Hello, I'm working on a linear power 2502iq.
It had audio section burned, transistor, emitter resistor, drivers, muting transistor.
Now all is new, amp works but one side has 40mv DC offset, other side has 500mv DC offset.
I tried to reverse all the small transistor but result is the same, 500mv offset in the same side.
It had audio section burned, transistor, emitter resistor, drivers, muting transistor.
Now all is new, amp works but one side has 40mv DC offset, other side has 500mv DC offset.
I tried to reverse all the small transistor but result is the same, 500mv offset in the same side.
Are there any op-amps in the preamp section?
In most feedback circuits, there is an electrolytic capacitor that is in the voltage divider, in the branch that goes to the audio ground. This prevents the amplifier from amplifying DC (which would increase offset). If that capacitor is leaking electrically, the offset could be higher than normal.
In most feedback circuits, there is an electrolytic capacitor that is in the voltage divider, in the branch that goes to the audio ground. This prevents the amplifier from amplifying DC (which would increase offset). If that capacitor is leaking electrically, the offset could be higher than normal.
There is 1 opamp but opamp is ok, capacitors are all new, I changed all the electrolitic caps and checked poliester caps when I see this problem.
Can i use mpsa56 to replace all the mps8599?
I see that 1 mps8599 is leaking, when I reverse its the good channel has 120mv DC offset than 40 with other mps8599.
The damaged channel has 500mv every time.
Can i use mpsa56 to replace all the mps8599?
I see that 1 mps8599 is leaking, when I reverse its the good channel has 120mv DC offset than 40 with other mps8599.
The damaged channel has 500mv every time.
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Problem seems solved.
I removed and checked all the passive components in the audio section without finding anything out of tolerance.
I reassembled and re-sold everything and now the amplifier works well, the 500mv dc offset has gone.
now I have a 30mv dc offset in one channel and 70mv dc offset in the other, but the problem is 6 mps8599 transistors (3 for each channel)
if I invert the transistors the offset moves to the other channel, I have to find some mpsa56 or something equivalent to replace them
I removed and checked all the passive components in the audio section without finding anything out of tolerance.
I reassembled and re-sold everything and now the amplifier works well, the 500mv dc offset has gone.
now I have a 30mv dc offset in one channel and 70mv dc offset in the other, but the problem is 6 mps8599 transistors (3 for each channel)
if I invert the transistors the offset moves to the other channel, I have to find some mpsa56 or something equivalent to replace them
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before I had an offset of 500mv dc in a channel, after removing and replacing all the passive components that offset is gone.
I had tried to invert all the semiconductors but an offset of 500mv remained on the same channel
my problem was those 500mv dc always on that channel that disappeared after removing and re-welding all the passive components
I had tried to invert all the semiconductors but an offset of 500mv remained on the same channel
my problem was those 500mv dc always on that channel that disappeared after removing and re-welding all the passive components
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