Maker Factory ELECTRONICS EXPERIMENTS BOX Manual page 246

Fig. 3.15: Circuit 15: Threshold voltage yellow LED
Function of the Circuits 17 and 18: The two transistors T1 and T2 are switching each other on or off with a
time delay. This is caused by the collector potential of T2 that controls the base current of T1 to C1 and vice
versa, the collector potential of T1 which controls the base current of T2 to C2. The values of C1 and R3 or of
C2 and R4 define the time delay and thus the oscillating frequency.
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Fig. 3.16: Circuit 16: Threshold voltage infrared diode
Fig. 3.17: Circuit 17:
Awesome double
turn signal