[BEGINNER] - First WS2812 Project - only first LED lights - Help?

Hi, I bought a 12 RGB WS2812 ADDRESSABLE LED RING hooked it up as in this youtube video at 3:23 => 100 Addressable LED Lights Arduino Build (Quick) - YouTube. (Basically wired: 5V transformer to capacitor to arduino with 470ohm resistor between data pin 6 and Din connection on LED ring.)

Downloaded code from Adafruit_NeoPixel/examples/strandtest_wheel/strandtest_wheel.ino and changed number of pixels to 12.

Problem: Only first LED is lighting up. The others are dead. Troubleshooting attempts: Swapped LED ring, but same problem. Hard coded LED number in setPixelColor to 0 and it worked. Changed to any other value and it didn't work.

HELP PLEASE What could the problem be? How can I troubleshoot? Should next step be to get a WS2812 strip and see if that works? (Bought the rings at $10 to save spending $30+ on a strip and then play with code and "addressability" of LEDs.

Thanks in advance for your help

Did you try the different LED variants?

//   NEO_KHZ800  800 KHz bitstream (most NeoPixel products w/WS2812 LEDs)
//   NEO_KHZ400  400 KHz (classic 'v1' (not v2) FLORA pixels, WS2811 drivers)
//   NEO_GRB     Pixels are wired for GRB bitstream (most NeoPixel products)
//   NEO_RGB     Pixels are wired for RGB bitstream (v1 FLORA pixels, not v2)
//   NEO_RGBW    Pixels are wired for RGBW bitstream (NeoPixel RGBW products)

Thanks for the suggestion. I've tried all combinations of the parameters and the best result was the same as what I had, one LED going through the colour test. (:confused: argh)

The other detail I overlooked was that the board is an Elegoo Uno R3 (i.e. clone). After reading some more about 'Arduino vs. Elegoo', I'm going to stick with Arduino, not for technical reasons, but to support the Arduino team. I got the Elegoo as Christmas gift.

Are there any other details about your hardware setup that you forgot to disclose?
Where’s your code? (i.e. the actual code you are running)

If you checked different (new) rings.. and you got the same result, the most likely it is your set-up or more so.. the code.

You are using the DEFAULT Adafruit code linked to above?

Side note: you can get these neopixel rings for MUCH cheaper than $10 for a 12 led ring!