading and life.
The LED sees 12V as its across all 4 batteries.
again sorry for it being in paint

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