Multifunctional LC Oscillation Circuit Demonstrator

1. Circuit Principle

As shown in the figure below, K1~K3 are normally open switches, L1 and L2 are 25W/220V incandescent lamps, Cl~C4 are 150μF/400V color TV high-voltage electrolytic capacitors, connected to form non-polar capacitors, L is a 160W (220V/12V) transformer, D is 1N4007, R is 500Ω, and LED is a high-brightness light-emitting diode.

2. Production process

Put a 40cm×33cm five-ply board upright on a 40cm×20cm wooden board base, fix the transformer on the wooden board base, fix the lamp holder, normally open switch and capacitor according to the circuit diagram 9 after the five-ply board is fixed, use φ1.5mm soft-skinned copper wire for the connecting wire, and make the normally open switch with the keys on a toy electronic keyboard, solder all the components, and seal all the soldering points with glass glue to ensure insulation.

3. Usage

(1) Charging and discharging of capacitors Insert the power plug into a 220V AC socket, close K1 to charge the capacitor, L1 will light up until charging is complete and L1 turns off. Then close K2, the capacitor will discharge to L2, L2 will light up until it turns off.

(2) LC electromagnetic oscillation Insert the power plug into a 220V oscillating current socket, close K1 to charge the capacitor, and the light bulb L1 will light up until L1 goes out, and the capacitor is fully charged. Close k3, and the capacitor C and the primary coil of the transformer form an LC oscillation circuit, and the LED will light up. The electromagnetic oscillation in the EC oscillation circuit is synchronized, and the LED will light up once. This demonstrator can display 7 cycles of oscillation.