Elenco Electronics 202 - Manual (Page 66)

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Project #138 Static Symphony
OBJECTIVE: To combine sounds from the
integrated circuits.
OBJECTIVE:
See project #138.
Project #139
Static
Symphony (II)
Project #140 Capacitors in Series
OBJECTIVE: To compare types of circuits.
For a variation on the preceding
circuit, you can replace the 6V
lamp (L2) with the LED (D1), with
the positive (+) side up, or the
motor (M1) (do not place the fan
on it).
Build the circuit shown. Note that in some places
parts are stacked on top of each other. Turn it on and
press the press switch (S2) several times and wave
your hand over the photoresistor (RP) to hear the full
spectrum of sounds that this circuit can create. Have
fun!
Project #141 Capacitors in Parallel
OBJECTIVE: To compare types of circuits.
Turn on the slide switch (S1), then press and release the press switch (S2). The LED (D1)
becomes bright when the 470
μF capacitor (C5) charges up with the press switch on, then
the LED slowly gets dim after you release the press switch.
Now turn off the slide switch. Repeat the test with the slide switch off; you’ll notice the LED goes
out much faster after you release the press switch. The much smaller 100
μF capacitor (C4) is
now in series with the 470 μF and so reduces the total capacitance (electrical storage capacity),
and they discharge much faster. (Note that this is opposite to how resistors in series work).
Turn off the slide switch (S1), then press and release the press switch (S2). The LED (D1)
becomes bright when the 100
μF capacitor (C4) charges up with the press switch on, then
the LED slowly gets dim after you release the press switch.
Now turn on the slide switch and repeat the test; you’ll notice the LED goes out much slower
after you release the press switch. The much larger 470
μF capacitor (C5) is now in parallel
with the 100 μF and so increases the total capacitance (electrical storage capacity), and they
discharge much slower. (Note that this is opposite to how resistors in parallel work.)