Manual Part 2

0.5mA

Project 16 | TIMED WALL OF FUN

The lights, fan, and sound are on while capacitor C5 is charging,

then stop as the capacitor gets fully charged. Pressing S2

instantly discharges the capacitor and resumes the fun. The

circuit would run longer if you used a higher value resistor or

capacitor, because then the charging would take longer.

Assembly:

1. Place the base grid support on base grid B.

2. Place parts on grids C and install into base grid supports on grid B.

3. Install remaining parts on grids A&B.

Set the meter (M6) to the 0.5mA scale, push the press switch (S2), and then

turn on the slide switch (S1). The motor (M4) spins the fan, the LEDs (D6

& D8) light, the melody IC (U32) plays a tune, and the meter measures the

current charging the 470µF capacitor through the 5.1kΩ resistor. The meter

shows the current decreasing and soon everything stops. Push the press

switch to re-start the circuit.