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Everything posted by MonSSter

  1. r2 is 82ohms, also nothing is shorted ... maybe this will help .. c3 voltage is also 0, and c2 is 17.7V(but as you said, there's AC not DC )
  2. i replace d5 and d6, and nothing ... i measure as you said and i got the same measurement's ... that's d5 has 0v, r3, d7 has around 0,7v ... so i realy don't know now :( ... you think i should start all over again?
  3. well replacing D7 did nothing new ... so i measure the voltage on r2 where there is 17.7V, and on D5 there's 0V(?!) ... any ideas?
  4. ok i belive that diodes are dead or something, because on d7, theres 0.7V .. so i will replace them during the weak and then report again .. tnx!
  5. ..and what are the parts for negative voltage?
  6. r13 has ~34V ... and r14 has 0.8-0.9V ...
  7. Hi! exams are over, so i can finish the power supply now ... i think i located the problem and that is the voltage on q1, collector is 0.8~0.9V so i'm asking if that could be the problem( i have no output )
  8. well . . the output voltage of u2 is the same as before thats .. around 200mV and he's still very hot. The u2 is tl081
  9. hmm .. I replaced q4 and u2(q2 looks ok)disconeted the r15 but nothing happend... output was i bit higer that's all ... so the thing still doesn't work :D ... any new directions(maybe you draw me the solution :)). Tnx eemmm ... q4 C = 34V, E = 0,5V B = 0,5V
  10. helow! it's me again :) .. well i replace the Q2 and the u2(new one is still heating like mad) and now the output voltage is ~0.4V .. the voltage in q4 E,C and B is 32V+ ... so what is wrong now?
  11. ok .. will go and replace these componets and then report :) .. thx
  12. well ... i changed the orientation of the Q2( so that the emitor is pointing towards 8th pin( the base of Q4 ) ) and now the situation is following ... output voltage is 0.5V, u2 is still heating like mad ;), the voltage on Q2 collector is ~34V ... Q4 base volt. = 0,5V collector volt. = 34V Q3 emmiter volt. = 34V U2 output = ~200mV any directions?
  13. i do use 24 transformer. the 6pin on U2 shows ... 0V, and the Q2 shows 34V ... so you think that Q2 is destroyed?
  14. Hi! I just builded your power supply but i doesn't work ;) ... at output it always shows ~34V and i can't regulate it with P1 ... U2 is heating like mad... i checked and rechecked the PCB and will do it again :) ... voltage on C1 is 34V, also on R1 .. the voltage on U1, 6pin is 11.2V and it doesn't change if i move P1 .. voltage on U3 is always 34V it doesn't change ... but if i move P1 the voltage on R9 changes from 0.5V to .. 11.11 If you need any more measurmeants u ask ;) PS: and of course ... sorry for my bad english
  15. Hi! ... i'm new on this forum so i have some maybe allreday answered questions... sorry ;) i'm wondering if someone has made a 5Amp modification and use the LM338 insted of LM317? is there a new PCB for that or something? Tell me what u changed... I'm also thinking to do a dual power supply. that's two adjustable power sources. Can I build two PCB's and then use transformer whit "double secondary connectors".. i hope u know what I mean... and use it like that whit no further modification... Thank you!
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