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    0-30 Vdc Stabilized Power Supply

    well, I've got some bad news :) I left supply 15mins with 15V and 2.85A and measured voltage drops for op amps and some components... pin 4 of U3 gets -0.02V :) R7 1.1V D6 2.4V D7 -1.1V and then something happened; Q2 started to smoke and I quickly turned off supply...it seems it is ok...
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    0-30 Vdc Stabilized Power Supply

    I replaced D7 and there is same thing! Nothing happened! I changed positions of U2 and U3 to see if one of them is burned but everything stayed the same! I checked voltages at U3 and they are all 0V except pin 6 (35V) and pin 7 (35.6V) What is the next element that I should look? Later I will...
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    0-30 Vdc Stabilized Power Supply

    well, you are wrong - LED is still working even without reg circutry And current pot isn't working! Is it possible that U3 is damaged? Neverthless, I ordered from TI free 5 samples of OPA445 :) I haven't tried putting Q1 back but i think it wont work because in the first place, reg circutry...
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    0-30 Vdc Stabilized Power Supply

    I forgot to tell you that you were right for R23 resistor! He is so damn hot!
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    0-30 Vdc Stabilized Power Supply

    Well yeah, it works at last ;D But current pot isn't doing nothing! No matter where I turn him, current stays the same! Voltage and current is cotrolled through voltage pot! And yes, they are properly connected, there is no problem with that... And what with Q1? Why isn't circuit working with...
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    0-30 Vdc Stabilized Power Supply

    I disconnected Q1 and it works! With Voltage pot I can change from 32 to 2.4V but there is more turning space and when I turn, voltage rises instantly to 35V! LED is always on, no matter where I turn Current pot I connected 50W 5Ohm resistor and then voltage drops to 22.9V max and minimum is...
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    0-30 Vdc Stabilized Power Supply

    My mistake for Q1! It has 0.6 drop at base, not at collector! So, U2 is dead now? I don't see any shorting and I checked it with multimeter buzzer! Will new one TL081 work? And my R14 is 1.5K; do I need to lower to 1.2 due to my trafo is only 24V? I've disconnected voltage regulators and...
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    0-30 Vdc Stabilized Power Supply

    Oh, I forgot to put links to PCB...here it goes...
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    0-30 Vdc Stabilized Power Supply

    Hi everyone! I've built this power supply but it doesn't work...at output it gives 0.2V all the time! Strange thing is when I disconnect power, voltage rises to 2.9V and then lowers to 0V! And U2 is SO DAMN HOT just after few seconds after powering up! I've been using some modified components...
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