Recent content by Smitjuh

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    0-30 Vdc Stabilized Power Supply

    Ha thats my thought... I already did a few tests with a meter acros R7 and it works wel, it needs some math to get it right but I will make it work!
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    0-30 Vdc Stabilized Power Supply

    YES!!!!  ;D ;D ;D ;D ;D ;D ;D The thing works perfectly by now!!! It indeed was a short betwwen pin 6 and 7 a nasty one, but all short are nasty one's!  ;D ;D I can't thank you enough audioguru!! I will place pictures when it is in it's housing! one thing... what is the best place to add my...
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    0-30 Vdc Stabilized Power Supply

    :( I already tried the swapping option.... The op-amp isn't the problem. Can't there be a problem with one of the transistors? I will check them for bad working of wrong placement later this day.
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    0-30 Vdc Stabilized Power Supply

    Output of U3 is 33,5 V. Values of R20 and R19 are like described in the project, 10k and 2,2k. So not wrongly painted, or got a alightly different color due to heat or something. I checked the PCB several times on shorts, but I can't find any. The 24V can be al bit more, I read it quickly on a...
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    0-30 Vdc Stabilized Power Supply

    Audioguru, I changed the op-amps to TLE2141CP one's. The supply regulates ok. At a full load, it won't exeed 24V. But with all the losts in the supply this seems ok. But my LED still won't light... U3 get's realy hot... maybe that rings a bell? Greetz
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    0-30 Vdc Stabilized Power Supply

    NO it isn't. Like audioguru mentioned in one of it's earlier posts, you can change R7 to other value's. If you give it a higher value, the max. current will drop.  ;)
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    0-30 Vdc Stabilized Power Supply

    Shooter, You can use 2x 0.22 Ohm 5W resistors in serie! Then you got a 0.44 ohm 10W resistor... It's just a thought...
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    0-30 Vdc Stabilized Power Supply

    Hi audioguru, Here I am again  ;) I changed my op-amps to 44V rated ones (op37 from Analog) But With the last op-amps I could regulate from 0-32V, but now It is only possible to about 24V. And when the supply is powered for some time, the voltage decreases slowly. down to 22V.. When currents...
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    0-30 Vdc Stabilized Power Supply

    Hello! Audioguru! In your last post to me, Changing U2 and U3 was a option.. well, option it was nescesarry because they where working outside their workingvoltage. Well I changed them with LM741's. But there is no difference in the working of my powersupply. If I turn my Potentiometer P2...
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    0-30 Vdc Stabilized Power Supply

    Positive supply: 34.4V Negative supply: -5.65V Drop at 3A: about 1V (34.4 to 33.5) Voltage on the outputconnectors also drops a little when turning P2 down. So I can control the current, but only for a very small part....
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    0-30 Vdc Stabilized Power Supply

    with a 10k resistor on the base of Q3 the LED lights! I've tested my opamp (U3) little comparator test, and this one still works. (AD711 Analog Devices) But my Supply voltage goes down... the voltage connected to the collector of the 2N3055...
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    0-30 Vdc Stabilized Power Supply

    Hi!! I replaced some components with the better components mentioned by audioguru. The BZX zener and the both TIP31A's also some resistors. But my LED won't light!! The output from U3 (pin6) is 34V when pin2 is in voltage value above pin3 Pin6 remains 34V. but when I turn back P2, pin2 of U3...
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    0-30 Vdc Stabilized Power Supply

    Hi audioguru, I changed R4 to a 1K value, and my Voltage value has climed from 10.7 tp 11.2V!! I did not used the BZX zener, but this one will be delivered soon I hope. I looked at you're schmatic and see that the voltage acros R7 becomes 1,4V when there is a current flow of 3A. I tried it...
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    0-30 Vdc Stabilized Power Supply

    Hi audioguru, reading this forum, you're the man for all my questions ... I think  ;) As entioned before in this topic, my current control circuit won't work properly. I will give some measurement results. On Pin 3 I can control the voltage from 0 to 1,7V (no load) witch is correct, because...
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    0-30 Vdc Stabilized Power Supply

    Pin 2 of U3 becoms more negative when I turn up the output voltage... I can't realy find why..
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