- Mar 7, 2018
- Reaction score
Friend of mine has a friend who found an amp in a dumpster and gave it to him. It only made a loud hum noise. (None of the controls affect the hum noise at all by the way) He in turn gave it to me hoping i could get it working, so I opened her up and found a burnt resistor. I replaced that part. The resistors I replaced was the big ol square ceramic heat proof type. Afterwards I plugged it in. The loud hum wasnt there but the amp still didnt work. Later on i got out a bright light and decided to look at the parts on the board closer and found a burnt transistor. So I ordered that and replaced it. I thought, wow maybe we fixed her up cheaply with minimal effort. Well when i plugged it in after replacing the transistor, the resistor i originally replaced started glowing and another big ceramic resistor burnt out. There are 2 of these almost next to each other. I replaced that as well. Now when I plug it in the original resistor I replaced glows red. I cant leave it plugged in long or I'll burn that one out again. I only have one more left and I'll have to buy more. I found a blurry schematic online. Near bottom center in what looks like a speaker. On the left of that is where the 2 resistors are. R73 and R74. I'm not great at schematics yet and I still have a lot to learn about electronics. Any help or suggestions on where to look for the reason these keep burning up would be great . Thanks!