Very confused by the breadboard / tutorial buying options

Projects General Guidance
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Hello all -- I decided to follow a tutorial to get myself started with arduino, bought some components and now I'm at a bit of a loss.

I am following: https://www.instructables.com/id/Bass-Responsive-RGB-Leds-using-Arduino/

Which seems to have a number of problems with it. I'm extremely confused at

  1. The diagrams don't make a ton of sense to me (w/r/t breadboarding, as I'm still pretty new). From what I understand so far (from youtube tutorials) I am needing to connect things to both positive / negative, and then run them through a ground on the arduino, then connect the LED strip to the same ground (?)

  2. The kit that he recommended in that tutorial doesn't have any capacitors / resistors, which seems like a pretty massive oversight, as he's using them in his images of the completed build.

  3. When plugging in the LED lights, depending on which holes they are plugged into (by pulling it off the arduino board 1 pin at a time) it changes colors, is this what's supposed to happen?

I am still quite new and appreciate any help that you guys can give.

Thanks,

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Hey DjikstraXx! How ya doin'? Are you related to the computer guy from the 80s? He was like a guru to me back in the day. I still program in his diagramatic style.

But anyway, you had some concerns:

  1. Yeah, the diagrams represent where the electricity goes. First you need to learn a little about electric circuits.

  2. Instructables' tutorials are not known for their accuracy or verifiability. You might need to dig deeper into the components used, and other approaches to their use. Some steps may have been left out.

  3. That seems like one of the more benign ways a randomly connected circuit could behave.

Check out the "How to use this forum - please read" thread stapled to the top of this thread listing. Or click here.

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No relation, but he was a family friend, didn't realize who he was until after he was gone though. My father was quite close to him.

  1. I watched a couple of youtube tutorials about breadboards, and I think I have a pretty fair understanding of them, but I'm really confused as to what the PWM's do and what their role in the overall project is.

  2. Using the program that he laid out with some changes to the Java (programming -- not really java but close enough) I was able to see that the music was being processed -- but obviously due to the LEDs not being properly connected that was a no-go. Given what he shows, can you help make an approximation as to what should be going where? I can't really get a feel for what wire is going where on the board as they're so crossed over. Instructables didn't really quality check this one very well.

  3. There was no fire or explosion.... so that was rad.

Thanks again

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DjikstraXx:
3. When plugging in the LED lights, depending on which holes they are plugged into (by pulling it off the arduino board 1 pin at a time) it changes colors, is this what's supposed to happen?

RGB led has 3 different led junctions built into 1 bulb and 4 pins.
On some there is one pin for power (common anode) and one pin to ground (maybe through a resistor or transistor or other component) for each color. The light is controlled through the grounds and all 3 colors share the same power.
The other kind have one pin for ground (common cathode) and you power each color with its own pin and that I like better because shared ground does not make one color junctions less bright when another is turned on.

Either way, you pull a color pin out of the circuit and that junction makes no more color.

All my RGB leds have clear bulbs. They need diffusing to make the bulb or diffuser glow but they do cast light well. Close up I see the colors as little flakes in the bulb but standing back they make little spots of 1 color each.

There are cheaper 2 color leds with colored bulbs. I have red-green leds that look red when the red pin is powered and looks green when the green pin is powered and look amber when both pins are powered. They're good for decorations, the bulbs glow. There are more 2 color leds.

PWM is pulse width modulation usually done by the controller hardware but can be done in software. You have a short time, 1 or 2 ms where your led is full ON for some fraction (the ON pulse width/time) and then OFF for what's left. 100% PWM means ON the whole time, 0% means OFF, in between means some pulse and some LOW. Human eyes can't see that fast, to us the brightness changes with the pulse width. Changing the pulse width is the modulation part. This is also used for motor control.

The why do PWM is because the high efficiency transistors are only so efficient when fully ON or fully OFF, otherwise they heat up. Those transistors are FETs (field effect transistors) and they're worth using PWM rather than valving the output level like BJTs (bipolar junction transistors) have been used to do since the 50's. BJTs can do that but they can't carry much current without heating up, the rule of thumb is BJT is good < 1A while FETs are good with any power not just >= 1A ... I have 2N7777 FETs that have max load at 250mA, for example. They cost me 10 cents each.

Djikstra.... had something to do with Reverse Polish calculating? I had a Bomar Brain for a while, my first RPN calculator.