Replaced them and the drive signal looks like this on all of the fets .
Scope set to 5us 5volts/div
Amp still draws excessive current
Scope set to 5us 5volts/div
Amp still draws excessive current
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If the trace on your scope is that blurry, try to clean it up with the focus control. If that doesn't get it sharp, using the astig AND focus (adjust one then the other) should do it.
I don't see anything wrong with that signal.
Does the higher current draw come only after the outputs start oscillating?
Did you find the astig control on your scope?
Does the higher current draw come only after the outputs start oscillating?
Did you find the astig control on your scope?
No didn’t find that setting on my scope .
Can I pull the rectifiers and see if the problem is in the power supply or output section ?
Can I pull the rectifiers and see if the problem is in the power supply or output section ?
The oscillation should be delayed. just look for the timing of the high current draw vs the oscillation.
It could be normal.
Did you look up the manual for your scope? Did you look on the sides and back of your scope for something marked astig. If you're not interested, I'll drop the subject.
It could be normal.
Did you look up the manual for your scope? Did you look on the sides and back of your scope for something marked astig. If you're not interested, I'll drop the subject.
When trying to power the amp up it draws 60 amps of current .
So i’m wondering if I can isolate it to see if it the power supply or output section .
I checked the front back and sides and there is no adjustment for that.
I will see if I can find a model number on the ship somewhere since there’s no make or model number anywhere on it
So i’m wondering if I can isolate it to see if it the power supply or output section .
I checked the front back and sides and there is no adjustment for that.
I will see if I can find a model number on the ship somewhere since there’s no make or model number anywhere on it
Ok I see the problem it blew 3 out of the 4 outputs in 1 bank .
I removed them and amp powers up .
Are the drivers for the outputs on the main board or on the card do you know by chance ?
I removed them and amp powers up .
Are the drivers for the outputs on the main board or on the card do you know by chance ?
So the drivers for the outputs are 2g and W1G?
So a mmbta56,06 ?
Never seen one marked W1G
Or are they the U2000 and U2002 the ic’s?
So a mmbta56,06 ?
Never seen one marked W1G
Or are they the U2000 and U2002 the ic’s?
The transistors around the driver transformers are the driver transistors. You must check all of them, the diodes and resistors.
The ICs drive the transformers. The driver ICs and transformers sometimes fail as well.
The ICs drive the transformers. The driver ICs and transformers sometimes fail as well.
All the diodes resistors and transistors check good
How do I tell if the ic has failed ?
I get totally different voltages on both ic’s
How do I tell if the ic has failed ?
I get totally different voltages on both ic’s
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Here are the voltages I get on the ic’s
U2000
Pin 1:0.80
Pin 2:3.09
Pin 3:0.00
Pin 4:3.09
Pin 5:5.14
Pin 6:8.15
Pin 7:3.68
Pin 8:7.06
U2002
Pin 1:0.69
Pin 2:0.39
Pin 3:0.00
Pin 4:0.38
Pin 5:0.00
Pin 6:8.10
Pin 7:0.00
Pin 8:7.06
U2000
Pin 1:0.80
Pin 2:3.09
Pin 3:0.00
Pin 4:3.09
Pin 5:5.14
Pin 6:8.15
Pin 7:3.68
Pin 8:7.06
U2002
Pin 1:0.69
Pin 2:0.39
Pin 3:0.00
Pin 4:0.38
Pin 5:0.00
Pin 6:8.10
Pin 7:0.00
Pin 8:7.06
After removing the shorted outputs all I get it a quick tik Throughbthebyest speaker so I believe the amp will work if I add all of the outputs .
If I add any outputs on that bank they get hot fast
If I add any outputs on that bank they get hot fast
I’m gonna guess it’s a driver transistor that’s bad .
I replace the outputs in that bank and the amp plays clean audio .
It just the outputs in that bank get hot within 30 secs
I replace the outputs in that bank and the amp plays clean audio .
It just the outputs in that bank get hot within 30 secs