Recently I have designed a variable 30 vdc output power supply When I tried it on the breadboard it worked fine and gave me a maximum voltage around 29.8 vdc When I tried to design the PCB ( its my first PCB ever ) And it has a lot of mistakes I know But I don't know why but the maximum output voltage is just 20 vdc And when I increase the potentiometer above that voltage The multimeter reads nothing (open loop I guess) So what could be the problem ? Is it one of the capacitor ? Is it damaged because of the heat applied by the soldering iron ? Can I fix it ? enter image description here enter image description here enter image description here

  • \$\begingroup\$ Please use standard English grammar and punctuation; your post is very difficult to read. \$\endgroup\$ – uint128_t Jan 31 '16 at 6:59
  • \$\begingroup\$ Your PCB is not horrible, but I would cut the pins flush with the board, and then measure the conductance for each trace with a multimeter to check if it was etched through somewhere. Then check for shorts where the solder joints are close to each other. \$\endgroup\$ – pipe Jan 31 '16 at 10:01

Check C4 is inserted with the correct polarity.

Check voltage on LM317 input is more than 30 volts.

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