neonmegadrive
Student
Hey guys,
So, I've purchased many different working M72 boards at a great price recently. While they work they also show heavy signs of age. Normally, my process when cleaning these boards is, teardown, clean, recap and rebuild with a Semload case. However, This time around my Image Fight, after rebuilding, booted with only SOME sounds playing. Specifically those sounds would be just the blasters, ship boosting and a few other enemy sounds. No music at all and many other sound effects missing.
I tried reseating everything, checking for physical shorts (stray debris) and even tried another known working set of Image Fight IC's. Still same result. I then tried the middle board (M72-A-C/D) from my X-multiply in place of the Image Fight board and everything started working / sounding fine. So that narrows down the issue a bit to the middle board. I do recall having a bit of trouble when removing a cap underneath the heatsink. So thinking I may have pulled a trace there. I've redone all the caps very carefully and inspected all the traces in that area. Now there is NO sound at all.
I've scoured the web and found a few folks with similar problems but I'm still having a bit of trouble. I do not have a logic probe yet and have limited knowledge with that tool. Any help would certainly be appreciated.
I know @caius is an M72 expert, if you have some time to spare, I will be so grateful. Thanks in advance!
So, I've purchased many different working M72 boards at a great price recently. While they work they also show heavy signs of age. Normally, my process when cleaning these boards is, teardown, clean, recap and rebuild with a Semload case. However, This time around my Image Fight, after rebuilding, booted with only SOME sounds playing. Specifically those sounds would be just the blasters, ship boosting and a few other enemy sounds. No music at all and many other sound effects missing.
I tried reseating everything, checking for physical shorts (stray debris) and even tried another known working set of Image Fight IC's. Still same result. I then tried the middle board (M72-A-C/D) from my X-multiply in place of the Image Fight board and everything started working / sounding fine. So that narrows down the issue a bit to the middle board. I do recall having a bit of trouble when removing a cap underneath the heatsink. So thinking I may have pulled a trace there. I've redone all the caps very carefully and inspected all the traces in that area. Now there is NO sound at all.
I've scoured the web and found a few folks with similar problems but I'm still having a bit of trouble. I do not have a logic probe yet and have limited knowledge with that tool. Any help would certainly be appreciated.
I know @caius is an M72 expert, if you have some time to spare, I will be so grateful. Thanks in advance!
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