This post will walk you through the building of a netArt firefly.
You will make two fireflies on one breadboard. Each firefly consists of a photocell circuit that sense changes in light, and an LED circuit that emits light. We will use bright white LEDs ( supplied in class) but you can build with a regular LED for now and we will swap parts when we meet.
Goal
Build two (2) fireflies on a single breadboard. The fireflies will be controlled by an Arduino Uno.
Each firefly consists of an LED powered through a TIP122 and a photocell circuit for reading light. We will put two fireflies on a single breadboard. One will get yellow wires, the other blue. Please follow the colors.
All of you know the photocell circuit. So that one should feel like review / refresh.
You should also all know how to blink a basic LED (even if the process is rusty).
Experience with a TIP122 – will be spotty .
Given this, here is a link that discusses TIP122 transistors:
It would be a great refresher (or introduction), as it covers the circuit we are making. It has a 10min video.
Parts list:
General:
- 1 UNO
- 1 breadboard
- USB cable for programming
- Battery pack, barrel connector, batteries.
Power Connections:
- 2 RED jumper wires – breadboard width(for 5V)
- 2 BLACK jumpers – breadboard width (for ground)
- 2 BLACK jumpers – short(1-2cm) for TIP ground.
Firefly Connections:
- 2 YELLOW jumpers – long (10-12 cm)
- 2 BLUE jumpers – medium (7-10cm)
For two FIREFLIES (half for a single fly):
- 2 – 10K fixed resistor ( brown, black, orange)
- 2 – photocell
- 2 – 1k fixed resistor ( brown, black, red)
- 2 – 470ohm resistor (yellow purple brown)
- 2 – TIP122
- 2 – simple LED (red,or green, or yellow)
- 2 – bright WHITE led ( delivered in class – you don’t have these yet)
Final Firefly Setup
