Donkey Kong PCB cap kit? (audio hum and siren noise)

[VWbus]

Is there one PCB or two PCBs in the supply? I vaguely remember there being 2 PCBs. Check the other one.

I actually found  my copy of the manual and it has a cap map in it. I have never seen this published online so I will be scanning it in this week and fixing the instructions for that kit.

Yes, there are 2 PCBs when you open the power supply. I checked both PCBs last night looking for C2 and that is only one I could find. All the other caps I could find except that one. I'll give it another look when I am home tonight. The boards are filthy. I really want to wash them with some simple green and water but I have a sneaky suspicion that would be a bad idea. Even if I let them dry for a few days.

[iankellogg]

you could wash it with water. I use the dish washer all the time. It does leave a slight residue behind but its easy to clean that up.

no soap, no added heat, no heat dry cycle on the dishwasher.

You can dry the PCB in the oven at 150F for 30 minutes to an hour.

[VWbus]

you could wash it with water. I use the dish washer all the time. It does leave a slight residue behind but its easy to clean that up.

no soap, no added heat, no heat dry cycle on the dishwasher.

You can dry the PCB in the oven at 150F for 30 minutes to an hour.

Awesome tip. Thank you!

I'll report back on the C2 search. Thanks again Ian, you're the best!

[VWbus]

Ian,

I did find the C2 cap last night. It was located on the other PCB:



I couldn't see it until I cleaned the filth off the board!

I should have this whole power supply capped by the end of the week. Crossing my fingers this solves (or at least helps) my audio hum and siren noise.

[johnrt]

Hi there! Did you ever fix this issue? I have a faint background "siren" noise on my boards as well. I've read a lot about and it just seems to be some kind of "weakness" on the boards, and that you will have to live with it. But if someone find a solution it would be great.

[P-feif]

Hi there! Did you ever fix this issue? I have a faint background "siren" noise on my boards as well. I've read a lot about and it just seems to be some kind of "weakness" on the boards, and that you will have to live with it. But if someone find a solution it would be great.

Start watching at 21:15.

https://www.youtube.com/watch?v=k6mdj0dLjss