1.5 months. That’s how long it took for my long-awaited package to finally arrive after being stuck at customs forever. In my impatience, I had reordered the components, hoping to meet my deadline, but, alas, the replacements didn’t arrive in time either. And then, just as I was waiting for the results of my EC, the first package finally showed up.
I thought this marked the end of my struggles. “Now everything will fall into place,” I told myself. Little did I know, I was about to enter the next chapter of chaos.
First, I realized I had ordered the wrong versions of several crucial parts:
- The ADAU1701, MT3608, and LM386 chips I received were all surface-mount devices (SMD) instead of the breadboard-friendly through-hole versions I needed.
- My two 18650 batteries were not equipped with proper holders, leaving me unable to securely connect them to the circuit.
Desperate Measures: Fixing What I Could
Some parts weren’t entirely unusable but required modifications:
- The speaker terminals didn’t fit the breadboard, so I had no choice but to cut off the connectors and solder two iron leads onto it. Surprisingly, this worked.
- The PAM8403 amplifier module arrived without pre-soldered headers. My first attempt at soldering was a disaster: I ruined one board entirely. Later, during testing, I managed to burn another board alongside an LED. Ouch.
Mic Troubles
The microphone module wasn’t spared from my chaotic tinkering. Initially, I soldered thin wires to its pins, but the connections were fragile and unreliable. I finally replaced the wires with stiff iron leads, which improved the stability.
SMD Soldering: The Ultimate Test
The three critical SMD chips—ADAU1701, MT3608, and LM386—needed legs soldered to their minuscule pins. Time was short, so I began with the largest of the three: the LM386. Hours passed, and my soldering efforts ended in failure. With only frustration to show for my attempts, I had to admit defeat.
By now, it was clear I wouldn’t have time to reorder or even replace the damaged components. Every misstep added more pressure, and the clock was ticking faster than ever. Despite these setbacks, I resolved to make the best of what I had.
This project has been an ongoing lesson in perseverance, problem-solving, and patience—more than I could have ever anticipated.
Substitution Attempt 1
Facing the mounting challenges with the original plan, I turned to a replacement solution. I decided to use Arduino as an intermediary to process the microphone signal. The idea was simple: connect the microphone to Arduino’s analog input, use analogRead to capture the signal, and then output it through a PWM pin to simulate an analog signal for the speaker.
At first, it felt like progress. I could finally hear something through the speaker—a sign that the signal chain was functional. However, the result was far from ideal. What came out of the speaker was an extremely loud mid-high frequency tone, more noise than meaningful audio. It was frustrating, but also fascinating—a clear reminder of how tricky real-time audio processing can be without proper filtering or amplification stages.