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    0-30V Stabilized Power Supply

    No, this is the most recent parts list / circuit diagram: http://www.electronics-lab.com/forum/index.php?topic=19066.msg1010703#msg1010703 I really think someone should update the frontpage to the most recent version. That way everyone would find the most recent version of the circuit and it...
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    0-30V Stabilized Power Supply

    The latest circuit diagram can be found here: http://www.electronics-lab.com/forum/index.php?topic=19066.msg1002666#msg1002666 According to this application note from Fischer Elekronik (heat sink manufacturerer)...
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    0-30V Stabilized Power Supply

    More pictures. Not quite sure which variant I want to use. 2N3055 on a L-profle mounted on the heat sinks or TIP3055 mounted flat on the heat sinks.
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    0-30V Stabilized Power Supply

    I've got four TIP3055 (TO-218 / SOT 93) here, and two 2N3055 (TO-3). I've decided to use silent CPU coolers. I am uncertain if a single BD139 will be enough to drive four TIP3055s. I am only aiming for 30V / 3A output, so the additional TIP3055s would just be there to compensate for the lower...
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    0-30V Stabilized Power Supply

    Very nice. Is this the latest REV2 version of the PSU or the original version? The shematic seems to be different, and you're only using one output power transistor.
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    0-30V Stabilized Power Supply

    In any case a smaller Kelvin per Watt value is always safer. A heat sink with 5.24 K/W is most likely more expensive than one with 11.9 K/W. Florian
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    0-30V Stabilized Power Supply

    Nothing wrong really. Audioguru either made a small typo and actually wanted to type (130°C - 76.4°C)/4.5W = 11.91K/W or he substracted another 30°C of safety margin from the maximum junction temperature value of 130°C. (130°C - 30°C - 76.4°C)/4.5W = 5.24K/W Florian
  8. L

    0-30V Stabilized Power Supply

    I noticed that only the original Philips datasheet of the BD139 specifies a value for fT = 190 Mhz. So far I haven't found a transistor in the TO-220 package that's that fast.  I think the fastest one I've found so far is the 2SD1762 @90Mhz or so, but the dc current gain doesn't seem to be as...
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    0-30V Stabilized Power Supply

    Ah thanks. I'll have to adjust my calculations then. I've got a 160 VA transformer with 1x 230V primary and 2x 15V (5,33A) secondary windings. Im going to put the secondary windings in series so the resulting RMS voltage should be 30V. My rectifier bridge drops 1.1V for each diode inside of...
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    0-30V Stabilized Power Supply

    Hello once again. I still haven't managed to build this supply even though I designed my own PCB, which probably is still crap. Who cares. The reason I post here today is because I finally want to finish the PSU and I am not sure what type of heat sink I should pick for Q2 (BD139). It only says...
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    My own PSU-PCB (30 VDC / 0.002-3 A PSU REV2) [WIP]

    Thanks for the hint regarding Q3. That sure saved me a lot of trouble. I revised my schematic so that the ref names of the components in the schematic are matching the original schematic. Also it should be a little more easy to read it now as I used bigger font sized in most places. I also...
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    My own PSU-PCB (30 VDC / 0.002-3 A PSU REV2) [WIP]

    Sorry about the popups. I usually use some ad blocking meassures (like Adblock+ or Proxomitron) to get rid of ads. So I didn't even notice the pop up infestation of that page. I will re-upload the files once i get my main PC back to work (currently using my gaming PC). Um ... I recon that not...
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    My own PSU-PCB (30 VDC / 0.002-3 A PSU REV2) [WIP]

    Note to self: Values of RV3 and RV1 are switched in the shematic. RV1 needs to be the 5K poti and RV3 needs to be the 100K poti.
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    0-30V Stabilized Power Supply

    Oh yeah you're right, I actually leared that stuff at technician school, but I am a little rusted. I think there is also a spreadsheat by Fischer Elektronik that explains the process. I'm going to look it up. Found it: >> PDF <<
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    0-30V Stabilized Power Supply

    Hello again, I got a question regarding the heatsink of the BD 139 transistor. I think "a pretty big heatsink" is a bit vague/relative. Could someone translate "pretty big heatsink" into a
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    My own PSU-PCB (30 VDC / 0.002-3 A PSU REV2) [WIP]

    Hi, I am currently in the progress of routing my own PCB for the 30 VDC / 0.002-3 A PSU REV2. I started this topic to share my progress on this project with you. One might ask "Why creating a new PCB Layout? PCBs are already available?". Well to answer this question you got to know that I am...
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    0-30 Vdc Stabilized Power Supply

    Hi audioguru, I didn't even notice that this (*click*) post was from 2007. No wonder the parts list doesn't match! I am having trouble finding the right documents though. Couldn't find the parts list anywhere in the last 12-13 pages. And I think others will have this problem too.You partly...
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    0-30 Vdc Stabilized Power Supply

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