I have this amplifier in the workbench, the flashing protection LED flashes and that intermittent sound is heard in the horn without inserting the RCA, when the signal is connected the amplifier sounds however I want to determine where the damage comes from if someone has been found An equal problem I read your comments about it.
Regards
Regards
Thanks Crazylogix I have been reading the forums and I have found valuable information for now I am focused on correcting the heating of the mosfet from the source on one side and I have some references of voltages I checked the gate resistors the voltage in the gate of those that heat up It is 6.78 and those that do not heat up are 6.70. Now at night I check the drive semiconductors and the driver card of the mosfet. I keep reading.
Regards
Regards
Good morning Perry, attached images of the waveforms on both sides of the source before and after the resistance, the voltage of the mosfet only varies slightly from the side that is not heated by taking the black tip of the source of the Fet and the positive from the gate I have 6.72 and on the side that heats up I have 6.80, I tested the drive transistors on that side and they measure well. Will it be the transformer?
Generally, if a transformer is defective, it's either passing 12v to the secondary or it's causing very high current draw. From your posts, yours is doing neither. That doesn't mean that a bad transformer is out of the question but it's unlikely.
That first waveform looks like it may have a defective/weak PNP driver.
That first waveform looks like it may have a defective/weak PNP driver.
Hi Perry I changed the PNP transistors everything was normal, after a while it started to increase the current consumption and failed lm317t I took it out and low consumption
source-side transistors still heat up but less than before. It is normal for them to warm up a little or there is still something else that I should check I have noticed that the consumption increases and falls but is not greater than 1.90 amp or less than 1.25 amp without lm317 without rectifiers
source-side transistors still heat up but less than before. It is normal for them to warm up a little or there is still something else that I should check I have noticed that the consumption increases and falls but is not greater than 1.90 amp or less than 1.25 amp without lm317 without rectifiers
Understand that heating has a LOT of variables. I've never documented the temperature rise for the PS FETs in this amp (or any other). I don't think you can expect them to remain precisely at room temperature.
The removal of the LM317 is likely disabling the entire output stage which is why the current draw is less.
In my notes, I have significantly higher idle current draw than you have.
The removal of the LM317 is likely disabling the entire output stage which is why the current draw is less.
In my notes, I have significantly higher idle current draw than you have.
Ok Perry I understand, I was just wondering why on one side it stays colder than the other comparing one side of the fountain with the other of course, but well I will go for the LM317 which is defective I will put the rectifiers and continue with the repair based on what I have read so far in the forum of other colleagues. I will consult any questions
The translations aren't clear enough for me to understand precisely what you're asking.
If only one bank of FETs in the PS is heating, that's a problem. If the two banks for one transformer are heating equally, that likely means that that transformer is doing more work. In this amp, one transformer only supplies power to the output FETs. The other transformer supplies to the outputs AND all of the low-voltage circuits.
If you have the rectifiers out, confirm that all output drive signals are good before you reinstall them.
If only one bank of FETs in the PS is heating, that's a problem. If the two banks for one transformer are heating equally, that likely means that that transformer is doing more work. In this amp, one transformer only supplies power to the output FETs. The other transformer supplies to the outputs AND all of the low-voltage circuits.
If you have the rectifiers out, confirm that all output drive signals are good before you reinstall them.
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