Good day guys, I’m having some issues with output stability on this amp. It was brought to me in this condition power supply fully functional, output missing but I need to make some tests to see if driverboard is functional before I put the output mosfets back in the amp.
Previous tech says the output was burnt/shorted the replaced sets are overheating rapidly especially the rear four near the capacitor bank across from the output relays.
I’ve sent a pic of the amp board and driver board.
Previous tech says the output was burnt/shorted the replaced sets are overheating rapidly especially the rear four near the capacitor bank across from the output relays.
I’ve sent a pic of the amp board and driver board.
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Jumping?
Please (and this applies to anyone who needs repair help) use your sig line to list all equipment you have, editing it as equipment changes. Include the model numbers.
Top of page, menu USER CP >> EDIT SIGNATURE
Oscilloscope (yes or no)
Multimeter(s)
Type of signal source (grounded RCA shields preferred).
Soldering iron
Desoldering pump
Power supply
2 ohm current limiting resistor (hollow cylindrical ceramic 100w preferred)
Please (and this applies to anyone who needs repair help) use your sig line to list all equipment you have, editing it as equipment changes. Include the model numbers.
Top of page, menu USER CP >> EDIT SIGNATURE
Oscilloscope (yes or no)
Multimeter(s)
Type of signal source (grounded RCA shields preferred).
Soldering iron
Desoldering pump
Power supply
2 ohm current limiting resistor (hollow cylindrical ceramic 100w preferred)
Is there any first and foremost troubleshooting of the mainboard or audio driver board (power supply is working fine) that can be done before I install the output mosfets?
Re:Signature,
I have two workstation (home & work), so test environment may be different according to what and where I’m having problems with a particular device, all tools mentioned will never in the same area at any given time.
Re:Signature,
I have two workstation (home & work), so test environment may be different according to what and where I’m having problems with a particular device, all tools mentioned will never in the same area at any given time.
I'll assume that you checked all resistors and diodes in the audio output stage on the main board.
You can check the drive signals.
Are all of the outputs out of the board or is it only the U3 side?
You can check the drive signals.
Are all of the outputs out of the board or is it only the U3 side?
With proper drive signal after replacing the U1 along with the U3 and U4 the mosfets I’ve gotten 24N60 (original is 24N40) after I install four pieces one in each bank it’s over heating and drawing current from power supply, however when I remove and install the four original ones (some are defective hence I tried to buy a complete batch of new ones but only could get the N60 types) the four original ones work fine in the amp.
Is there any minor mods to get the heating ones to work (like decreasing gate resistance) or I should just try and get the original ones?
Is there any minor mods to get the heating ones to work (like decreasing gate resistance) or I should just try and get the original ones?
I understand but do you (or anyone here) know enough to re-engineer the output stage (which is very finicky)? If it fails with the re-engineered parts, do you cover the repair or do you make the owner pay for the second repair?
Make the owner pay for all costs for the right parts if he wants it repaired.
Make the owner pay for all costs for the right parts if he wants it repaired.