Quantity   Component name
10 × Wood Slices One slice per letter plus a test piece and extras if you screw up...
1 × Foil Tape Roll HVAC Metal foil tape. Should be foil and adhesive only.
1 × Marker or Pen fine point
1 × Set of letter stencils 2" high or larger
1 × 220 k ohm resistor Through-hole, any wattage
1 × 280 ohm resistor Through-hole, any wattage
2 × 2N2222 Transistor Through-hole transistor - can be other similar NPN transistor.
1 × Phototransistor Through-hole
1 × White LED Through-hole, Straw-hat style
1 × Spool Hook-up wire light gauge hookup wire
4 × Battery terminal springs Harvest these from a battery holder
4 × AA Batteries Harvest these from remotes you don't use
4 × Thick copper wire, 1.5" long I used 14 ga solid copper house electrical wire with the insulation removed
1 × Small drill bit Just bigger than the thick copper wire
1 × Large wood bit Just big enough for the batteries to fit in the holes.