Data Sheet

Morse Code: The forerunner of today’s
telephone system was the telegraph,
which was widely used in the latter half
of the 19th century. It only had two
states - on or off (that is, transmitting or
not transmitting), and could not send the
range of frequencies contained in human
voices or music. A code was developed
to send information over long distances
using this system and a sequence of
dots and dashes (short or long transmit
bursts). It was named Morse Code after
its inventor. It was also used extensively
in the early days of radio communica-
tions, though it isn’t in wide use today. It
is sometimes referred to in Hollywood
movies, especially Westerns.
A . _
B _ . . .
C _ . _ .
D _ . .
E .
F . . _ .
G _ _ .
H . . . .
I . .
J . _ _ _
K _ . _
L . _ . .
M _ _
N _ .
O _ _ _
P . _ _ .
Q _ _ . _
R . _ .
S . . .
T _
U . . _
V . . . _
W . _ _
X _ . . _
Y _ . _ _
Z _ _ . .
Period . _ . _ . _
Comma _ _ . . _ _
Question . . _ _ . .
1 . _ _ _ _
2 . . _ _ _
3 . . . _ _
4 . . . . _
5 . . . . .
6 _ . . . .
7 _ _ . . .
8 _ _ _ . .
9 _ _ _ _ .
0 _ _ _ _ _
MORSE CODE
Project 85 Morse Code
This simple circuit can be used for communication.
Push the press switch (S2) in long and short bursts to make a pattern of light flashes rep-
resenting the dots and dashes shown in the Morse Code table shown. You can use Morse
Code and this circuit to send secret messages to some friends in the room without others
knowing what you’re saying.
If you have a strong flashlight or searchlight then you can send messages to friends far
away at night. During World War II Navy ships sometimes communicated by flashing
Morse Code messages between ships using searchlights (because radio transmissions
might reveal their presence to the enemy).
Decode this Morse Code message:
. . . . . . _ . . . _ _ . _ _ .
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