Working more and more with semiconductors, the crude power supply with analog meters didn't satisfied my need anymore. I wanted more precision and above all more solution. From the replacement
circuit for a 7805, I stated developing my power supply.
The power supply has a LM358 as regulator for each channel, a BD243 as driver and two heatsinked
2N3773 as power stage. The LM358 is
powered from a 7824, and the reference, a ICL8069 from a 7805.
The outputs are isolated from earth and from each other. So they can be connected in paralel or series, without problems. Earh terminals are provided for each channel in case that connection is needed. The pots are of course ten turn ones. Like the 7-segment display, they have been bought on Aliexpress, the are so much cheaper there. The 10k version costs 1.5€, the others a bit more but if time doesn't matter, then you should go for them. The quality is good. The same goes for the display. It has a resolution of 10mA and 100mV. It can be adjusted with some tiny pots one the backside. The outputs are switched by relays and the status is shown by leds. There is also a button, when pressed, a relay shorts the output, so the maximum current ca be adjusted.
I designed nearly everything. I just copied the current regulations from google images. It consists of a potentiometer, a shunt and a transistor.
As usual I link the datasheets from pages found on google, because I don't own them and books with datasheets are rare these days :(.