Elenco LIGHT - Manual (Page 29)

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Project 19 Sound Maker
Build the circuit and turn on the
switch (S1). You hear sound from
the speaker. Adjust the sound
using the lever on the adjustable
resistor (RV), and by pushing the
press switch (S2).
Note: In rare cases the circuit
may not work at all settings on
RV. If this happens, move the RV
lever to the side near the strobe
IC, turn the slide switch off and
on to reset the circuit, and only
move the RV lever over a small
range.
The strobe IC (U23) produces an electrical
“tone”. The pitch of the “tone” is adjusted by
changing how much electricity flows into its
upper-left snap, using a resistor. The electrical
tone it produces can be used to make sound
using a speaker, or to control the flash rate of
an LED see project 20, the Strobe Light).
Project 20
Strobe Light
Use the preceding circuit, but replace the
speaker with the white LED (D6). Now you
have a strobe light!
When S2 is pressed, the light may be blinking
so fast that it appears to be on continuously.
Project 21
Color Strobe
Light
Use the preceding circuit, but replace the
white LED with the color LED (D8).
Project 22
Red Strobe
Light
Use the preceding circuit but replace the color
LED (D8) with the red LED (D1).
The color LED will not be
changing colors like it does in
other circuits. When the strobe
IC (U23) turns the color LED
on and off, it resets the color-
control microcircuit in the color
LED. Even your slowest strobe
speed is too fast for the color
LED.