Manual

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Antenna: This cylindrical component with a coil of
fine wire wrapped around it is a radio antenna. If
you’re wondering what the dark colored rod is, it’s
a
ctually mostly powdered iron. It’s also known as a
“Ferrite Core”, which is efficient for antennas, and
used in almost all transistor radios.
Transformer: Did you know that if you were to wrap
two wires from different circuits around different ends
of an iron bar, and if you were to add current in the
first circuit, it will magnetically create current in the
second circuit? That’s exactly what a transformer is!
Transformers are used to isolate parts of a circuit, to
keep them from interfering with each other.
If the iron bar in a transformer were allowed to rotate,
it would become a motor. However, if a magnet
within a coil is rotating then an electrical current is
made; this is called a generator. Those two ideas
may not seem important but they are the foundation
of the present society. Pretty much all of the
electricity used in this world is generated by huge
generators, which are propelled by water pressure or
steam. Wires transport energy to homes and
businesses where it will be used. Motors are used to
convert the electricity back into mechanical form so
that it can be used to drive machinery and
appliances.
Speaker: Did you know that electrical energy is
converted into sound through a speaker? By using the
energy from an AC electrical signal it creates
mechanical vibration. Sound waves, which are
created by variations of vibrations and then travel
a
cross the room. When you hear a sound it is actually
your ears feeling the pressure from the air vibrations.
To operate a speaker a high current and a low voltage
are needed, so the transformer will also be used with
the speaker. (A transformer can convert a high-
voltage/low current to a low-voltage/high current).
Similar to the speaker, is the earphone. It is movable
and more sensitive than the speaker, otherwise they
are the same. The earphone you will be using is
efficient as well as lightweight and can be used
without taking away too much electrical energy from
the circuit. Sound wise you will be using the
earphone for weak sounds and for louder sounds the
speaker will be used.
Batteries: The battery holders that are used in this
kit are constructed to hold six (6) “AA” batteries.
These batteries will be the supplier of all the power
used in your experiments. When you connect the
wires to the batteries make sure that you only
connect the batteries to terminals noted. Terminals
119 and 120 provide 3 volts while terminals 119 and
121 provide 4.5 volts. Be aware that parts can be
damaged (burned out) if you connect too much
voltage (you can get up to 9 volts from the
connections to the batteries) Be sure to make battery
connections the right way.
Caution: Make sure your wiring uses the correct
polarity (the “+” and “-” sides of the component)!
Some parts can be permanently damaged if you
reverse polarity.
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