| Electronics > Projects, Designs, and Technical Stuff |
| Chinese 0-30v 3a psu issues |
| << < (3/6) > >> |
| m3vuv:
well i changed q4 for a 3055,still no voltage spikes but only just over 9 volts out into a 21 watt bulb,any ideas? |
| wraper:
BD139 has different pinout. So most likely that's the reason of 'fix' and becoming broken. You just assembled it incorrectly. Also BD139 is not a right part to go there. |
| xavier60:
Measuring the voltage drop across R15 will indicate how much current U2 is supplying to drive the output stage and how much current gain there is. |
| m3vuv:
its not the wrong pinout!! |
| m3vuv:
For what its worth if i lift one leg of R11 and one leg of C9,it still behaves the same,voltage adjusts to a max of about 9v and the current limit still works. |
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