Hello all!
Hopefully this tip will help someone in the future.
My friend sent me a Macintosh SE/30 that was previously recapped, but the previous person didn't clean the pads before putting new caps on. Therefore, it had to be recapped again! Their machine was getting the dreaded Simasimac at first. However, after my recapping and repairs... that stopped... and this happened instead!
This drove me mad for a while. Well, recently I was looking at this board again. I re-seated all the chips and replaced some of the Ux8 row of chips... but the issue persisted. Then, just for fun, I swamped the Video ROM from a known-good system... and ta-dah, success!
Now maybe not all Video ROMs fail in this way, but I thought it was interesting to note. Sometimes the patterns changed slightly, but it was usually with several rows of horizontal lines and checkered patterns.
The next step is to find a replacement Video ROM chip that I can program, I have a few suggestions, but if anyone happens to have a part number they've used, feel free to add it.
Hopefully this tip will help someone in the future.
My friend sent me a Macintosh SE/30 that was previously recapped, but the previous person didn't clean the pads before putting new caps on. Therefore, it had to be recapped again! Their machine was getting the dreaded Simasimac at first. However, after my recapping and repairs... that stopped... and this happened instead!
This drove me mad for a while. Well, recently I was looking at this board again. I re-seated all the chips and replaced some of the Ux8 row of chips... but the issue persisted. Then, just for fun, I swamped the Video ROM from a known-good system... and ta-dah, success!
Now maybe not all Video ROMs fail in this way, but I thought it was interesting to note. Sometimes the patterns changed slightly, but it was usually with several rows of horizontal lines and checkered patterns.
The next step is to find a replacement Video ROM chip that I can program, I have a few suggestions, but if anyone happens to have a part number they've used, feel free to add it.