Fix Marshall guitar amplifier
My wife and I go to an Okinawan pub close to our flat. The meal in Okinawa is delicious and healthy. We have been to the pub a lot of times, so we got close to the owner in the pub.
One day, he asked me to fix his guitar amplifier. I agreed (his request) and connected my guitar to the amp in our flat. The amp made a sudden loud sound. If the knob turns, the amp makes a rasping sound. I tried to clean the contacts of the switch, the potentiometers, by using special spray, but unfortunately the rasping sound didn't leave. I ordered new the switch and the potentiometers and replaced them. The rasping and sudden loud sound stopped.
I brought the amp back to the pub to return it. He smiled and thanked me. I was very glad that I have electric circuit skill. My job is not related electric engineer, but I felt that I can help with some electric problems.