Recent content by noworries2004

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    0-30V Stabilized Power Supply

    Fantastic news got newmc34071 yesterday and the circuit works perfectly, Found problem in other circuit, pin 4 of U3 was 20V, 187ohms between pin 7 and 4 so chip blown, Working perfectly now, Thanks a million for your help everyone especially Audioguru and Redwire.
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    0-30V Stabilized Power Supply

    Just found the main problem i think, 0.33 ohm resistor were connected to the base, So therefore that would explain the high output all over the circuit.
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    0-30V Stabilized Power Supply

    Ok thanks audioguru for your help yet again, I will try and get the mc34071 opamps, and i will get the r7 resistor will let ye know how i get on
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    0-30V Stabilized Power Supply

    Ok starting again with a fresh PCB. All components have correct value double checked all resistors with ohm meter. How ever i am missing 34071 Opamps. The only available opamps are 741 opamps. Is it ok to use these instead? Also i dont have .47ohm (R7) resistos. Will it be ok to leave this...
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    0-30V Stabilized Power Supply

    This is my power supply connected to the bridge rectifier D4 is connected to the pin opposite the rest which connects to r1 and c1, R1 is correct 2.2K, the rest of the parts im possitive are correct,
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    0-30V Stabilized Power Supply

    Just changed the wiper on the 2 pots, prob still there but U2 not heating up as fast Quick question, Think R7 (0.47ohm ) is blown, disconnected it from the circuit and it is measuring 26Kohms, dont have a replacement, is there any other resistor that i could put in. I am measuring all my...
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    0-30V Stabilized Power Supply

    \Audioguru following reststances were taken between collector, base emmitter collector - base  0L Base - emmitter  0L Collector - emitter 2.341 M Ohms
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    0-30V Stabilized Power Supply

    some more pics
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    0-30V Stabilized Power Supply

    Please find the enclosed pics of my project, problem still exists
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    0-30V Stabilized Power Supply

    I have checked the power transistors but i am still getting 41v at the output, I used a single power transistor but still no joy, How can i check if the power transistors are blown?
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    0-30V Stabilized Power Supply

    Thanks audio guru i will recheck the pins of the output transistors, and ill let you know how i got on, yes it is the latest parts list + Schematic Cheers
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    0-30V Stabilized Power Supply

    Current limiting LED is always on, U2 heats up as well ,
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    0-30V Stabilized Power Supply

    Finally connected up m ypower supply unfortunately it is not working, Measuring from Ground, using a 29.4 volt transformer 4 A. I am getting an input to R1 of 41V, how ever i am also getting this 41V at the output, Measuring voltage pot, i am getting  a range from 1.1V up to 10.86V. I am...
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    0-30V Stabilized Power Supply

    Thanks Audio guru, With regards Q1 from last comment would this graph be a fair reflection of what happens when current regulation kicks in?
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    0-30V Stabilized Power Supply

    HI I am currently constructing the updated version of this power supply, I have a fwe questions about this power supply. Q1 ; What happens when current limiting kicks in, does the output voltage drop or does it stay steady. If current limiting is then does this mean that the power supply is a...
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