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    0-30 Vdc Stabilized Power Supply

    Somewhere in this topic, somebody said, that some capacitor must be changed from electrolytic to tantal or something. Try to browse a little.
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    0-30 Vdc Stabilized Power Supply

    So, I need at least 28V 120VA transformer? But output with 28V or 30V transformer has also hum at maximum output voltage, yes?
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    0-30 Vdc Stabilized Power Supply

    With this hum, you mean just noise, or it has impact on quality of output?
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    0-30 Vdc Stabilized Power Supply

    My transformer is 250VA, so current isn't the problem. So 24V output is just fine?
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    0-30 Vdc Stabilized Power Supply

    No, I have 3A version with 24V AC toroid transformer.
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    0-30 Vdc Stabilized Power Supply

    I changed output transistors and it works. I get maximum 24V on output. Is this ok?
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    0-30 Vdc Stabilized Power Supply

    Ok, so Ohm-meter must show nothing between collector and emmitter of 2n3055, becouse it's infinite resistance? Mine show something between 100 and 200 kOhm (on both of them, on one even less).
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    0-30 Vdc Stabilized Power Supply

    I replaced BD139 with BD135, becouse I don't have any BD139 left. Is this ok? How can I check 2N3055 transistors - I don't have transistor tester. Should one conduct between base and emmiter and between collector and emittor? If not, where it should?
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    0-30 Vdc Stabilized Power Supply

    Hy guys. I've made a little mistake, when I connected a diode bridge. I accidentally swapped - and AC connector. I then saw some smoke and litle bang. On the output of psu, I now only get constant 33V and I can't regulate it. I thought, that opamps may be the reason and I replaced them, but this...
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    0-30V Stabilized Power Supply

    audioguru says, that he doesn't use Eagle..so I doubt that it is his..
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    0-30V Stabilized Power Supply

    Your PCB is very negligent drawn.. Don't use autorouter, where you can draw PCB on your own. This one is really easy, especially if you have double-sided board like you..Just for an advice, your PCB could be much smaller for double-sided board, and much more accurate..
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    0-30V Stabilized Power Supply

    It is normal..when the LED is on, your output voltage on PSU should drop. But try it with a bulb or something that has a constant current consumption..
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    0-30V Stabilized Power Supply

    @audioguru, thank you for all of your help. I replaced D5 and D6 and PSU works perfect! Current regulation works and everything is fine! Thank you hundred times for your help. :-*
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    0-30V Stabilized Power Supply

    PCB is not Eagle, it's Kicad..I will send you pdf..
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    0-30V Stabilized Power Supply

    Ok, I replaced D7 (two diodes) and it doesn't make any difference, so this is not the case. Diodes are fine. Voltage drop across both of them is just about 400mV.  ??? Can you pleeeeease take a look at my schematic and PCB, becouse I don't see any mistake now..please.. dokumentacija.zip
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    0-30V Stabilized Power Supply

    Please look at my post again, I edited it and you replied faster..
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    0-30V Stabilized Power Supply

    audioguru, I mounted transistors on heatsink and tryed PSU. I shorted its output and measure current. At voltage set to 30V and current regulation pot set to highest value, I calibrated it to max current 3A. But when I get near the minimum setting of current adjustment pot, it took about 5-10A...
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    0-30V Stabilized Power Supply

    You didn't understand me. At P2 minimum pin 2 of U3 is 45.5mV, at its maximum pin 2 of U3 is 95.5mV. Anyway, Too high...
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    0-30V Stabilized Power Supply

    The voltage drop across R7 is just 5mV. 95mV voltage drop is just on pin 2 of U3.
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    0-30V Stabilized Power Supply

    P2 is connected ok. When P2 is at it's minimum, the voltage on pin 3 of U3 is 15.05mV, at it's maximum it's 2.07V. Is that normal? At P2 minimum, the voltage on pin 2 of U3 is 45.5mV, at it's maximum is 95.5mV. So there is voltage drop on R7 in any case. Why is that? PS.: Is normal, that when I...
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