Fixed-Voltage Divider; Simple Illumination Meter - Elenco Electronics Snap Circuits Instruction Manual

Project #485
Project #486

Fixed-Voltage Divider

OBJECTIVE: To make a fixed current path.
The meter (M2) indicates the amount of current in the circuit. Turn on the
switch (S1), the needle deflects indicating the amount of current. The
10kΩ resistor limits the current, otherwise the meter could be damaged.
Simple Illumination
Meter
OBJECTIVE: To make a simple light meter.
Using only a few parts, you can make a simple light meter. The
amount of light changes the resistance of the photo resistor (RP),
which affects the current though the meter (M2). As light increases,
the resistance drops and the meter deflects to the right. Decreasing
the light, the meter deflects to the left, indicating less current.
Set the variable resistor (RV) to the far left and turn on the switch (S1).
The circuit is now very sensitive to light. Wave your hand over the
photo resistor (RP) and the meter deflects to the left, almost to zero.
Move the adjustable resistor to the far right and see how less sensitive
the circuit is to light now.
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