How much AC is on the rails? a few volts or a few millivolts?
Do you have the DC that you expect when the PSU is not connected to the amp? describe your psu - CRC? how much C and R?
What is your expected rail voltage?
What voltage do you get over R23 and R25? If less than ~4V you won't turn on Q2/Q11 and their drains will be close to the positve rail.
Do you have the DC that you expect when the PSU is not connected to the amp? describe your psu - CRC? how much C and R?
What is your expected rail voltage?
What voltage do you get over R23 and R25? If less than ~4V you won't turn on Q2/Q11 and their drains will be close to the positve rail.
Several volts AC.
I have 18VDC as expected. I'm using this power supply: http://www.kk-pcb.com/power-x.html
As I´m using this board http://www.kk-pcb.com/alephx.html I have to come back tomorrow for the voltage over R23 and R 25
I have 18VDC as expected. I'm using this power supply: http://www.kk-pcb.com/power-x.html
As I´m using this board http://www.kk-pcb.com/alephx.html I have to come back tomorrow for the voltage over R23 and R 25
If you're getting that much AC then something is seriously wrong. Something is drawing a ton of current, you should be seeing millivolts with that filter. check for a solder bridge to ground or across the rails, backwards electrolytic or backwards FET.
The part numbering I was using refers to Grey's schematic. R23/25 are the 390R in the legs of teh LTP.
The part numbering I was using refers to Grey's schematic. R23/25 are the 390R in the legs of teh LTP.
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