Manual

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T
he sounds that you will hear from this circuit will
remind you of the music you hear in horror movies.
Once you wire the project, use your special light
s
hield and your hand to change the light amount
that shines onto the CdS cell. This changes the
pitch of the music.
The pitch of a sound is determined is by the sound
wave’s frequency, which is the number of cycles of
electromagnetic energy per second. The amount of
light on the CdS cell determines the resistance of
the cell. The more resistance you have the slower
the frequency of the musical sound waves. The
oscillator circuit produces the basic sound wave.
F
requency modulation, or FM, is when the
frequency of an oscillator is controlled by part of the
circuit. An FM radio signal is similar to this but at
h
igher frequencies.
Notes:
EXPERIMENT #10: SOUND EFFECTS FOR HORROR MOVIES
Wiring Sequence:
o 1-29
o 2-30
o 3-47-106
o 4-74-45-42-119
o 5-103-105
o 15-86
o 16-46-104
o 40-113-80
o 41-112-78
o 44-114-83-76
o 120-48-81-79-75-77
o 73-85-84
Schematic
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