Audio Amplifier
This was one of my first electronic projects. I was required to plan, design, prototype and build a two-stage audio amplifier. It was something I had never done before, but now after having successfully completed it, I definitely look forward to projects like these.
Planning
Planning mainly involved using an excel sheet to keep a record of everything, setting up deadlines to complete the various tasks and keeping track of progress. Good planning and organisational skills were essential to complete the project efficiently within the timeframe.
Action
The first stage of the amplifier was an active bandpass filter which would amplify the audio signal and the second stage was a power amplifier/ buffer amplifier which would provide the current to drive a speaker. I performed the calculations and chose the required components. I completed the prototyping in different stages, first being the active bandpass filter with a dual power supply, second being the active bandpass filter with a single power supply and the final one being both the active bandpass filter along with the power amplifier using a single power supply. After the prototyping, I also designed a PCB for the amplifier and soldered all the components onto the circuit board. The final testing was performed at the end, after the components were soldered, which included taking measurements and an audio test.
Result
The design worked quite well. The output audio was clear and audible, without any noise or distortion. The PCB design was also highly appreciated by my teachers and I also received excellent grades for the project. The pictures below show the final assembled amplifier.
Learnings and Improvements
Firstly, this project helped me to develop excellent organisational and planning skills especially required for technical projects like these. I gained some experience in prototyping electronic systems, designing PCBs and circuits, writing technical reports and efficiently using excel for recording data, creating charts and tables.
Next time, I would pay attention to minute details, as using a wrong value resistor had led me to re-do a measurement which was time-consuming and tedious.