Hi,
I was going to ask for help here with my TMNT machine having very loud buzzing noise coming from the speakers which increased when I install a Rottendog PSU card to an unbearable level and it was at the noisiest level during the attract demo.
You probably already know this but I was so happy, proud and to surprised to be honest of myself of fixing it, I thought I'd post here of my findings.
During my searching I read that Data East noise is a common problem, a lot of suggestions was to check and replace capacitors on various boards, which is out of my league and they all looked in good condition to my untrained eye. I also read that bad earth to the cards can also cause this, so this was something I was capable of doing and followed the suggestion and I tightened all the screws on my sound board, saw that one was missing but I found the screw was stuck on the magnet of the back of the speaker (lucky find) so I reinstalled that too. I turned on the machine and the noise was still present.
I read on that people had success with unscrewing the sound board and free floating it, so I tried that and it was still the same noise level and reinstalled it to the back board.
I thought I stuck with this noise problem and just as I was closing the back board up I noticed the CPU board also had a screw missing so I looked around and found a screw and whacked it in and checked all the rest of the screws to make sure no more was going to fall out. After a few hours I thought I'd have a quick game so i turned on the old girl and I was amazed that I only had a very very slight buzz synced with the lights flashing. I was amazed that a one mounting screw missing could cause such problem.
Cheers
Andrew.
