Dec 062015
 

I got this Wardner PCB for a repair from my friend Zoran:

Wardner_PCB

Gameplay was fine except for some minor sprites glitch in form of some sparkling dots:

sprites_issue_

Studying a bit the hardware, I could figure out where the sprites circuitry lied:

sprite_circuitry

The four EPROMs were dumped good, the six 2148 RAM were fine as well.But when I probe the three 74ALS169 with my BK550 logic comparator I got trouble on pin15 of the ones @B21 an C21:

74ASL169@B21_@_faultyC21

74ASL169@B21_@C21_compare

I desoldered them but they tested fine in all my programmer.I replaced them anyway and this cleared the sprites issue.Job done.

 Posted by at 10:56 pm