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    0-30V Stabilized Power Supply

    Thank you audioguru, I am closer now. I figured out, that I turned Q3 backwards. But still, it doesn't work perfect. At current adjustment pot turned to lowest value, LED is not on. It turns on somewhere on the end of turn of current adjustment pot. Voltage of pin 6 is 28V, when LED is not on...
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    0-30V Stabilized Power Supply

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    0-30V Stabilized Power Supply

    All this I wrote applies to the case, when I have no load on output...
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    0-30V Stabilized Power Supply

    I made a mistake when I was drawing schematic. I didn't connect - of C1 to gnd. I corrected PCB now, and PSU works when I connect a load. But only in some cases, when I turn pot for current regulation, the voltage drops. LED is still on the whole time. Now the voltage on output of U3 is 24V but...
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    0-30V Stabilized Power Supply

    Yes, it has and if I connect a load on it the voltage drops unnormally and there is no power. What could it be?
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    0-30V Stabilized Power Supply

    The voltage on U2 output raises and falls like output voltage if I turn current adjustment pot. The lowest voltage on outpu of U2 is 17V, the highest is 35V (I was meassuring pins 6 and 4??)..
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    0-30V Stabilized Power Supply

    No, that's just on my schematic becouse of Kicad (doesn't have BZX85), but actually, I used BZX85C. What could be the reason also? Why is voltage changing when I turn current adjustment pot? I double checked PCB and it's completely short connection free. It's soldered good and everything is...
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    0-30V Stabilized Power Supply

    This is exactly the one I built. So, audioguru, can you answer me, what can I do about my issues to solve them. I also noticed, that PSU has no power. If I connect a load on it, the voltage drops unnormaly.
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    0-30V Stabilized Power Supply

    I think, there is no problem with this schematic and PCB.. @audioguru, C8 isn't shorted.. sch.pdf pcb.pdf
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    0-30V Stabilized Power Supply

    I've noticed something new: If I have pot for voltage adjustment set to maximum value and I am changing current limit pot value from minimum to maximum, something strange happens. At it's minimum, output voltage is 40.5V. Then I am slowly raising it. The output voltage stays 40.5V for about 1/4...
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    0-30V Stabilized Power Supply

    You've disunderstood me. I am also adjusting voltage with P1 and current with P2, but with RV2 I can set the maximum output voltage. I used schematic that you posted it one page back. PS.: I still don't know, why LED is always on. What is the reason, what can I do?
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    0-30V Stabilized Power Supply

    The newest version with mc34071 opamps.
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    0-30V Stabilized Power Supply

    I built it (3A version) and I have a few issues: - current limiting LED is always on (if I turn current pot to max value it even lights more) - I just can adjust minimum voltage to 50mV with voltage trimmer - what can I adjust with other two trimmers? However, PSU woks fine, the maximum output...
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    0-30V Stabilized Power Supply

    Nice PCB you have there. But mine is made just for 3A version, so I think the thickness of output tracks is good. Here is final version: pcb.pdf
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    0-30V Stabilized Power Supply

    Here it is: pcb.pdf
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    0-30V Stabilized Power Supply

    This is becouse of .pdf file. When I print it it's ok. I am working on strenghtening pads.
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    0-30V Stabilized Power Supply

    If you have Kicad, you can try mod my verison to 5A. I can try it too, but not this week.
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    0-30V Stabilized Power Supply

    Ok, I re-drawn my PCB, so it's jumper-free. I also strengthened all tracks, so this is my final version I guess. I will try it once this week and I will report. dokumentacija.zip
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    0-30V Stabilized Power Supply

    I am planning to use 24V/250VA transformer for this project, since this is the only one I have now. Is this ok? What is the difference if I use 10000uF instead of 12000uF for C1 (for 3A design)? Has anyone tryed to draw single-sided PCB for new 3A project? PS: I drew PCB in Ki-cad. Can someone...
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    0-30V Stabilized Power Supply

    I am working on this. I completed .sch file in eagle and now I am working on PCB project. When I am finished, I will publish it here.
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