Making Good Solder Joints
Learning Morse Code
Learn to spot the common soldering mistakes, and you
will quickly learn to solder. Many beginners forget to heat
both the pad and the pin, ending up with solder on only
one of the two things they are connecting. Make sure the
soldering iron touches both, and apply the solder to the
opposite side of the joint. A good solder joint looks like a
little volcano with the sides sloping down.
The first time you try translating Morse Code, it may
seem impossibly fast. First concentrate on identifying
which are dots and which are dashes. Once your ears
learn the difference, write down the dots and dashes
as you hear them. Write fast and leave spaces on
your paper where there are spaces between the
sounds. After the Morse Beepy plays the longer,
lower-pitched sound after the message, it will go to
sleep. Then take your time translating the symbols
you wrote using this chart of Morse Code.
Things were moving
while solder cooled
Not enough
solder on pad
Too much
solder
A •–
P •––•
4 ••••–
B –•••
Q ––•–
5 •••••
C –•–•
R •–•
6 –••••
D –••
S •••
7 ––•••
E •
T –
8 –––••
Programming
F ••–•
U ••–
9 ––––•
The microcontroller we used on the Morse Beepy has
been programmed to do what we want. For this project,
we programmed it to send riddles in Morse Code.
G ––•
V •••–
. •–•–•–
H ••••
W •––
, ––••––
I ••
X –••–
: –––•••
J •–––
Y –•––
? ••––••
K –•–
Z ––••
– –••••–
L •–••
0 –––––
( –•––•
Message 3: Riddle B question
M ––
1 •––––
) –•––•–
Message 4: Riddle B answer
N –•
2 ••–––
@ •––•–•
O –––
3 •••––
OK
OK
Image by http://www.adafruit.com
The microcontroller has a list of messages in its
memory. Each riddle counts as one message, and the
riddle’s answer counts as one message. Like this:
Message 1: Riddle A question
Message 2: Riddle A answer
And so on…
It also has a place in its memory called a variable
where it records the number of the message to play
next. When we first program the Morse Beepy
microcontrollers, that variable has the first message’s
number stored in it (1). After playing that message, it
adds one to the variable, or resets the variable to “1” if
the variable is greater than the total number of
messages.
Simplified, the programming goes something like this:
When the microcontroller wakes from sleep:
Play greeting or “CQ CQ CQ”.
Play the next un-played message.
Record that message as played.
If that was the last message:
Set the first message to be next.
Play low-pitched sound.
Go to low-power sleep mode.
What Next?
Use your curiosity and imagination to drive your
learning adventure. Information and help are all over
the place. Think of a project you want to do, and find
the help and knowledge to do it.
If you want to do more electronics or robotics, check
out the tutorials and supplies at www.adafruit.com,
www.sparkfun.com, and www.pololu.com
If you are interested in programming more, try the
fun and free coding activities at www.code.org
Morse Beepy
Brains
We give the
microcontroller a list of
instructions to follow,
turning the power to the
buzzer and the LED on and
off at the right times to
create Morse Code.
Light
The Light Emitting
Diode, or LED, converts
electricity into light.
Button
This button wakes the
microcontroller from
sleep so it can run its
program.
Hidden Connections
The circuit board connects everything
together, using flat strips of copper
instead of wires. These flat strips are
hidden under a protective purple mask,
except where they meet the components
for soldering. Simplified versions of their
paths are shown by this schematic.
Power
The battery supplies
energy to the circuit.
Sound
The piezo buzzer
converts electricity into
vibrating motion, which
makes sound.