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Projects => Tech Help - Projects Page => Topic started by: dujuarez on September 23, 2014, 01:45:26 AM

Title: Harbinger One LED
Post by: dujuarez on September 23, 2014, 01:45:26 AM
I just finished the Harbinger One. But before I connect the power (using Dunlop 18v transformer), I was thinking that the LED that I have connected (standard connection, positive from DC Jack to LED to number 3 lug on 3PDT footswitch)might burn out with the 18v. My question is, will it burn out? By the way I have the 4.7k resistor connected to LED.
Title: Re: Harbinger One LED
Post by: jjanssen1 on September 23, 2014, 09:10:30 AM
Hi,
Do you know what the voltage drop across the LED is?
Cheers
Joshua
Title: Re: Harbinger One LED
Post by: copachino on September 23, 2014, 01:29:30 PM
Quote from: dujuarez on September 23, 2014, 01:45:26 AM
I just finished the Harbinger One. But before I connect the power (using Dunlop 18v transformer), I was thinking that the LED that I have connected (standard connection, positive from DC Jack to LED to number 3 lug on 3PDT footswitch)might burn out with the 18v. My question is, will it burn out? By the way I have the 4.7k resistor connected to LED.

i dont think it will burn, since there its a current limiter resistor, so you can go safe if you ask me, its going to bright like hell but i wont burn
Title: Re: Harbinger One LED
Post by: kothoma on September 23, 2014, 02:36:43 PM
Better raise it to about 12k.
Title: Re: Harbinger One LED
Post by: copachino on September 23, 2014, 02:42:10 PM
or probably 10k will b ok, even though i have used 1k for 9v, on 5mm leds, so 4.7k its not going to damage you led, but maybe its too much light than you need
Title: Re: Harbinger One LED
Post by: angrykoko on September 23, 2014, 06:43:00 PM
I used a 10K and though it was fine.
Title: Re: Harbinger One LED
Post by: midwayfair on September 23, 2014, 09:39:05 PM
When in doubt:

http://ledcalc.com/
Title: Re: Harbinger One LED
Post by: angrykoko on September 24, 2014, 06:20:56 PM
Quote from: midwayfair on September 23, 2014, 09:39:05 PM
When in doubt:

http://ledcalc.com/

That's cool. 
It needs one more calculation though "Retina Safe Recommended Resistor".
Title: Re: Harbinger One LED
Post by: dujuarez on October 02, 2014, 04:26:30 AM
Thanks for all the help. I got it going and it sounds great and no problems with the LED. :)