Hey I'm repairing this amp and the yellow light stays on and the blue light flashes. I think it's the power supply I replaced all mosfets and still same.. the powersupply chip clicks ..any ideas... waiting on my occyliscope but do these amps have any known issues? Thanks I'm new to complicated amp repair so work with me.. my amps I've repaired in the past usually just need fets replaced and good to go but this is an expensive amp and I ordered all the mosfets over 100$ worth and that wasnt the issue...thanks
Testing FETs will tell you essentially 100% whether FETs are good or bad without replacing them.
Desolder and lift the center terminal of the rectifiers. Does the supply power up.
Desolder and lift the center terminal of the rectifiers. Does the supply power up.
Ok I found the th1002 isn't there unless it's somehow built into the board.i tried getting a reading with the ohm meter I'll look at other pics of amp to see if mines missing..its gonna be a pita to solder it its in between one of the transformers ugh..I replaced all transisters they are good..
In the photos I have TH1002 isn't installed.
Does the power supply run continuously with the rectifiers out of the circuit? You didn't need to remove them. All you needed to do is desolder and lift the center terminal.
Does the power supply run continuously with the rectifiers out of the circuit? You didn't need to remove them. All you needed to do is desolder and lift the center terminal.
It's just the protect ..wierd colors for some reason I would think yellow would be thermal... the way my brains wired.lol
If you get this before you get the scope, measure the DC voltage across the gate and source legs of the PS FETs. What voltage do you read.
Do you know how to use a scope?
Do you know how to use a scope?
I have fiddled with them in the past I believe I hnow how to dial and zoom in and find a sine wave I might have to tinker with this specific scope cuz it's not digital it's an 2 channel analog I ran a digital single channel and a single channel old raycothode tube type oldschool scope not too long ago... I will read voltages ...actually my power supply in is 12v 4abut the fets on ps are 7.8v I beileve
And i think 7.6v on other set or its the voltages between the drain and source.ill double check I can't quite remember.. thanks
Make/model scope?
I need definitive numbers when you post voltages. When you measure the voltage on or across a component, you need to post the voltage or resistance, also post the circuit board designation of the component.
I need definitive numbers when you post voltages. When you measure the voltage on or across a component, you need to post the voltage or resistance, also post the circuit board designation of the component.
Ok got the scope ..it's a hitachi v212 20 mhz... and the gate to source voltage is 11.78 q1 to q6. 12.3v q1000 to q1005. Sorry..about that..this is an older scope will it work its pretty 🦕
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One thing I don't have is the ground clip for the scope probe. will any alligator clip work if it fits in touches the piece of metal in the probe?
Are those voltages with the black probe on the source terminal and the red on the gate terminal?
Connect the ground lug on the front of the scope to the ground terminal of the 12v power supply that you're using to power the amp. That's all you will need for a ground for most signals.
Connect the ground lug on the front of the scope to the ground terminal of the 12v power supply that you're using to power the amp. That's all you will need for a ground for most signals.
Ok messing with thus scope is a real pita so I'd rather use a little 2 channel newer style but this is all I have for now just let me know what and where I need to measure and if you work with me at the end of this I'll shoot you some donation for you being patient man I am really appreciative of your time. I'm a quick learner and I will catch on quick I promise.
So I guess there is 0 volts between the source right-side and gate left side of either ps transisters
I'd prefer to use that scope than virtually any of the newer LCD scopes. It will give a cleaner display of the waveform and that's why I use a scope.
What do you mean by:
So I guess there is 0 volts between the source right-side and gate left side of either ps transisters
Read the following page but pay special attention to the area in white.
http://www.bcae1.com/oscope.htm
What do you mean by:
So I guess there is 0 volts between the source right-side and gate left side of either ps transisters
Read the following page but pay special attention to the area in white.
http://www.bcae1.com/oscope.htm
So 7 was a guess it was the 7 out of the 11.78.. but that's not the right voltages I get zero volts between source and gate on all ps fets