Elenco Snap Circuits Motion - Manual (Page 54)

Build the circuit and turn on the slide switch (S1). Bang on the table or
tap on the vibration switch (S4) and a light comes on. The light stays on
for a while after the vibrations end. The lever on the adjustable resistor
(RV2) controls the maximum light brightness and how long the light stays
on after vibrations end; the brighter the light, the faster it shuts off.
Project 97 Adjustable Slow Off
Vibration Light
Project 100
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When vibration is detected, the 1mF capacitor (C7) is charged
through the vibration switch (S4). When vibrations end, the
capacitor discharges through the resistors in the pivot stand
and RV2, and through the NPN transistor (Q2). The light stays
on as the capacitor discharges. RV2 also limits the current
through the LED (D10), and so affects the LED brightness.
You can make the light shut off faster after vibrations end by
disconnecting C7, or by connecting the black jumper wire
across the pivot stand.
Project 98
Color Slow Off Vibration Light
Use the preceding circuit but replace the red/yellow
bicolor LED (D10) with the color LED (D8, “+” on top).
You can also keep the red/yellow bicolor LED in the
circuit but reverse its orientation, so it makes yellow light.
Project 99
Very Slow Off Vibration Light
Use the preceding circuit with either the D8 or D10
LEDs, but replace the 1mF capacitor (C7) with the
larger 100mF capacitor (C4). The circuit works the
same but the larger capacitor will keep the LED on
longer. Set RV2 to the left side or the LED may seem
to stay on too long.
Modify the preceding circuit
to be this one. Turn on the
slide switch (S1). Bang on
the table or tap on the
vibration switch (S4) and a
light comes on. The light
stays on for a while after the
vibrations end. The lever on
the adjustable resistor
(RV2) controls the
maximum light brightness
and how long the light stays
on after vibrations end; the
brighter the light, the faster
it shuts off.
Bright Slow Off
Vibration Light
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