madbeanpedals::forum

Projects => General Questions => Topic started by: Spenzerleehorton on November 12, 2016, 05:25:53 AM

Title: Harbinger one Build
Post by: Spenzerleehorton on November 12, 2016, 05:25:53 AM
Hi,

I'm just starting to build ten Harbinger one pcb and noticed a wrong value on R48, on PDF it says 12k, but I'm pretty sure this is a typo and meant to be 1.2k.

Regards

Spence.
Title: Re: Harbinger one Build
Post by: Road2k on April 10, 2017, 06:49:43 AM
Did you try 1.2k?
Title: Re: Harbinger one Build
Post by: AntKnee on April 11, 2017, 02:13:09 AM
I'm not familiar with this circuit, but it is 12k in the BOM and the schematic. What leads you to think it should be 1k2?
Title: Re: Harbinger one Build
Post by: midwayfair on April 11, 2017, 02:39:04 AM
That's the current limiting resistor for the bypass indicator, dude.

1.2 will put about 12mA through a red LED with an 18V supply. While this certainly won't hurt the LED, it would be extremely bright and waste a totally unnecessary amount of energy. The 12K limits it to under 2mA.
Title: Re: Harbinger one Build
Post by: AntKnee on April 11, 2017, 01:39:32 PM
I didn't even look to see what its purpose is. LOL

Spence, while you can vary the value of the CLR to get the desired brightness of the LED, you don't want to waste power and make the pedal use more energy than necessary. I prefer to use 10k for my CLR on 9v builds, so a 12k CLR on an 18v build is right where it should be. It could probably be even higher if you're using a water clear or ultra bright LED.