Robot Building for Beginners, Third Edition

CHAPTER 22 ■ SOLDERING AND CONNECTING

Examining the Tube LED Circuit Schematic

You can skip the tube-glowing circuit if you want, since it’s purely for aesthetics. However, the schematic in
Figure 22-26 shows how easy it is to make.

Figure 22-25. Glowing center tube

Figure 22-26. Schematic of the tube LED circuit

The LED colors aren’t listed on the schematic, but you’ll want to select an LED color that contrasts
with the color of the plastic tube you choose. Choose the highest-brightness LEDs you can find because the
opaque plastic of the tube absorbs much of the light. Wide-angle LEDs are desirable, as they’ll light the tube
evenly rather than having a few obvious bright-spots.