EE 230 Final Project

The goal for this project is to achieve using one switch to control two different LEDs through wireless transmission.



At the oscillator part, we made two oscillators in order to emit two frequencies. One oscillator is to emit 1k Hz frequency which is the frequency to lighten the red LED, and the other oscillator is to emit 10k Hz frequency in order to lighten the green LED. The next step, we connected the circuit to a voltage divider circuit, since the output voltage was too larger for both LEDs. When the signal has transmitted from infrared LED (transmitter) to the light sensor (receiver), we used a diode as a rectifier to convert the AC to DC, which makes LED lights emit consistently. Then a band-pass filter was required to separate frequencies into a high frequency and a low frequency. However, we found the receive signals were too small, hence we built a amplifier to boost the signals’ intensity. Eventually, the LEDs were able to work independently through one switch.



My job in this project was to design the blueprint of the whole project and schematic simulation. I need to understand the functionality of each component so that I am capable to calculate the corresponding values such as resistance, capacitance that fitting the requirement. Especially during the hands-on experiment, we might confront many issues such as how to setup the measurement. From this experiment I learned how to utilize the knowledge to solve the real problem, and additionally I got deeper comprehension on the concepts I have learned on the class. I have benefited from cooperation with my partner. They provided many good ideas that optimized the project outcome.