Color Cycling LED

[Bricksnbeatles]

I know the microcontrollers in color-cycling LEDs can inject noise into a pedal signal occasionally if it’s used for the status indicator. I’ve seen it said that putting a cap or two across the LED can filter out that noise, so I’ve got a pair of questions for y’all that have used them:

1. What cap value(s) did you find were able to filter the noise out
2. Has it always worked for you, or do you still get noise from the μC oscillator in some higher-gain circuits?

It’s easy enough to test out, but I figure I might as well find out other people’s experiences before I start in case it’s s waste of time. I’ve only ever used the color cycling LEDs as power indicators for standalone Cornish buffers, and noise has never been an issue there, so I don’t know what to expect as far as the supposed noise issues go.

 

[benny_profane]

I’ve only ever used the color cycling LEDs as power indicators for standalone Cornish buffers

Whoa. Gilding the lily there a bit. Too much excitement.

That aside, I don’t have anything useful to contribute.

 

[BryGuy]

I have one in a pedal I made a while back. It is a madbean mood ring so it kind of fit the theme. I can confirm it does inject some noise but only when changing colors. So every few seconds there is a bit of hum as the color changes. I actually didn’t notice it at first but now that I know it’s there I can’t un-hear it. Never tried to filter it out so I would be curious what other have done as well.

 

[t2smet]

I've just tried one of those color changing led in my new conqueror fuzz, it gave me a whole lot of loud crackling while roughly half the colors were displayed, and kept quiet for the other half... unusable as it is, but I'd like to find out how to isolate it from the circuit... I ordered flickering leds, i wanted to install one under the tube on my next tube driver build, I'm guessing I'll get some noise from that too ...if anybody has a suggestion ?

 

[jhaneyzz]

I've just tried one of those color changing led in my new conqueror fuzz, it gave me a whole lot of loud crackling while roughly half the colors were displayed, and kept quiet for the other half... unusable as it is, but I'd like to find out how to isolate it from the circuit... I ordered flickering leds, i wanted to install one under the tube on my next tube driver build, I'm guessing I'll get some noise from that too ...if anybody has a suggestion ?

Keep us in the loop on this. I like this idea...

 

[Bricksnbeatles]

I've just tried one of those color changing led in my new conqueror fuzz, it gave me a whole lot of loud crackling while roughly half the colors were displayed, and kept quiet for the other half... unusable as it is, but I'd like to find out how to isolate it from the circuit... I ordered flickering leds, i wanted to install one under the tube on my next tube driver build, I'm guessing I'll get some noise from that too ...if anybody has a suggestion ?

Try a 10uf cap across the led. Filtered out all of the noise from the color cycling led in my harmonic energizer. The led isnt as smooth anymore (it stays on red for a while longer, skips yellow, and both green and purple are fairly short in the cycle, but it’s still rather nice looking.

 

[t2smet]

Try a 10uf cap across the led. Filtered out all of the noise from the color cycling led in my harmonic energizer. The led isnt as smooth anymore (it stays on red for a while longer, skips yellow, and both green and purple are fairly short in the cycle, but it’s still rather nice looking.

Thanks, excellent, I'll try that !

 

[Cybercow]

I’ve successfully used color-cycling LEDs under transparent-shafted pots with transparent knobs and as bypass indicators by applying a 100nF & 1nF caps in parallel across them. If using a CLR with them, be sure the CLR is inside the paralleled caps.

 

[Bricksnbeatles]

If using a CLR with them, be sure the CLR is inside the paralleled caps.

Interesting- I haven't tried that orientation, but haven't had any issues. What difference do you see from that?

 

[Cybercow]

Interesting- I haven't tried that orientation, but haven't had any issues. What difference do you see from that?

TBHG, I did not try that configuration with the CLY outside the paralleled caps. I imagine it should be fine. I was just thinking to completely isolate the color-cycling LED and it's CLR to reduce the µPU noise. It will likely work either way. I just haven't tried it.