Maker Factory ELECTRONICS EXPERIMENTS BOX Manual page 263

Circuit 53: No current flows through LED1 while it is dark. T1 and T2 are blocked. LED2 remains dark. As
soon as light falls on LED1, current flows and T1 and T2 are conductive. LED2 is lit.
Fig. 3.52: Circuit 52: Stimu-
lating mantel clock
Fig. 3.53: Circuit 53: Light sensitive
switch with green LED
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