[nathanalaneller]

I was making a mod to my Mech Tommy 10, so I could load darts without turning on the dart launcher motor.

I put an LED light on the switch to indicate the gun was armed or not & it burnt out. I need help on what to put on the LED so it wont burn out again.

Here's the circuit padern.

[Exo]

nathanalaneller, on 20 April 2012 - 09:39 AM, said:

Yeah, you're going to need a resistor in the same path as the LED. Those things usually can't handle 4.5v.

[ThatBritishGuy]

For 4.5V use a 220 or 330 ohm resistor. That will keep it bright and safe if you decide to upgrade to a 9V as well.

[nathanalaneller]

ThatBritishGuy, on 20 April 2012 - 11:09 AM, said:

For 4.5V use a 220 or 330 ohm resistor. That will keep it bright and safe if you decide to upgrade to a 9V as well.

wich side of the LED do I conect it to? + or -

( I only know how to make simple wire circuit's, Im not up to date on how to read chip's & resitor's )

[ThatBritishGuy]

Connect it to the positive side.

Colors on a 220 ohm are red-red-black-gold

[Aeromech]

To add on to the advice in this thread, LEDs are rated for potential and current (Volts and milliamps.) Check for those ratings on the packaging and be sure to stay within those limits in the future. Some knowledge of basic circuits may be required, but an internet search or physics course should provide a good estimate of the potentials and current you will be facing in the future.

[ShaNayNay]

1. use this resistor:

This is what I use in an engineering class with 5v, so it should work perfectly. Keep in mind though that it also resists the motors. The resistor and the LED will take a noticeable amount of power from the motors, and your shots will have less range. I suggest attaching a second battery pack and hiding it somewhere inside the gun. What I did with my T20 is attach a 9v to the motors and put in inside the gun. Then I took the old battery holder and wired it to a flashlight I modded into the gun.

So yeah, I personally suggest a different power source for the LED.

[nathanalaneller]

ShaNayNay, on 20 April 2012 - 02:24 PM, said:

1. use this resistor:

This is what I use in an engineering class with 5v, so it should work perfectly. Keep in mind though that it also resists the motors. The resistor and the LED will take a noticeable amount of power from the motors, and your shots will have less range. I suggest attaching a second battery pack and hiding it somewhere inside the gun. What I did with my T20 is attach a 9v to the motors and put in inside the gun. Then I took the old battery holder and wired it to a flashlight I modded into the gun.

So yeah, I personally suggest a different power source for the LED.

The first thought I had was have a switch to turn off the motor wile loading, then I thought add a light to indicate the power was on or off.

[ShaNayNay]

Oh, I see. Using that resistor should still lessen the power of your motor anyway. You could just get rid of the trigger lock, I think that would be much easier than all that wiring and whatnot. Up to you however.

This post has been edited by ShaNayNay: 21 April 2012 - 02:26 PM

[Darthrambo]

Do you mean a tommy 12 or 20? As far as I know there is no tommy 10.

[nathanalaneller]

Darthrambo, on 23 April 2012 - 08:20 PM, said:

Do you mean a tommy 12 or 20? As far as I know there is no tommy 10.

[Darthrambo]

nathanalaneller, on 23 April 2012 - 08:33 PM, said:

Yeah that's a tommy 20.

Did you put in an on/off switch and make it trigger reving? Its kinda hard to tell from your diagram but it kinda looks like that is the case.