VU Meter Controller Case for NeoPixel powered by Arduino Nano

This VU Meter controller uses an Arduino Nano to control two strings of NeoPixels. It has an LCD Panel to display the status, and a button to control the animation preset and sensitivity. The Nano is mounted on a PCB that can be ordered from one of the inexpensive manufacturers targeting small DIY prints. Alternatively, it can also be built on a prototype 30x70mm board.

Electronics Parts

• Arduino Nano, or compatible
• 1602 LCD Display Module with I2C control
• DC Threaded Barrel Jack
• Tactile button 6x6x5mm 
• Header Socket Connector Strip, 16 pins, × 2 (for mounting Arduino Nano)
• JST-XH Pin Housings (2.54mm), 4pin × 2, 2pin × 2
• 5.5mm Threaded Barrel Panel Jack (for DC power)
• Hookup wire, 22 or 24 AWG
• if using manufactured PCB from Gerber files…
  • Audio Jack - SJ1-3523N
• …or if using 30mmx70mm prototype board
  • Audio Jack - SJ1-3545 (or equivalent)
• Capacitors, THT
  • 10 μF × 2
  • 1000 μF × 1
• Resistors, THT
  • 75 ohm × 2
  • 10K ohm × 5
• 3 Conductor electrical wire (connect to the NeoPixels)
• Connection for NeoPixels - I used JST-SM Connectorss

Mechanical Parts

• M2 Threaded Insert, 4mm × 6 (button mount, PCB mount)
• M3 Threaded Insert, 6mm × 7 (front and back panel mounts)
• M2 bolt, 4mm × 6 (button mount)
  • or 6mm and add a few washers or nut
• M3 bolt, 8mm × 3 (back panel)
• M3 bolt, 10mm × 4 (front panel)

Assembly Notes

• Finished by sanding, acrylic paint, and seal.
• Threaded inserts are inserted after heating them with a soldering iron set to about 10-20% greater temperature than the filament was printed.
  • The back panel doesn't have a great deal of plastic material to set the inserts in - set these on a flat surface and very carefully heat. The joints will be a bit malleable until they cool.
• The internal connection pins:
  • +5V
    • 1) +5V incoming, 2) GND
  • LCD_Connection
    • 1) +5V, 2) GND, 3) SCL [Arduino A5], 4) SDA [Arduino A4]
  • NeoPixel_Connection
    • 1) +5V, 2) GND, 3) Left LED data [Arduino D10], 4) Right LED data [Arduino D9]
    • To wire this to the external JST-SM connectors, first string six hookup wires through the opening in the Back Panel right above the housing, each about 10cm in length. Two Red, Two Black, One Blue and One Green. On the exterior side, strip and crimp into two 3 pin JST-SM housings, Red-Black-Blue and Red-Black-Green. Adjust this for however your NeoPixel strands are configured - some of them come with JST-XH connectors which you may want to replace with SM. I splice one of the red onto the other red wire (see the attached image) about 2cm back from the internal end, and then covered this connection with heat shrink. This is repeated for the black. Then strip and crimp the remaining four wires for the male XH connection.