ok! Finally the amp IS working!
After changing very carefully one SMT, I liked the procedure, and started to change the possible faulty ones until the amp was fine! I started from TS15, TS16 & TS17 and ended with TS3, TS7, TS2 & TS6. One of the last ones were the faulty one! No dc at the output. I rebiased the amp and did an offset adjustment for 0mV at the output and the amp now is on my bench with an 8 Ohm resistive dummy load and a signal generator at the input and delivers clean 100W.
But how can I be sure that the amp won't blow any other pair at the future? Last time it blew the output stage plus C3 cap after a few weeks. Coincidence?
Was it because I changed only one pair and not a "matched" quartet? What was the problem?
After changing very carefully one SMT, I liked the procedure, and started to change the possible faulty ones until the amp was fine! I started from TS15, TS16 & TS17 and ended with TS3, TS7, TS2 & TS6. One of the last ones were the faulty one! No dc at the output. I rebiased the amp and did an offset adjustment for 0mV at the output and the amp now is on my bench with an 8 Ohm resistive dummy load and a signal generator at the input and delivers clean 100W.
But how can I be sure that the amp won't blow any other pair at the future? Last time it blew the output stage plus C3 cap after a few weeks. Coincidence?
Was it because I changed only one pair and not a "matched" quartet? What was the problem?
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