Project 93
Flash & Tone
Project 92
Touch & Go
Connecting the output of the Alarm
or Music ICs to multiple devices
(such as the LED, speaker and
lamp) enables these devices
operations to be synchronized.
Wet your fingers with some
water or saliva and touch
them across points A and B
several times to hear some
space war sounds. Push
the press switch (S2) to
hear more sounds at the
same time.
This circuit uses your body
to conduct electricity, and
turn on the circuit. Wetting
your fingers improves the
connection between the
metal and your finger.
Turn the switch (S1) on and the lamp (L1) and color LED (D8)
start flashing. You hear two different tones driving the LED and
lamp. ICs can be connected to control many different devices
at the same time.
Project 91
Music AND Gate
You will only hear music
if you turn on the slide
switch (S1) AND press
the press switch (S2).
This is referred to as an
AND gate in electronics.
This concept is important
in computer logic.
Example:
If condition X
AND condition Y are
true, then execute
instruction Z.
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