-50-
Project 131
Euro Siren
Symphony of
Sounds
Project 130
Machine Gun
Symphony of
Sounds
Project 128
Incandescent
Symphony of
Sounds
Project 126
Symphony of Sounds
This circuit has a lot
happening at once.
Turn on the slide switch (S1); you hear
sounds from the music & alarm ICs (U1 &
U2), and the color LED (D8) lights. Push
the press switch (S2) several times to add
sounds from the space war IC (U3).
A
B
C
D
x
Y
Use the preceding
circuit, but add the
phototransistor (Q4)
across points X & Y
using a 1-snap wire;
the “+” side of Q4
should be towards
U3.
Use the preceding
circuit, but replace
the color LED (D8)
with the lamp (L1).
Use projects 126-
128, but remove the
2-snap wire that is on
top of U2.
Use projects 126-
128, but move the 2-
snap wire of top of U2
one space to the right
(so it is across points
B & C).
Use projects 126-
128, but move the 2-
snap wire of top of U2
to be across points A
& D.
Project 127
Photo Symphony
of Sounds
Project 129
Siren Symphony
of Sounds
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