regulated power supply

Thread Starter


Joined Aug 23, 2013
> my name is jaco. i have a project i am to build. unfortuntly the project i
> am
> to build is a regulated power supply.
> the components to be used are:
> diode bridge
> 2000uF 25V
> 200R
> 1N579 Zener - 12V
> 2N3053 or equivalent
> 10 K 1/4 W 5%
> 100 ohm 1/4 W 5%
> 240-20V or nearest value 100VA
> im not entirely sure as to how the circuit works. i have tried using the
> internet but its been unhelpfull. could you please give me a explaination
> please.
> thanks


Joined Oct 2, 2009
We cannot help you without a circuit diagram.
Post a diagram and we can go from there,


Joined Sep 7, 2009
With those components it is impossible to build a regulated power supply. All you can build is a DC source with a zener diode connected to the base of an NPN power transistor. It will have neither voltage or current regulation, but it will put out a semi fixed voltage.
Additional to the posts above, 20V into a bridge rectifier off load will exceed the voltage rating of the 2000uF 25V capacitor. Also why a 100VA transformer with only a 2000uF reservoir capacitor and a small 2N3053 series pass transistor, presuming that's what it was intended for? It may be best to state the requirements of the PSU you want to build, voltage, max current and if you require current limiting and overvoltage protection.

Osama ali

Joined Oct 5, 2013
I am looking for the same project , 0-32v DC and 1A current .. though i donot have schematic diagram , but i know zener diode wont work here , bridge rectifier and capacitor will be used accordingly ....