So I just brought a cheap bench power supply from a local market, it was dirt cheap picked one up for Rs 800 or 13$. I wasn’t hoping for anything good in it. I was so curious about what one can pack inside a 13$ power supply that I took it apart before powering this up. As you can (barely) see there are two seven-segment displays one for current and another for current, well that’s a good start then, there was each coarse and fine adjustment which no one likes, with are more problematic in this power supply. We can see a positive and negative terminal and also a mains earth terminal separately which normally indicates isolated power supply, but yeah it’s fake. The wire coming from main has just a two-pin connector and surly enough that there is nothing connected to that terminal its just to fool people.
Here is the back of the LED the main PCB, PCB is a well designed one but the connection to potentiometers are bad.
This is the primary switching transistor directly mounted to the back of the case with a very thin insulating layer of plastic. With poor wire connection to the transistor, well all of the wirings are crappy. The best example for that is that the wires used for connecting the transistor are actually thicker than the mains wiring.
At this price, you anyway cannot expect anything more than this, but according to me, you could make a better product than this at the same price by using SMD components and standardized SMPS IC’s which actually are available. It’s not worth even 13$, it’s basically just paying for the case.
Well now I will be using this power supply case for making a better one, its always awesome to make your own anyway.
