Tetris repair

[Martinmurphy30]

Hi folks, first repair log here. Offered to look at a couple of PCBs for a member here so first up was Tetris, original Atari board completely dead. Did a visual inspection and it was completely original, pulled all socketed chips and cleaned all legs and sockets, verified ROMs...all ok. Put it back together and fired it up, no video, logic probe on the CPU showed it was running, measured the sync..fine, measured r,g,b totally dead. Had a look at the schematics and went to the 6116 video ram, logic probe showed activity on all address lines but data bus was stuck

piggybacking the ram and probing the data bus got me..

. Good so faulty ram it is then, cut that ram out and cleared all the holes with no dramas, fitted a new socket and nos 6116 ram equivalent, fired it up and...

So now it's working I changed all the nasty electrolytic caps out for new fresh ones....repair complete.

Martinmurphy302021-04-30 22:49:09

 

[TheDaddy]

Hey ! Tetris are my thing !! Lol

Nice repair mate , these are great to work on. Your lucky its just ram , i am never that lucky

Dave.

 

[Martinmurphy30]

Thanks Dave! Yeah I have no luck normally with these things! Thankfully both pokeys and the eerom seemed to be ok, so was a nice straight forward repair.

 

[RonocTheBrave]

Martin thank you so much for the repair, so glad its working. Its my first working pcb in my collection

 

[Martinmurphy30]

Your very welcome! Hopefully keeps going for another 30+ years!??