I have a PMP5000 that I had to resurect. I had to trace out the power supply to repair it.
I can give you hint: First, a small supply runs directely from the line and generates some of the small voltages. While this starts, the main power caps are charged through limiting resistors. The main switcher is brought online and if the power amps acheive balance, then a relay connects the speakers and shorts the limiting resistors.
This is what is in the 5000 and I suspect the 3000 is similar.
In my 5000, there was arcing at one side of the power amps. The board was burned and three power fets fried. Cancer of burned board had to be carved out and traces replaced by hardwiring. In addition, the limiting resistors were blown open, both main switching transistors were blown and 4 small driver transistors (surface mounted) and several diodes AND a switching regulator chip (surface mounted).all fried/
Hint: When restarting the unit, put a 150 watt light in series with one of side of the power input to limit the current in case you did not get all the dead bodies out.
This is a class "D" amp which drives PCM waves into a filter which is then the audio output. It is much more efficient thaan a linear amp.
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I have a PMP5000 that I had to resurect. I had to trace out the power supply to repair it.
I can give you hint: First, a small supply runs directely from the line and generates some of the small voltages. While this starts, the main power caps are charged through limiting resistors. The main switcher is brought online and if the power amps acheive balance, then a relay connects the speakers and shorts the limiting resistors.
This is what is in the 5000 and I suspect the 3000 is similar.
In my 5000, there was arcing at one side of the power amps. The board was burned and three power fets fried. Cancer of burned board had to be carved out and traces replaced by hardwiring.
In addition, the limiting resistors were blown open, both main switching transistors were blown and 4 small driver transistors (surface mounted) and several diodes AND a switching regulator chip (surface mounted).all fried/
Hint: When restarting the unit, put a 150 watt light in series with one of side of the power input to limit the current in case you did not get all the dead bodies out.
This is a class "D" amp which drives PCM waves into a filter which is then the audio output. It is much more efficient thaan a linear amp.