I found some weird piece or thing that seems to be fragile .. texteure looks like something maybe between mica and paper its weird and i found it underneath the PCB when i was turning it around.. maybe its not related to the amp but i tought i should tell you... i case one of you recognize the piece and where it could come from...
The gates seem fine 24.9 ohms is the resistance of them so looks like they are still within tolerance. The gate to source should not read OL. You have a problem somewhere. Perry has helped me with 3 BD1500 amps and none of them have read OL from gate to source in resistance, or your meter does not have the right range setting.
You did check the fets before soldering them to the MESHA board after tinning them to see if one or more was leaky correct??
You did check the fets before soldering them to the MESHA board after tinning them to see if one or more was leaky correct??
I checked all of them with the DMM in the 200ohm range before and after soldering them and none of them were short.. same reading as now!!!
its not showing OL on my meter its simply showing nothing like when the probes doesnt touch.. and to verify that the probes work i touched them.. and it shows 1ohm so they are ok
its not showing OL on my meter its simply showing nothing like when the probes doesnt touch.. and to verify that the probes work i touched them.. and it shows 1ohm so they are ok
all of the output FETs
i dont know wich would be the "problem side"
i wanted to ask Perry if i could lets say.. plug only the HV- side and see if it pulls 20A
and same thing with the HV+ side..* to isolate the problem, but i dont know if this could cause some problems...
I dont want to blow some FETs.. they are all non leaking now... i would like to keep them good to go
i dont know wich would be the "problem side"
i wanted to ask Perry if i could lets say.. plug only the HV- side and see if it pulls 20A
and same thing with the HV+ side..* to isolate the problem, but i dont know if this could cause some problems...
I dont want to blow some FETs.. they are all non leaking now... i would like to keep them good to go
looks like there is somekind of isolation between the aluminium bar and the tabs.. i have checked them and they are all (outputs and power) NON shorted to the heatsink... this would really have made sense since its pulling so much.. i tought it was it and that it was that stupid but no... they are not shorted!!!
for the op-amps.. could you be more specific?
they are many LM*** and the mic4420ct wich one do you want me to check ?
but no... they are not shorted!!!for the op-amps.. could you be more specific?
they are many LM*** and the mic4420ct wich one do you want me to check ?
Are you 100% sure that there are no solder bridges on the board anywhere?
The red and black wires feed a very limited number of components (outputs, rail caps...). If the rail caps are not shorted and the outputs are not shorted, there isn't much else. The drive circuit can't easily cause excessive current draw.
The red and black wires feed a very limited number of components (outputs, rail caps...). If the rail caps are not shorted and the outputs are not shorted, there isn't much else. The drive circuit can't easily cause excessive current draw.
yes Perry
I have checked all of the output FETs legs to see if they are shorted... negative
if the output FETs tabs are shorted to the heatsink... negative
i even measure the black and red wires to see if they read shorted.. negative...
I know something BIG must be connected together to pull that much.. but i cant see anything suspicious
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