Author Topic: Multiple Boards Single Enclosure RGB LED help  (Read 193 times)

Advoc

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Multiple Boards Single Enclosure RGB LED help
« on: September 05, 2019, 12:19:48 PM »
Hi my good dudes, I'm looking for a bit of help with an idea.

I have built a triple dirt pedal with the Green Bean, Slow Loris, and Pig Butt, and it's killer.  I haven't yet added any of the indicator LEDs because I wanted to do a light plate, and I find drilling the holes and mounting the LED's to be the hardest part of the final assembly steps, so I just didn't bother with it yet.

My thought, originally, was to do a light plate type of setup, where the corresponding area of the pedal would light up with the color of that particular effect, but when I got to thinking about it, I have quite a few 4-lead RGB Leds lying around.

I think that would be really neat to use because it would give me different colours for each effect as well as blending them together.

To wire the power up, I only grounded the -9V on one of the boards, and used that to ground all of the jacks, switches, and pcbs using the G lug instead of the -9V lug.  Made a lot of sense to me once I started wiring it up.  I get that the top Left lug of the 3PDT switches is for the LED (white in my picture) so my question is:

If I were to use a single 4-lead LED, Hook each anode up to the LED+ on each PCB, where do I hook up the cathode?  Can it be any ground anywhere? Ie. on any one of the PCB boards (and leave the rest of the LED- lugs empty) or to one of the ground spots like the input jack or one of the switches?  If I did that would all 3 switches turn on their respective colour without issue?

Thanks in advance you legends.

« Last Edit: September 05, 2019, 12:21:35 PM by Advoc »

Leevibe

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Re: Multiple Boards Single Enclosure RGB LED help
« Reply #1 on: September 05, 2019, 02:18:47 PM »
Hey. Cool build! I think you will need to get a common anode LED instead of common cathode to make this work. If I were trying it I would ignore the LED pads on the PCBs and bring 9v straight to the anode. Then I would choose resistor values for each cathode that give even brightness between the colors. Then each cathode would be wired to its corresponding switch with its resistor wired between the cathode pin and the switch lug.
« Last Edit: September 05, 2019, 03:38:39 PM by Leevibe »

jimilee

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Re: Multiple Boards Single Enclosure RGB LED help
« Reply #2 on: September 05, 2019, 03:25:13 PM »
Hi my good dudes, I'm looking for a bit of help with an idea.

I have built a triple dirt pedal with the Green Bean, Slow Loris, and Pig Butt, and it's killer.  I haven't yet added any of the indicator LEDs because I wanted to do a light plate, and I find drilling the holes and mounting the LED's to be the hardest part of the final assembly steps, so I just didn't bother with it yet.

My thought, originally, was to do a light plate type of setup, where the corresponding area of the pedal would light up with the color of that particular effect, but when I got to thinking about it, I have quite a few 4-lead RGB Leds lying around.

I think that would be really neat to use because it would give me different colours for each effect as well as blending them together.

To wire the power up, I only grounded the -9V on one of the boards, and used that to ground all of the jacks, switches, and pcbs using the G lug instead of the -9V lug.  Made a lot of sense to me once I started wiring it up.  I get that the top Left lug of the 3PDT switches is for the LED (white in my picture) so my question is:

If I were to use a single 4-lead LED, Hook each anode up to the LED+ on each PCB, where do I hook up the cathode?  Can it be any ground anywhere? Ie. on any one of the PCB boards (and leave the rest of the LED- lugs empty) or to one of the ground spots like the input jack or one of the switches?  If I did that would all 3 switches turn on their respective colour without issue?

Thanks in advance you legends.


In theory, yes, any ground will work. Iím trying to wrap my head around what youíre doing and if it will work.


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HamSandwich

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Re: Multiple Boards Single Enclosure RGB LED help
« Reply #3 on: September 05, 2019, 06:42:25 PM »
Hey. Cool build! I think you will need to get a common anode LED instead of common cathode to make this work. If I were trying it I would ignore the LED pads on the PCBs and bring 9v straight to the anode. Then I would choose resistor values for each cathode that give even brightness between the colors. Then each cathode would be wired to its corresponding switch with its resistor wired between the cathode pin and the switch lug.

Agreed with taking the LED, resistor and switching away from the board and wiring directly with resistors from the +9V to the anode(s). Should make it less dependent on whatís happening on the boards. You could do common anode or cathode this way, and more easily change resistor values if you find some colors are brighter or darker than others. You can run your ground back to anywhere, but try wherever it is youíre Star grounding.

Willybomb

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Re: Multiple Boards Single Enclosure RGB LED help
« Reply #4 on: September 09, 2019, 04:20:22 AM »
You definitely want to use a common anode, that way the cathodes can just go to their relevant switch ground points.

My experience with them is that you don't get multiple colours at once if they're all switched on at the same time, you'll get whichever colour has the lowest forward voltage.  I might be wrong though as I normally use them as Red or Green, or Blue (see my Leviathan build where I have one on a rotary switch that switched between a treble booster, an SHO, or the treble booster into the SHO).

Leevibe

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Re: Multiple Boards Single Enclosure RGB LED help
« Reply #5 on: September 09, 2019, 10:06:25 AM »
You definitely want to use a common anode, that way the cathodes can just go to their relevant switch ground points.

My experience with them is that you don't get multiple colours at once if they're all switched on at the same time, you'll get whichever colour has the lowest forward voltage.  I might be wrong though as I normally use them as Red or Green, or Blue (see my Leviathan build where I have one on a rotary switch that switched between a treble booster, an SHO, or the treble booster into the SHO).

You would definitely struggle to get good color mixing, it at all. I think the right way to do that would be to control them with PWM, which gets over complex.