Manual

Turn on the slide switch (S1). The white LED (D6) lights dimly.
Now push the press switch (S2) and hold it down. The white and
color LEDs (D6 & D8) appear to be alternately flashing.
Project 124
Use the preceding circuit but add the white
LED (D6) on level 4 using one 1-snap wire, as
shown. The white LED will light when the LEDs
in the light tunnel turn off.
The sound changes
whenever the LEDs in the
light tunnel turn off for a
moment. The horn sound is
louder here than in project
124 because the control
current from the light tunnel
is amplified by the NPN
transistor (Q2) instead of
controlling the horn directly.
-67-
Project 126
Loud Multi-Multi-
Color Sound
Project 125 Loud Multi-
Color Sound
The sound changes
whenever the LEDs in
both the color LED
and light tunnel turn
off for a moment.
Alternating Lights
Turn on the slide switch (S1). The light
tunnel (U30) is changing colors and sound
from the horn (W1) is synchronized with it.
The color LED (D8) is intentionally
installed backwards and will not light.
In this circuit electricity to the white and color LEDs is
restricted by the 5.1kW resistor (R3). The color LED
(D8) contains separate red, green, and blue LEDs, with
a microcircuit controlling them.
Red and green LEDs turn on more easily than white
LEDs, so when the red or green lights in the color LED
are on, all the electricity through the 5.1kW resistor
flows through them, and the white LED is off.
Blue & white LEDs have similar turn-on characteristics,
so when the blue LED in the color LED is on, both it
and the white LED light dimly as the electricity flowing
through the 5.1kW resistor is divided between them.
All the LEDs in the color LED shut off briefly when it
changes colors; when this happens the white LED is
on as all the electricity flowing the the 5.1kW resistor
flows through it, as if the press switch was not pressed.