Confirm that you have no pulse of DC on the input of either large output filter inductor on startup (when it goes into protect).
They're directly connected.
Can you (relatively) easily desolder one terminal of one of the inductors?
Can you (relatively) easily desolder one terminal of one of the inductors?
At the point on the board where you desoldered the winding, do you see the 80v pulse?
Do you see it on the other inductor?
Do you see it on the other inductor?
Yes on the board where I desoldered the inductor I get a pulse of DC of 110 volts now and it’s also present on the other inductor
Do you have a desk-lamp or something similar with a 110v incandescent (not LED, not CFL) bulb in it?
I want something to load the pulse to see if we can determine where it's coming from.
I want something to load the pulse to see if we can determine where it's coming from.
Connect one side of the plug to the speaker negative (likely directly connected to the main ground).
The other side will go to the points where you were checking for voltage.
Which point causes the light to light up?
The other side will go to the points where you were checking for voltage.
Which point causes the light to light up?
The outputs test good besides 1 bank
On the bank in question I get -98 volts on the gate and source and 110 volts on the drain
On the bank in question I get -98 volts on the gate and source and 110 volts on the drain
I’m getting the bulb to light up when I touch the tab of the 7812 regulator isn’t that suppose to be ground ?
I can also make it light up on the output leg of the 7812
And what are some areas you want me to check to see if I can get it to light up
I can also make it light up on the output leg of the 7812
And what are some areas you want me to check to see if I can get it to light up
The 7812 regulator ground may be on the negative rail.
At this point, I just want to know which half is driving the pulse. Touch the free wire of the bulb to the point where you desoldered the inductor.
The second point would be the other inductor.
At this point, I just want to know which half is driving the pulse. Touch the free wire of the bulb to the point where you desoldered the inductor.
The second point would be the other inductor.
I was touching the first spot where I unsoldered the inductor and it blew the outputs and blew the driver ic .
Once I replace these again I’ll get back to you
Once I replace these again I’ll get back to you
Back to this amp .
You were right about the gate resistors for the outputs .
I didn’t notice it before but someone put in the wrong value .
Also the 100k resistors were not the right value as someone replaced them with a much lower value .
Since the values were wrong could this have caused the voltage I was seeing on the inductor when powering up ?
You were right about the gate resistors for the outputs .
I didn’t notice it before but someone put in the wrong value .
Also the 100k resistors were not the right value as someone replaced them with a much lower value .
Since the values were wrong could this have caused the voltage I was seeing on the inductor when powering up ?
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