Howdy everyone,
I'm hoping some of the more experienced SE/30 restorers here can help me track down an issue following a logic board recap.
I recently recapped the Sony PSU and analog board in my SE/30, both successfully. After reinstalling everything, the machine booted to the desktop with a nice, bright, full-screen picture. Everything appeared to be working except for the startup chime, which was already missing before the recap.
Next, I removed the logic board and replaced its electrolytic capacitors. Unfortunately, after reinstalling the board, I was greeted with the familiar SimasiMac horizontal stripes, similar to those described on page 5 of the Mac SE/30 Repair Guide.
I tried reseating the RAM and ROM SIMM, but the stripes remained.
I removed the logic board again and inspected my soldering, particularly around C6 and C7. Since C6 is such a small capacitor, I suspected I might not have gotten a good connection. I removed it, cleaned the pads, and resoldered it.
After reinstalling the board, the display changed from multiple horizontal stripes to a single, extremely bright horizontal line across the center of the CRT. I immediately powered it down to avoid damaging the screen.
This morning, I performed a motherboard swap to help isolate the problem:
I've cleaned the logic board several times with 99% isopropyl alcohol and cotton swabs and inspected the capacitor connections. The solder joints look reasonably good to me, although I'll be the first to admit I'm still improving my SMD soldering skills!
I've also done some basic continuity testing around C7 and the TWOLINE signal between UG7 and UF8. So far, I haven't found an obvious short or open connection.
My question: Given that the board worked before the recap, what would you recommend checking next? Are there particular capacitors, traces, vias, or video timing circuits that are especially vulnerable during an SE/30 recap?
I have a multimeter available, but unfortunately no oscilloscope.
Any suggestions would be greatly appreciated. I'd love to get this old Mac back to its former glory!
Thanks in advance,
Brian @ Arrowhead Garage
I'm hoping some of the more experienced SE/30 restorers here can help me track down an issue following a logic board recap.
I recently recapped the Sony PSU and analog board in my SE/30, both successfully. After reinstalling everything, the machine booted to the desktop with a nice, bright, full-screen picture. Everything appeared to be working except for the startup chime, which was already missing before the recap.
Next, I removed the logic board and replaced its electrolytic capacitors. Unfortunately, after reinstalling the board, I was greeted with the familiar SimasiMac horizontal stripes, similar to those described on page 5 of the Mac SE/30 Repair Guide.
I tried reseating the RAM and ROM SIMM, but the stripes remained.
I removed the logic board again and inspected my soldering, particularly around C6 and C7. Since C6 is such a small capacitor, I suspected I might not have gotten a good connection. I removed it, cleaned the pads, and resoldered it.
After reinstalling the board, the display changed from multiple horizontal stripes to a single, extremely bright horizontal line across the center of the CRT. I immediately powered it down to avoid damaging the screen.
This morning, I performed a motherboard swap to help isolate the problem:
- SE/30 logic board in a known-working Macintosh SE: Same bright horizontal line.
- Known-working SE logic board in the SE/30 chassis: Beautiful, full-screen desktop.
I've cleaned the logic board several times with 99% isopropyl alcohol and cotton swabs and inspected the capacitor connections. The solder joints look reasonably good to me, although I'll be the first to admit I'm still improving my SMD soldering skills!
I've also done some basic continuity testing around C7 and the TWOLINE signal between UG7 and UF8. So far, I haven't found an obvious short or open connection.
My question: Given that the board worked before the recap, what would you recommend checking next? Are there particular capacitors, traces, vias, or video timing circuits that are especially vulnerable during an SE/30 recap?
I have a multimeter available, but unfortunately no oscilloscope.
Any suggestions would be greatly appreciated. I'd love to get this old Mac back to its former glory!
Thanks in advance,
Brian @ Arrowhead Garage
