Chaotic Flashing - Maker Factory ELECTRONICS EXPERIMENTS BOX Manual

2.41 Chaotic flashing

Circuit 96: Two LED in Waltz time
Setup information
Install the two transistors, the two LEDs, the four resistors and the three electrolytic capacitors as shown in
Fig. 2.96. Finally, insert the 13 jumper wires. Check the placement on the board and only then connect the
battery.
Experiment
Even if everything is wired correctly, nothing will happen at first. It takes a while until the circuit moves into
gear. The small asymmetries need to charge an electrolytic capacitor first upon switching on so that one of
the transistors can switch through. But then the slow waltz kicks into gear.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.96.
Components required:
2 x 2N3904 transistors,
1 x red LED, 1 x green
LED, 2 x 220 kΩ resis-
tors, 1 x 2.2 kΩ resis-
tor, 1 x 1 kΩ resistor,
1 x 100 μF electrolytic
capacitor, 2 x 10 μF
electrolytic capacitors,
1 x breadboard, 1 x 9V
battery with clip con-
nector
Fig. 2.96: Two LED in Waltz
time
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