All of my notes are for the rev 10 regarding this test. I'm not 100% sure it works with rev 3 they are very similar but not precisely the same circuits.
Earlier, you had an op-amp that wasn't following, as it should. That could have been the entire problem. Remove the 1/2 jumper and see if you can get the output to go to 50% (or from 0% to 100%) by using both the DC pot and the clipping pot.
Earlier, you had an op-amp that wasn't following, as it should. That could have been the entire problem. Remove the 1/2 jumper and see if you can get the output to go to 50% (or from 0% to 100%) by using both the DC pot and the clipping pot.
It for sure seems to be working better.
Without the solder bridge, it comes up and keeps switching before it stopped after 100ms.
Maybe this is a Rev 3 difference, but it seems to sweep back and forth in the duty cycle during the 15 seconds now that I have removed the bridge. Should I let it start on the power side? I do still have D600 off. To see if gets stable to adjust the pot.
Without the solder bridge, it comes up and keeps switching before it stopped after 100ms.
Maybe this is a Rev 3 difference, but it seems to sweep back and forth in the duty cycle during the 15 seconds now that I have removed the bridge. Should I let it start on the power side? I do still have D600 off. To see if gets stable to adjust the pot.
You can install the outputs and check the drive signal at the gates of the output transistors. Without rail voltage, the outputs are in no danger of being damaged.
Sorry for the delay in responding. I want to leave this note for anyone who might look at this later.
I would like to note that in this REV 3, the best I could get out of this was a 30% duty cycle with the source /drain of Q506/505 jumpered. Once I reinstalled the 4 output fets and d600(the rectifier), I was able to achieve normal behavior(50% duty).
My problems were shorted power section mosfets, gate resistors, 1 shorted output fet, U513 Op amp shorted rail high, and in the process of repair, J4 became intermittent.
The power supply mosfets showed as visibly burnt.
Output fet showed by testing with a multimeter under the assumption one of them was the primary failure.
U513 was found by jumping Pin 1/2, making it into a voltage follower of Pin 3. The voltage didn't follow, proving it to be defective.
J4 caused the symptom of no housekeeping voltage.
Hopefully, this summary helps! Thank you Perry!
I would like to note that in this REV 3, the best I could get out of this was a 30% duty cycle with the source /drain of Q506/505 jumpered. Once I reinstalled the 4 output fets and d600(the rectifier), I was able to achieve normal behavior(50% duty).
My problems were shorted power section mosfets, gate resistors, 1 shorted output fet, U513 Op amp shorted rail high, and in the process of repair, J4 became intermittent.
The power supply mosfets showed as visibly burnt.
Output fet showed by testing with a multimeter under the assumption one of them was the primary failure.
U513 was found by jumping Pin 1/2, making it into a voltage follower of Pin 3. The voltage didn't follow, proving it to be defective.
J4 caused the symptom of no housekeeping voltage.
Hopefully, this summary helps! Thank you Perry!
