Project 345 little battery, Project 347 little battery beep, Project 346 tiny battery – Elenco Snap Circuits® Deluxe Sound & Light Combo User Manual
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Project 345
Little Battery
Set the knob on the 500kW adjustable resistor (RV3) to the
left. Place the color LED (D8) across the points marked B &
C (“+” to B); the LED lights as the capacitor charges. Next,
place the color LED across points A & B (“+” to A) instead;
now the LED lights as the capacitor discharges. Move the
color LED back to B & C and repeat. Use the knob on RV3
to vary the charge / discharge rate, but keep it close to the
left (otherwise the LED would be too dim to see).
The capacitor is storing energy like a little battery.
Project 346
Tiny Battery
Use the preceding circuit, but
replace the 470mF capacitor (C5)
with the smaller 1mF capacitor
(C7) or 100mF capacitor (C4). Set
RV3 all the way to the left. Place
the color LED across B & C to
charge C7, then across A & B to
discharge it. The LED will only
light briefly with C4, and will only
flash for a moment with C7,
because C4 and C7 can’t store
much electricity (C5 holds 470
times more than C7, and 4.7
times more than C4). The LED is
easier to see in a dimly lit room.
Set the knob on the 500kW adjustable
resistor (RV3) to mid-range. Place the
470mF capacitor (C5) across the
points marked B & C (“+” to C), then
SWING its “+” side around to point A
(without unsnapping it from point B).
Swing its “+” side between points C &
A several times.
When the capacitor (C5) touches point
C, the color LED (D8) flashes to show
that the batteries charged up the
capacitor. When the capacitor touches
point A, you hear beep from the
speaker (SP2) to show that the audio
circuit discharged the capacitor.
You can change the “beep” sound a
little by turning the knob on RV3.
Batteries can hold a lot
more electricity than
capacitors
because
batteries store chemical
energy while capacitors
store electrical energy.
Project 347
Little Battery Beep
The capacitor is storing
energy like a little battery.
The “beep” you hear is the
voice changer (U27) entering
recording mode, but you
can’t make any recording
with this circuit. Capacitor C5
can’t store enough electricity
to operate the voice changer
circuit, but it can power it long
enough to make a beep.
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