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Pawel_K's Achievements


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  1. I can't buy this opamps in my area :-[ Something more popular ??
  2. Which opamps should I buy ?? MC34071AP ?? TLE2141CP ??
  3. Hi Omni I checked R7 and its R47 = 0,47 Ohm R1 resistor is 1W. I used in my project the trafo 25,6V. Audioguru Can you help me ??
  4. I checked voltages with U1,U2,U3 removed. Pin7 of all opamps is 34,4V Pin4 of U2 and U3 is -7,2V Pin6 of U1 is 0V Pin6 of U3 is 35,5V Now D10 diode is not hot. Resistor R1 is hot. I changed in my project: C1 capacitor with 4700uF/50V D11 with 1N4007 Q1 with BC547 Q2 wth BD139-16 TL081 with OP07 There are photos of my PCB: [img width=680 height=511]http://free.of.pl/p/pawel-kolodziej/2.JPG Please help me. ???
  5. I checked PCB and it looks ok. Diode D10 is very hot. I checked also rest of elements and they are ok.
  6. Voltages with removed U3: between 3pin and GND minus 29V between 3pin and + also minus 29V between 2pin and + 0V between 2pin and - 0V Here is the opamp tester. When I put U3 into the tester the diode flash.
  7. GND-PIN2 0V GND-PIN3 2,5V GND is "-" on the PCB ??
  8. I checked voltages. Pin 7 of all the opamps is +32,2V Pin 4 of U2 and U3 is -7,1V Pin 6 of U1 is +10,5VDC Pin 6 of U3 is -4,7V current limit diode is lighting all the time. When the 2N3055 wasn't solder I could regulate output voltage from 0,1V to 1V. Now after solder 2N3055 I can't regulate output voltage. It's -0,6V. :-\
  9. Hi It's my first post on this forum. I built this power supply, but it doesn't ot work. I changed TL081 with uA741. I also changed 2N2219 with BD139-16. I can regulate voltage from 0,1 to 1V. :-[ Sorry for my english.
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