A3000 sync/video issue

[jammarob]

I know, another "A3000 with leaking battery" thread.

Fortunately, the leaking battery was removed years ago, however, the previous owner did NOT clean up the acid.

It has started to develop multiple video issues. First, the 31KHz video output stopped working. 15KHz RGB is fine.


Here is a photo of some of the corrosion:


Do you guys have any ideas of possible specific chips or parts to check? This thing was working beautifully a year ago, but it seems like it is slowly bleeding to death .

[jammarob]

Thanks guys! Will the Endivision ECS allow me to continue using 15KHz video? I do like having this connected to the PVM.

I have pulled the Denise chip and it is clean as a bell, however, the socket looks like someone's science experiment. I think I will need to pull the socket with green pins and replace, for starters...

[jammarob]

The Denise socket is definitely corroded. All of the pins are very green.

I can pull it myself, but I will have to borrow a friends Hakko desoldering station.

[jammarob]

So a quick update:

This weekend I pulled all of the socketed chips in the video section and inspected the chips and the sockets.

I replaced the 48-pin DIP sockets for Paula and Denise, as they were both corroded. The PLCC socket for Fat Agnus was also replaced as a precaution.

I am still seeing some weird sync issues. Does anyone know what this part is:



It looks like a potentiometer of some kind, and it is heavily corroded on my board. The sync jumps around if I try to adjust it.

Vsync is 60Hz as it should be, but Hsync in 31KHz mode is measuring at 48KHz!

15 KHz is now working fine though!

[jammarob]

So after some thought, I think I am just going to get an Indivision adapter. I hate that the onboard video is not working 100%, but this will certainly resolve the issue.

At least all of the sockets for the video ICs (except for Amber) are new and no longer green with corrosion.

[jammarob]

Send it to Anthony.
http://amiga.serveftp.net/

I appreciate the suggestion, but shipping + the cost of the repair would well exceed the price of the Indivision.