Well, I will try to find some time and go through all my solder joints again. Now I have some tube radios to repair/recap . But I believe that the board is toast, since I remember powering it on when it wasn't recapped, and it also didn't chime, it just made a very quiet chirping sound.

@trag: Yes I have cleaned the board, probably more than three times. I use mild degreaser/soap detergent when cleaning, usually after recapping, but in this case I cleaned it also before recapping.