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fikic's Achievements


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  1. Somewhere in this topic, somebody said, that some capacitor must be changed from electrolytic to tantal or something. Try to browse a little.
  2. So, I need at least 28V 120VA transformer? But output with 28V or 30V transformer has also hum at maximum output voltage, yes?
  3. With this hum, you mean just noise, or it has impact on quality of output?
  4. My transformer is 250VA, so current isn't the problem. So 24V output is just fine?
  5. No, I have 3A version with 24V AC toroid transformer.
  6. I changed output transistors and it works. I get maximum 24V on output. Is this ok?
  7. 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).
  8. 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?
  9. 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 is not the case. So, what should I check next. What could happen in that case, when you swap - and AC of rectifier. PS.: PSU worked perfect before that.
  10. audioguru says, that he doesn't use Eagle..so I doubt that it is his..
  11. 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..
  12. 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..
  13. @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. :-*
  14. PCB is not Eagle, it's Kicad..I will send you pdf..
  15. 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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