I am new to electronic circuits.
I built a basic led circuit on a breadboard to test everything out.It worked as in pictures,but the connections were not stable because the holes were very large.I started soldering some connectors for easily using the supply (it was the first time soldering something). After that it didn't work anymore...I believe maybe I melted the T05 part of the supply(it's close to the positive hole).
1.Why did it stopped working?I tried remove the connections(but I don't have anything to drain the metal).
2.Can I repair it or is it dead?The little led on the battery block is still working.
3.Why can't I use only a basic battery and place some connectors at the end?
4.Why does this power supply has 3 negative terminals and only one positive?
Thank you in advance!