Need Help Wiring Some LEDs Inside a Prop Pistol

[markanator13]

I know outrageous huh!?

But its the only weapon I'm going to make for now! I have a basic sketch drawn, so take a look...

I don't even know if this is going to work. I have no knowledge in electronics lol!
Can someone help me out!? :$

Comment on what you think is right or wrong, or just in general, Thanks for reading!

 

[Shadow1336]

I think it'll work.

 

[Carpathia]

I've got a great link to a circuit designer that will calculate the required resistors based on what sort of LED's and power source you have. As soon as I get home from work, I'll post the link here.

Edit: HA! Don't have to wait till I get home, here it is...

http://led.linear1.org/led.wiz

So, based on what you've got, I think your design will work, but it's overkill on the resistors.

 

[NovaBombScottie]

It's kind of hard to tell what exactly you're trying to do. Have you tried making a really simple drawing of it in paint? Are the two LED's Different sizes/Desired Brightnesses? If they are the same size, they should have the same Resistors for the same Brightnesses. Just trying to help.

Edit: Something like this?

 

[markanator13]

I've got a great link to a circuit designer that will calculate the required resistors based on what sort of LED's and power source you have. As soon as I get home from work, I'll post the link here.

i googled "Ohm scale" or something and got linked to this "electric guru" thing and i just guessed on all of it..
12V power
5.95V drop
@ 20 mA
with 3 LEDS

and i used common sense to finish the rest, lol! But i still need it to be "approved" i guess, before i buy the LEDS and resistors..

 

[thatdecade]

Electrical engineer here. I can tell you now that a 5.6ohm resister will blow out your poor yellow leds. I'll do a sketch and post back.

 

[wook111]

since they are all the same LED color and im going to guess birghtness as well..... one resistor is needed and one only.... either before all the LED's or AFTER all of them.... dont put it inbetween and the value of 330ohm looks right... it might be a little dim on the LED..... i usually used 220ohm on RED LED's... im pretty sure it would work at 260ohm for the yellows let me double check on that....im just wondering why youre going to be using 12v .... its a little bit of an odd voltage considering a 9v batt is 9v LOL and it would take eight AA's to make 12V and that would make it heavy...i would recommend a single square 9V battery for those items

edit with the values in the last post with colors here

forward volts of 2.15
forward Ma of 20
volatage of 9

it would take a single 150ohm resistor
if you havea bulk pack of resistors the color code is brown green brown with a 4th gold band meaning -/+5% and now i will design you a schematic to work from....

 

[thatdecade]

FYI, the battery voltage isn't so important. A 12V battery will push 36mA through a 330ohm resister which is within the acceptable range for the average LED.

Ok, first of all, each LED needs it's own resister and source to the battery to maximize brightness. Hope the drawing below makes sense, kinda cannibalized your drawing. The battery should last about 6 hours.



A 9V battery would be much easier to work with as they are readily available and inexpensive. A 9V would push 27mA through a 330 ohm resister. This is still above the 20mA rating of the LED so the LED will appear very bright.

Personally, with 9V batteries I use 500 ohm resisters. The exact resister value is not so important. Just use what you have available to you. Something between 100 and 600 is the sweet spot.

 

[markanator13]

Awesome! I will be buying the parts this weekend and will post pics later on!
Thanks!

 

[wook111]

here we go..... i got my shcem

 

[markanator13]

Looks pretty do-able. I'll switch to a 9v Battery and use..
3-470resistors.. http://www.radioshack.com/product/index.jsp?productId=2994588
i was also thinking about these..
http://www.radioshack.com/product/index.jsp?productId=2062321

other than that, I will get the parts this weekend over at radioshack! lol

 

[thatdecade]

Sounds like you have a plan. Good luck