Manual

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D
o you want to become an amateur radio ham?
Many radio operators started out using an oscillator
w
ith a tone control like this one. Listening to the
same tone for a long time can be very tiring, so the
tone control in this experiment can be very helpful.
Simply connect the wires for this circuit and your
code practice oscillator is ready for use.
Morse Code is a code system that uses dots and
dashes, invented by Samuel Morse. The most
effective way to learn Morse Code is to find
someone else who is interested in learning the
code. Set up a schedule and practice every day.
Create a progress chart so you can see your
improvement. Take turns sending and receiving,
and it won’t be long until the code becomes almost
like a spoken language. Operating the key becomes
automatic. It takes hard work to get to this point, but
you’ll be proud when you do.
You can also use different tones to make up your
own special code.
If you want to practice by yourself simply use the
earphone. Disconnect the speaker and connect the
earphone to terminals 27 and 28. Now, the control
acts as a volume control as well as a tone control. If
you want a fixed tone and volume, just replace the
control with a fixed resistance.
When you adjust the control for less resistance, the
0.05mF capacitor charges faster, making the
frequency (and the tone) higher. The opposite
situation occurs when the control is adjusted for
more resistance.
N
otes:
EXPERIMENT #114: MORSE CODE OSCILLATOR WITH TONE CONTROL
Wiring Sequence:
o 1-29
o 2-30
o 3-87-105-109
o 4-124
o 5-41-110
o 85-106-40-27
o 28-88
o 86-42-137
o 119-138
o 121-122
Schematic
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