Reducing Bright &$$ LED's

knightrider358 · Post by **knightrider358** » Sun Aug 02, 2009 7:08 pm

Ok guys u saw where I did my own custom RDDP. http://phoenixphorum.com/cat5-rj-45-wir ... 11030.html

Now if you noticed LEDS are freakin BRIGHT as the sun I swear at night looks like I got a bunch of neons inside. Wells anyways I was thinking of tinting the LEDs to dim them a little. But then I was like hey I can add a resistor to the leds to reduce the voltage coming out of the amps and the brightness should dim. Now my questions guys is what size resistor should I add. Now the voltage coming out of the amps for RDDP's is 3 volts so Im thinking of 2 volts or 1.5 should be just right. I would greatly appreciate any insight on this. Or a different idea to reduce the brightness.

Post by **ttocs** » Sun Aug 02, 2009 8:24 pm

By adding a resistor you will change the voltage as well as the current. Not sure what that could do to the RDDP output.

andy600rr · Post by **andy600rr** » Sun Aug 02, 2009 11:32 pm

http://www.hebeiltd.com.cn/?p=zz.led.re ... calculator

Should help you out

SolacE · Post by **SolacE** » Mon Aug 03, 2009 3:13 pm

you could replace them with some leds that do not have as much light output or possibly coat them with some spray tint.

Post by **ttocs** » Mon Aug 03, 2009 3:24 pm

I would look into those options before you started adding resistance to the circuit.

I have a black-candy spray that I used to tint my tail-lights that would be perfect for this, I have used it on plexi as well.

76Trans Am · Post by **76Trans Am** » Mon Aug 03, 2009 3:40 pm

Put your shades on

knightrider358 · Post by **knightrider358** » Mon Aug 03, 2009 4:09 pm

LOL trans am

ttocs it shouldnt do anything to the RDDP output because the resistor does not reverse anything as per say it jus will reduce the voltage going into the LED. Ive used plenty of resistor's on HO fans for amp installs to keep the motor from burning up and Ive used them on LED's jus to look cool when I was younger to tell me when an amp would just be on. LOL Im 99% sure it wont cause any problems.

Thanx for all the input guys.

Thumper88 · Post by **Thumper88** » Mon Aug 03, 2009 4:14 pm

Just get an assortment of 1/4 watt resistors...try 200 ohm...100 ohm...etc..see what suits your needs.
The resistor won't do anything harmful, it will only limit the current draw of the LED...nothing more, nothing less...thus "dimming" the LED.

knightrider358 · Post by **knightrider358** » Mon Aug 03, 2009 4:17 pm

thanx thumper I jus couldnt remember what wattage to use thanx for the tip.

Post by **ttocs** » Mon Aug 03, 2009 4:32 pm

knightrider358 wrote:
ttocs it shouldnt do anything to the RDDP output because the resistor does not reverse anything as per say it jus will reduce the voltage going into the LED. Ive used plenty of resistor's on HO fans for amp installs to keep the motor from burning up and Ive used them on LED's jus to look cool when I was younger to tell me when an amp would just be on. LOL Im 99% sure it wont cause any problems.

Thanx for all the input guys.

putting a resistor on a fan or a normal led will work fine as those circuits will not be hurt by limiting its input. The leds will certainly work as a normal led with its voltage limited. As I said I am not sure how well the rddp output is designed to handle changes in its circuits resistance and what it might effect in the amp that supplys that RDDP output. I am sure you will let us know what happens, good luck.