My other hobby is playing guitar. You may ask how that relates to this forum. Well, it's amazing what we can use to help us repair our machines. For my guitar I made a little cigar box travel amp. The beauty of this thing is that it runs on a wide range of voltage, 3v-12v dc, and it's light and portable. It's an easy circuit to build. The only bulk of it is the speaker, but I chose a large one for guitar reasons. Recently, I had to fix the Sounds Good board for my Rampage. There are like 4 op-amps after the DAC. Since the amp is mono, I took an alligator clip from the ground on the amp input to the common ground of the game and clipped a spare DMM probe to the amp input signal line. All I had to do was to probe the output of the DAC and the analog I/O lines of the individual op-amps. Low and behold the second op-amp was getting the input, but no output. Quick socket and new chip and the game is back to 100%. I hope this will help others trouble shoot audio problems in the future.



