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  1. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    I mean normal as in the wrong voltage we've been seeing previously
  2. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    If Q3 is not the guilty party all that's left is incoming power: D13: 41.6/31.6V R19: 31.6/30.8V R20: 30.8/ 1.7V C8: 1.7/0.8V(normally 0.9V) Who's on the firing line?
  3. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Am I reading your Rev 6 schematic correctly? On the BC547: Base is connected to R19, R20 Emitter to D13 Collector to R22
  4. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Audioguru, thanks for taking the time to look it up. Now the question posed in post #182 appears again
  5. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    ESR meter to the rescue: face up 1 2 3 C B E So it is correct turned around if the S9015 image is correct
  6. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    This is the actual product I bought: https://www.mantech.co.za/Datasheets/Products/BC55X-IC-4L.pdf I find it confusing/ambigious
  7. bushtech

    Finding a nano amp transistor for Solar LED Light Marker

    I hope the garden solar path lighters in the UK are better than the rubbish we get here on the tip of Africa
  8. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Aaaargh! Still got it wrong! It's the emitter of BC557 connected to R20
  9. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    But the bigger question is do I have the transistor the wrong way round. Here is the transistor I'm using: BC557 Am I correct in saying this view is with the flat side down ? And here is what I think is a view of a 2SD9015 Now looking at them again, am I right in saying that the transistor...
  10. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Apologies: This is what I should have said: By swinging the Q3 (BC557CG) around I have it's base connected to R20 (30.1 & 1.79V) and then through C8(1.79 & 0.9V)to U2 pin3 at 0.9v So either the drop through one of the components isn't big enough or I am starting off with too high a voltage.
  11. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    By swinging the BD139 around I have it's base connected to R20 (30.1 & 1.79V) and then through C8(1.79 & 0.9V)to U2 pin3 at 0.9v So either the drop through one of the components isn't big enough or I am starting off with too high a voltage
  12. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Audioguru, you are on the money! Looking in the wrong place I was. Which brings up the question: Did I correctly turn the transistor around. Here is the link to the BD 139 I am using. As far as I can see the pins are reversed to the original 2SD9015...
  13. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Thanks Audioguru Working back from Pin2 of U3: Pin 2 = 0.93V to R21 = 0.93/0.002V (still in situ, leg not lifted) Reads 9.95kΩ to Connection point R4 = 0.002V to CP R6 = 0.002V to Pin 4 of U1 = 0V So components behind R21 all at 0.002V. I don't understand how voltage could jump from 0.002 to...
  14. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    So can I reconnect safely?
  15. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Oh, and I still have R12/C6 connected to pin 6
  16. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    This is where it gets a bit weird. I couldn't really understand why it suddenly started working. But then I noticed that I had lifted the one leg of D9 to check it. So I soldered the one leg of D9 back and checked it again and I'm back to about 7V max. So D9 has got something to do with the...
  17. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Not so sure I share your confidence. this psu, think I'll name it Frankenvolt when it's finished, has bitten me you know where, too often :)
  18. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Audioguru, Ok, If U2 's only job is to V from 0 to 30V when P1 is turned then U2 is working fine (acually 34.4V fine) And Pin 3 to 6 ratio is about 2.7x. This is with new U2. Don't know why it's working, as long as it's stable. Now, as soon as I get a gap, I'm digging into the hot U3 Thanks...
  19. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Audioguru, Ok, If U2 's only job is to V from 0 to 30V when P1 is turned then U2 is working fine (acually 34.4V fine) And Pin 3 to 6 ratio is about 2.7x. This is with new U2. Don't know why it's working, as long as it's stable. Now, as soon as I get a gap, I'm digging into the hot U3 Thanks...
  20. bushtech

    Chinese Hiland 0-30V/Audioguru PSU build (down the rabbit hole)

    Got no spare C8's. Looking at replacing all original components supplied by banggood. With R12/C6 connected to pin 6 of U2 where do I measure output voltage? Pin 3 of U2 has got virtually no voltage on it - not stable. Looking at the 0.94V on pin 2 of U3
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