Manual

Project 75 Series of LEDs
Build the circuit and turn
on the slide switch (S1).
The white and color LEDs
(D6 & D8) should be
blinking but may be dim.
If neither lights at all then
replace your batteries.
This circuit has both LEDs connected in SERIES. Series circuits are simple
to connect, and allow one component to easily control another (here the
white LED blinking is controlled by the color LED’s blinking). The LEDs may
be dim because the battery voltage may not be high enough to make both
bright. If one LED breaks, then the circuit is broken and neither will work.
The slide switch (S1) is also connected in series with the LEDs, so it can
turn them on and off.
Compare this circuit to the project 75 circuit. This circuit has both LEDs
connected in PARALLEL. Parallel circuits make components independent
of each other but require more complex wiring (notice how this circuit
requires more parts than the project 75 circuit). Both LEDs are bright
because each gets the full battery voltage, but they will drain the batteries
faster. If one LED breaks then the other will still work.
Project 78 Parallel LEDs
Build the circuit and turn
on the slide switch (S1).
The white and color LEDs
(D6 & D8) are bright now
and only the color LED is
blinking.
Use the preceding circuit but replace the white
LED (D6) with the horn (W1). The color LED is
bright and blinking, and the horn is loud.
Compare this circuit’s performance to project 76.
Use the preceding circuit but replace the color
LED (D8) with the white LED (D6). Compare this
circuit’s performance to project 77; the white LED
is brighter, and the horn is louder.
Project 79
Horn & Color Light (II)
Project 80
Horn & White Light (II)
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Use the preceding circuit but replace the white
LED (D6) with the horn (W1, “+” side towards
S1). The color LED lights but may not be blinking,
and the horn may not be very loud. (Electrical
noise generated by the horn can disrupt the
color-changing circuitry in the color LED.)
Use the preceding circuit but replace the color
LED (D8) with the white LED (D6).
Project 76
Horn & Color Light
Project 77
Horn & White Light