seoul p4 reds

[jin starkiller]

ok so i don't need the resistor is that what you are saying....first time using rebels

[RevengeoftheSeth]

ok so i don't need the resistor is that what you are saying....first time using rebels

I don't suggest anyone directly power an LED from a un-resistored battery pack. Some people do it. I don't recommend it.

You need to add power to your battery solution, and then use the proper resistor.

[Jedi-Loreen]

Even with no resistor, a 3V battery pack is not enough voltage to properly power that LED.

[jin starkiller]

ok so go up on my voltage got it ...thanks

[BuildaVader]

Regarding the use of a resistor with the red P4, the store suggests using a 4.7 ohm/5 w resistor...but here I read to use a 2.2 ohm/5w resistor. Which resistor would be the better choice for use with the red P4? I wanted to do a LUX III conversion on my older MR saber (3 AA batteries putting out 4.5v) but since LUX III's are no longer to be found, I suppose I wil use the P4 but want the correct resistor.

I have not used a Rebel as of yet, but looking at the specs the lumen output is comparable. The P4's forward voltage is only 2.5 and the Rebel is 2.9. So the P4 seems slightly more efficient. As I have recently learned however the P4 is a little more um.... fragile. (i blew one by not using a resistor despite knowing that others have done so with no issues)

Keep in mind that you will need to order a heatsink shim, lens holder, and lens made specifically for use with the rebel in MHS.

For the P4 (and possibly the Rebel) I would use the 2.2 Ohm 5 Watt resistor sold in the store as well...

Good luck, let us know how it turns out!

[equinox13]

if you're using an MR board, you'll have a constant 3.5V 1000-1200mA coming off of the LED wires on it. to cut that back to a level that won't explode your red P4, you need either a 1 ohm or 1.2 ohm resistor, depending on what your board output is (1000 or 1200mA).

[BuildaVader]

Yes...I do plan on using the origional MR board with my conversion. I'd hate to toast the P4 without the proper resistor.