Data Sheet

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31. Ship-to-Ship Morse Code
Press the press switch (61), the LED (69) will blink. This can
be used as a Morse code typing simulator. Morse code uses
various sequences of long and short on-off tones, lights or
clicks to represent letters, numbers, and text. Since World
War II, the process for sending messages using signal lamps
has barely changed. It requires someone trained in Morse
code to operate the lamp’s shutter by hand, receiving,
decoding, and replying to messages.
32. Reversing a DC Motor
Build the circuit to the left. Press and hold the press switch
(61) and the fan blade (60) will spin clockwise. Release the
press switch (61), the motor (95) will stop. Now put the
motor (95) in backwards using 3-wires (3) instead of 2-wires
(2). Press and hold the press switch (61) and the fan blade
(60) now spins counterclockwise. Notice that the direction the
motor (95) spins is related to the direction the current ows
through the motor (95). This is because the force created on
the motor shaft is related to the direction that the current
ows through the magnetic eld in the motor (95). You can
look up Fleming’s left hand rule for more details on how the
relationship between the current ow, magnetic eld and
force that creates motion.
WARNING: Moving parts. Do not touch
the fan or motor during operation. Do
not lean over the motor.
!