Hi everybody. I'm a newbie. I've spent some time reading this topic, and for me was very helpful to understand the functioning of this power supply. It’s true that I didn't finished yet the entire topic, but I will do this in the next period. With your permission I will ask you a few questions about this project.
First of all, obvious I have started this project from the original faulty diagram, buying a kit of this PS, but without transformer. Now, I'm trying to finalize a good upgraded diagram for the 3A version. The questions are:
1. What do you think about using a MJE3055 instead of 2N3055. I intend to use two of them mounted on a PC processor heatsink with fan?
2. I know that in the latest version of this PS, U3 is powered through a 10V zener. Why we don't use the same method for powering the U2? Assuming a 30V transformer @ no load, we will have around 41V between pin 4 and 7, that is close to the 44V limit of opamp.
3. It is correct if I calculate the voltage drop, from transformer to the output, like this: 2V on the transformer, 2V on the rectifier bridge, 1.4V on R7, 2V on Q4/Q5 transistors? All losses are assumed for a 3A load.
4. Do you think it is possible to have a voltage ripple below 10mV using a 10000microF and a 28V @ 5,35A transformer.