I have this old homemade digital clock which i'm trying to revive. It has sentimental value as it was built by my dad in his youth.
The problem is 2 of the segments only sometimes light up on the third module. There is no part number visible.
It doesn't look like it's a bad connection, i've resoldered most the wires that go to that module and as i've said, it occasionally works out of the blue..
I'm not sure where to begin investigating. I understand what most components do, but i'm a newby in electrical engineering. Any help appreciated.
My next idea is to start replacing components.. but i'm not sure how to check for bad components on the board.
I added the boost module in order to power it from 5v instead of 220v mains. The output is set to 15v as that was the value written on the board.