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First I would like to comment how great this forum and the people contributing to it are. I have made considerable progress diagnosing this amp by researching this forum. Here is the scenario: One speaker connected to each of the AMP 1 output jacks. Playing music rather quitely from an i pod into channel 1. One of the speakers accidentally got unplugged. Then I made the lethal move and plugged it back in!!!! Wooops. The music stopped and the amp didn't smell too good. I didn't see any smoke though! The main 6 amp fuse was fried. A new one blows as soon as the power is switched on. I found 4 of the 8 transistors under the heat sink are shorted internally. I removed them from the board and retested them with the same results. So I put the heat sink back on (without the center 4 transistors) and reassembled the amp. The fuse does not blow and the the amp works if I put the speakers in the AMP 2 jacks and turn up the monitor controls. The closest schematic I found was for a PX700DLX and though there are similarities, they are not the same. The 4 transistors I removed are labeled NTE 270 and NTE 271. (2 of each. They are the center 4 of the 8 transistors and are indetified on the board as Q17, Q18, Q19, and Q20. The 4 remaining are Q8, Q9, Q10, and
Q11. What else should I check before I replace these 4 transistors? Should I swap the 4 remaining ones into the empty spaces and see what happens? I read on this site about constructing something with a 100w bulb but I have not found the actual post that explains it. I'm still looking. Thanks for any suggestions, recommendations, etc.
Tim
Q11. What else should I check before I replace these 4 transistors? Should I swap the 4 remaining ones into the empty spaces and see what happens? I read on this site about constructing something with a 100w bulb but I have not found the actual post that explains it. I'm still looking. Thanks for any suggestions, recommendations, etc.
Tim
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