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    0-30 Vdc Stabilized Power Supply

    yea im not sure, im in new zealand, but even things like TL081 which i found in the end. for $1.61NZD. thats less then $1 US and the 2n3055 for $2.20NZD. maybe the OPA445 is just rare and thx. ill try one of the 44V op amps
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    0-30 Vdc Stabilized Power Supply

    Hi, I am using HA17741 op amps which are rated at below the almost 40V supplied to them. for a 36V op amp. tho replacing them for the TL081 wouldn't really fix that would it, they are 36V also?  Which is why they failed. or so i think they did. not sure how to test that. U1 and U3 have...
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    0-30 Vdc Stabilized Power Supply

    Hi, I've just finished making this PSU, and even tho it seems to run ok. a bit hot atm but ill pick up some bigger heatsinks soon enough. I want to learn a bit more about how it works. eg How to work out how much heat things might generate and what heatsink is going to work best D8 is a 5v6...
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    0-30 Vdc Stabilized Power Supply

    Thx for the info audioguru, it seems the PSU works better with the correct value at R7 0.47 and not 47ohm now that i can run it over 50mA, looks like i will have to find some better cooling for this power transistor :p 15V at 2A for a few mins and the whole heatsink is pritty hot. small...
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    0-30 Vdc Stabilized Power Supply

    Hi, I have made the standard PSU from the projects page, and am after some help with troubleshooting. the few changes in parts -TL081 for HA17741, which seem similar. -C1 is a 4700uF / 63V -C4 i used two 53nF -Q2 is a TIP31C, with bent legs to fit the original PCB design -Resistors are half...
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