Elenco Snap Circuits® Deluxe Sound & Light Combo - Manual (Page 121)

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Project 250 Time Light Project 251
Time Light (II)
The 470mF capacitor (C5)
can store electricity. This
timer circuit works by slowly
charging up C5; the color
LED goes out when C5 gets
full. If you replace C5 with C2
or C7, the LED will go out
almost immediately because
these values can’t store
nearly as much electricity.
Use the preceding circuit, but replace the
adjustable resistor (RV) with the 5.1kW resistor
(R3). The circuit works the same way, but the
color LED can only light over a small part of
RV3’s range, and it gets dim faster.
Build the circuit, and turn on the slide
switch (S1). Push the press switch (S2)
and set the 500kW adjustable resistor
(RV3) so the color LED (D8) just comes
on, then release the press switch. The
color LED will be bright for a while and
slowly get dim and go out. Push the press
switch again to reset the color LED’s timer.
You can change RV3’s setting to keep the
color LED on much longer. The adjustable
resistor (RV) is used here as a fixed
resistor (of 50kW), so moving its lever will
have no effect.
Use the preceding circuit, but replace the
adjustable resistor (RV) with the 5.1kW resistor
(R3). The circuit works the same way, but the
color LED gets dim faster.
Project 252 Easier Adjust
Time Light
Build the circuit, and turn on the slide
switch (S1) Push and release the press
switch (S2). Set the 500kW adjustable
resistor (RV3) so the color LED (D8) is on
and bright, then wait for it to get dim and
go out. Push the press switch again to
reset the color LED’s timer. The brighter
the color LED starts, the faster it gets dim.
The adjustable resistor (RV) is used here
as a fixed resistor (of 50kW), so moving its
lever will have no effect.
Project 253
Small Adjust
Time Light
SCC-350_Manual_Part_C.qxp 7/25/14 2:10 PM Page 9