ThatGuy
Neat idea of adding Christmas lights to engines and I will be coping it unless you patent it!
On your update on the circuit please give more details on the min LEDs you used like number LEDs in the string, Volts for each bulb and for the whole string and maybe Walmart ID number. There are dozens of such Christmas LED lights to choose from and more details will make it easier for us to copy your fine work.
Thanks
Charlie
Unlike what you might do for normal LED lights, many of these "micro fairy LED light strings" (the typical names they are advertised under) they are a whole bunch of LEDs in parallel. Normally this would be ill advised unless the LEDS are so perfectly matched, but for simplicity reasons, it appears to just be how they are mass manufactured using typical magnet wiring with the insulation removed every so often and a tiny SMD LED inserted.
As such- you power the string typically with enough forward voltage to light the highest voltage color- typically white or blue, but then also limit current using a series resistor with the string.
As an example, MTH is feeding their multicolored strings with 6V regulated DC, and typically 100 to 150 Ohm resistor for current limiting.
Again, often you can buy these in bulk. I've seen AAA battery pack versions, 2 CR2032 coin cells in series. The 3 cell pack gives 4.5V nominal, where 2 coin cells being 3V each is 6V- again very similar to what MTH is using.
