User manual

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however, will be dimly lit due to the small base current still
flowing though that other transistor.
It is impossible to predict the LED that will turn on. You can
however switch the state by bringing a wire in contact with
one of the base terminals, which will generate a short electri-
cal pulse due to charges present at random. More often than
not, it doesn’t always work the first time. But you can do it
safely by connecting the base to the emitter at the currently
conducting transistor.
The flip-flop
A flip-flop is a circuit that knows two stable states. The existing
state is stored for as long as you do not alter it on purpose.
The flip-flop is therefore also an information memory. In our
case, only one piece of information is stored. We could call it
yes or no, but also one or zero, or in our case, we call it red
or green. Many of those flip-flops together form the computer
memory that stores large amounts of data.