Some amps will go into low voltage protect if there is any significant resistance in the B+ line. That needs to be eliminated as a possible problem. An inline fuse (about 15 amp) will protect the amp if the FETs are clamped to the heatsink.
This is a self-oscillating amp. There won't be a high-frequency carrier unless the amp is in good working order.
This is a self-oscillating amp. There won't be a high-frequency carrier unless the amp is in good working order.
Ok. I never used this principle. I know it exists. I used to design my own class D amp but has a clock generator outside the loop.
https://www.diyaudio.com/community/threads/scaling-down-karlsons.239729/#post-3572159
https://www.diyaudio.com/community/threads/scaling-down-karlsons.239729/#post-3572159
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I think that the LM311 is floating with the high-side source. If so, measure the DC voltage from pin 4 to pin 8. I'd expect it to be about 10v.
In the LM311M I have 9.58v, on the other hand the PS wave deformed again and generated noise, because of that I decided to investigate the fet471 and 260, I changed the 260 that came with Irfb42n20d replacing it with a similar one and the PS wave It returned to being rectangular and without noise, only for a moment, it returned to deform and make noise, now I have a doubt. Are the fets you mentioned correct? fet 471 is 75339P and fet260 is Irfb42n20d?
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The gates of the PS FETs doesn't have to have a square wave. This is a regulated supply so the waveforms won't be perfectly square. If you have the tutorial, look at the waveforms on the "MTX Power Supplies vs Other Amplifiers" page.
What relevance does D444 have?
What relevance does D444 have?
The waveforms on the output of the transformer won't be square unless the supply is struggling to maintain the target rail voltage. After target rail voltage is reached, the duty cycle will be reduced and the waveform will change shape.
Yes I have the tutorial but my CD is damaged and doesn't read, I kept several copies and unfortunately my wife deleted them from my 2 computers, that's why I haven't reviewed it
With a regulated supply, after the target rail voltage is met, you won't see a perfect square wave.
The noise on the input to the optocoupler is due to the reference. With an isolated scope (from the mains), place the negative scope clip on the terminal with no square wave and the tip of the probe on the terminal with the square wave.
The noise on the input to the optocoupler is due to the reference. With an isolated scope (from the mains), place the negative scope clip on the terminal with no square wave and the tip of the probe on the terminal with the square wave.
Thank you very much to the people who supported me. My amplifier finally works, I'm happy.
