Dirtbaby 2015 LED Question D2

[fair.child]

Should the D2 on the Dirtbaby 2015 be on all the time? I am having issue with the current build and planning to debug during this weekend. I have seen and reviewed the build docs though it says in 2016 that D2 is used to reduce potential distortion at the input of the
PT2399. It should not be mounted to the enclosure (it does not light up).

If it does light up in my case, where should I start to debug it?

[somnif]

Did you use the green diffuse LED recommended? (the color matters in this case)

[fair.child]

AHh, that could be the reason. I didn't use the green led instead I used red LED. I'll give a shot

[Boba7]

I remember searching for green leds that had a voltage drop around 2 and 2.2v
The led will light up when the signal is too strong and gets limited by the led.

[somnif]

I remember searching for green leds that had a voltage drop around 2 and 2.2v
The led will light up when the signal is too strong and gets limited by the led.

Yeah basically the LED is there to prevent over-driving the 2399's processor. Anything over ~2.5V causes a really ugly, nasty type of "broken" distortion. So, Midwayfair came up with the idea of putting a diode on pin 7 that would shunt to ground any signals over that. Diffuse green LEDs have an fV of around 2.3V, so they are by far the closest solution without getting into specialty parts. Red LEDs tend to have fV's closer to about 1.5V, so it doesn't really work to serve the same purpose.

You can read more about the story here: http://www.diystompboxes.com/smfforum/index.php?topic=101149.0