Would this be correct for nano biscotte v2

[Forgetful Jedi Knight]

You need to REALLY go over Ohm's Law. The speaker has nothing to do with the resistor calculation. In addition, the wattage is only half of the "equation" anyway.

[clahey83]

if you are not that great with math just do a google search for LED resistor calculator. you will need your source voltage (3.7) the voltage drop for your LED (reds are usually 2-2.3V look up what yours is) and your desired amps. 700mA is safe for reds.

[bionicmad]

From your method it has said a 2w resistor is required.

[Forgetful Jedi Knight]

From your method it has said a 2w resistor is required.

This is only half of it, you also need to know what "Ohm" rating you need.

[bionicmad]

The ohms was 2.2 and the w was 2w

[Forgetful Jedi Knight]

The ohms was 2.2 and the w was 2w

OK, that will work.

[parsaver]

I have a similar set up in mind. I did this math for a rebel Tri Deep Red (2.4V , 700mA), a NBv2 and a Li-Ion 18650 3.7V 3400mAh PCB. It looked like this: 3.7v-2.4v/.7= gave me 1.85ohm I was going to use this http://www.thecustomsabershop.com/15...istor-P13.aspx

Is this the correct math? It is my understanding that resistors are like the price is right, as close as you can get without going over?

Thanks and sorry to jump on your thread.

[Silver Serpent]

Generally it is safer to always round up on resistor values, not down. Jump on up to the 2.2ohm resistor. http://www.thecustomsabershop.com/22...istor-P11.aspx

[parsaver]

Generally it is safer to always round up on resistor values, not down. Jump on up to the 2.2ohm resistor. http://www.thecustomsabershop.com/22...istor-P11.aspx

Thanks!! After 8 years I'm finally building one lol

[Silver Serpent]

I'm willing to bet that it won't take 8 years before you start on your second. This hobby is addicting, the only limit is the depth of your wallet.