kankundachi

Hi omer_faruk : As far as you said this problem,it is probability the noise to cause.Especially power circuit is clean output!? If it has 50~60Hz frequency,then it will cause this problem.You can check this point first. :) Best Regards, Stanley

Hi HelderS : About your opinion,I can realize your feeling.But I think everyone to bring up his experience in this project is very good.Because it will be make this project to tend to perfect.Besides we can study this project by everyone experience.Isn't it? :) Best Regards, Stanley

Hi audioguru : I have fixed my 0-30 Vdc Stabilized Power Supply. It works very nice. Thank you for your kindly support at this period. Besides I have changed the R18 & R11 to VR100K & VR50K. Because the VR100K can be fine tune the current to 3A , VR50K can be fine tune the voltage to 30V. And I have modified my schematic is as below attached file. Thank you again. ;D Best Regards, Stanley Power_supply.pdf

Hi audioguru : Thank you for your kindly reply. I will follow your opinion and try it. ;D Best Regards, Stanley

Hi audioguru : I have found the reason of the minimize current is 670mA. Because R20 original value is 10K,but my circuit is 2.2K. :P After change the R20,the minimize current is 9.1mA,but maximum current is 4.0A. ??? How about your opinion? And,I will upload my schematic,as below attached file. Please you double check my schematic. Thank you very much. :) Best Regards, Stanley Power_supply.pdf

Dear audioguru : If D7 isn't working,the vary with voltage (0~30V) will be exceptional. Isn't it? But I still follow your suggesion to check D7 voltage on my board. The result is -5.50V. Besides I found Q2 bias-emitter voltage is 0.61V,Q4 bias-emitter voltage is 0.63V,R15 voltage is 0.06V(exceptional voltage) when output short. How about your opinion? Best Regards, Stanley

Sorry ! I forgot to say my circuit adjust voltage is no problem. Only adjust current has problem. Thanks.

Hello dear all: Today I have finished the power supply circuit. But now I have a problem that's when the circuit is power on and adjust limit current. The limit current adjust range only 670mA ~ 3.92A. The limit current should be 2mA ~ 3A but my circuit is not. When I found the current range is 670mA ~ 3.92A,U2 output (pin 6) voltage range is about 1.5V ~ 4.*V. Is the voltage range correct? If anyone ever has this problem,please tell me that's why. Or you have any suggesion tell me please,too. Thank you very very much. Best Regards, Stanley