I remember ... yesterday, checking voltages at different points, there was only high voltage, in a group of eight MOSFET (the 3415), in the other group, there was no high voltage (the 6215) this may be significant?
Anyway, this afternoon will send voltage U17 (now I'm at work)
Perry is being a great help for this repair.
Anyway, this afternoon will send voltage U17 (now I'm at work)
Perry is being a great help for this repair.
I ... I think I've had bad luck again ...
I'll divide this post into two parts: before the explosion and after the explosion.
prior to the explosion:
I replaced U7, and new tensions that gave me were:
Pin 1: 0
Pin 2: 0.035
Pin 3: 0.035
pin 4: -9.89
pin 5: 0
pin 6: 5.86
pin 7: 9.89
pin 8: 0
Do these tensions were correct, or there was still something wrong?
When connecting the speaker produced a bit of pink noise (sssshhhhs and 0.5 V at the terminals) but I had to remove it soon, because I saw some smoke out around R180 or R181 (not sure, but next came there )
I disconnected the speaker and I started to check voltages, for example, I saw that tensions had risen U5 (pin 2: -5.09 and pin 6: 8.26) also in U17 (pin 6: -5.75)
The explosion:
When I was checking U8 (pin 2: 5.77) and touching the pin 3, not sure if I have a short between pin2 and pin 3 with the probe (I have inspected the probe and the IC pins and no trace of the spark), the case is, who have exploited Q12 and Q109 (see picture of how they have been)
Do not know what could have happened, I unsoldered the group of eight mosfet, and found six in short, in its three terminals!
What do you think Perry?
I'll start from scratch, and I will order more parts ...
Again, I again thank you for your help, Perry
The day I get repair this amp, I'll open a bottle of champagne ...
I'll divide this post into two parts: before the explosion and after the explosion.
prior to the explosion:
I replaced U7, and new tensions that gave me were:
Pin 1: 0
Pin 2: 0.035
Pin 3: 0.035
pin 4: -9.89
pin 5: 0
pin 6: 5.86
pin 7: 9.89
pin 8: 0
Do these tensions were correct, or there was still something wrong?
When connecting the speaker produced a bit of pink noise (sssshhhhs and 0.5 V at the terminals) but I had to remove it soon, because I saw some smoke out around R180 or R181 (not sure, but next came there )
I disconnected the speaker and I started to check voltages, for example, I saw that tensions had risen U5 (pin 2: -5.09 and pin 6: 8.26) also in U17 (pin 6: -5.75)
The explosion:
When I was checking U8 (pin 2: 5.77) and touching the pin 3, not sure if I have a short between pin2 and pin 3 with the probe (I have inspected the probe and the IC pins and no trace of the spark), the case is, who have exploited Q12 and Q109 (see picture of how they have been)
Do not know what could have happened, I unsoldered the group of eight mosfet, and found six in short, in its three terminals!
What do you think Perry?
I'll start from scratch, and I will order more parts ...
Again, I again thank you for your help, Perry
The day I get repair this amp, I'll open a bottle of champagne ...
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