Instructions

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The flashing LED
The flashing LED contains a transistor as an electronic switch.
In addition, other transistors and other components are re-
quired, which together form a complex circuit and control the
exact timing. Everything is constructed on a small piece of
silicon, which is installed next to the LED crystal.
17 flashing lights – red and green
Now the flashing lights should be extended so that two LEDs
flash at the same time. For this, the green LED is switched in
series to the red flashing LED. In addition, there is a white,
LED the brightness of which can be adjusted with the poten-
tiometer.
This causes both LEDs to flash at the same rate. But if you
look closely, you realise that the green LED never goes out
completely. So even when it’s off, some power will flow
through the blinking LED. The controller in the flashing LED
continues to run and measures the time until the red LED
should be switched on again.