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  1. M

    iMac G3 green light of death

    I powered my trusty old iMac G3 Rev A after about 2 years. It powered right on, and it stayed there, until the sleep timer kicked in and machine went to sleep. When I wanted it to wake up, it did wakeup, sorta, but the screen was blank with the green light on. When I turned it off via a power on...
  2. M

    Macintosh Classic II blank screen after recap

    Yeah, however I thought that these boards are only 4 layer (bottom, ground, power and top plane)... If it is in a layer that I can't see, is it even possible to repair it somehow? I also reflowed the capacitors on the bottom side, but it also did nothing. Also replaced the memory chips... It...
  3. M

    Macintosh Classic II blank screen after recap

    I finally made some progress. I managed to get the chime and white screen. It looks like there is a broken trace or perhaps a component that likes heat. If I heat the board with the heatgun in the area underneath the Egret chip it will chime sometimes, sometimes it will do a jailbar pattern...
  4. M

    Macintosh Classic II blank screen after recap

    Thanks, The Egret is fine. Well, I would be glad if there was any cap goo, but as I said, this board was very clean. And trust me with that, as I recapped at least 50 old Mac's boards, so when I find a clean one, I know it. I cleaned it with a mixture of degreaser and distilled water about 4...
  5. M

    Macintosh Classic II blank screen after recap

    Ok, I've swapped the Egret from another Classic II (Rev. 1) board, but it didn't help at all. The Egret chip was definitely okay, as it works okay on the other board. Also when I tried the working board with the Egret chip removed, it was completely dead, the exact opposite of what the broken...
  6. M

    Macintosh Classic II blank screen after recap

    I am returning to this board after 2 months, the situation is the same. I've pulled all the small chips, U1,U2,U3,U4,U5,U6,U7,U10,U11,U12,U15, but it will only display checkerboard wihtout U10 present (Egret). Others don't make any difference in operation. I also did the RC1, RC2, RC3 - no...
  7. M

    Macintosh Classic II blank screen after recap

    I removed the U1, U2 and U4. Also removed the U14 RAM chip. There is no cap goo damage. See the attached pic how clean the traces are Still the reset line gets stuck on and I get blank screen. I believe that something connected to the U10 Egret chip must be shorted as without the Egret chip it...
  8. M

    Macintosh Classic II blank screen after recap

    Thanks. I'll do that. ASC chip is which one? Hmm, would the bad ram cause blank screen error? To clear what I've written before: the EGRET chip is not the culprit, as when I swapped it with the one from LCIII, it didn't help at all (I got blank screen). However without the EGRET, I get...
  9. M

    Macintosh Classic II blank screen after recap

    I swapped the EGRET with the one from the LC III, but I have the same error. The reset line gets pulled low and nothing happens. So perhaps is also this EGRET chip dead, but I suspect a problem somewhere else.
  10. M

    Macintosh Classic II blank screen after recap

    I have a dead LC III logic board with major battery leakage. I'll swap the EGRET. What this EGRET even does? ADB and stuff? Should the board boot to the insert disk icon without this chip? I tested the board with the case removed. Sometimes I tested it without even the board in the computer...
  11. M

    Macintosh Classic II blank screen after recap

    I was looking at the hot air gun on my desk for some time now. And I figured, prehaps is the sound IC dead, as I soldered the wrong capacitor. So I took it off. The problem however, presisted. Then I pulled the U10 (EGRET, 341S0851) and now the reset line isn't stuck anymore. Finally some...
  12. M

    Macintosh Classic II blank screen after recap

    Roms are in correct places... I've pulled them a few times and the pins are like brand new. Also found out if I leave the board long enought powered off, when turned on, the reset line will jump to a 3.2V for a second and then drop to 0.2V..
  13. M

    Macintosh Classic II blank screen after recap

    Thanks. The board was super clean to begin with no visible goo damage. There was very slight leakage under some of the caps when lifted, but no corrosion. I cleaned now the board about 3 times, the last time I left it in isopropyl alcohol overnight and then dried it. None of the pads are lifted...
  14. M

    Macintosh Classic II blank screen after recap

    Ok, I got the 68030 pinout and traced the reset line. It is being pulled low.
  15. M

    Macintosh Classic II blank screen after recap

    I figured that. SE/30 has manual brightness adjustment. I borrowed another Classic II from a friend and swapped logic boards. My analog board is fine, as I booted it up with friend's logic board. So my logic board is clearly completely dead, as it also won't start in his Classic II. It also...
  16. M

    Macintosh Classic II blank screen after recap

    I've soldered the new caps, but it is still dead as a dodo. I probed a using an oscilloscope around the board, but found no activity, just voltages sitting there. Only the oscillators seem to be running... After about 15 minutes, only the CPU and the VLSI chip got a bit warm, other chips were...
  17. M

    Macintosh Classic II blank screen after recap

    I've removed all the "new" caps to inspect the traces under a magnifying glass. I checked almost all of them for continuity and found no broken traces. I was a bit sloppy when removing old caps, so I scratched the board one or two times near the caps, but even these nearby traces are intact. I...
  18. M

    Macintosh Classic II blank screen after recap

    It is an Enhanced Audio revision Logic board. I checked the traces around the caps and found no breaks. I also ran a diode meter through the ceramic caps at the bottom, and found two that are shorted to ground. These are C18 and C40. They are both connected to the ground plane at the one side. I...
  19. M

    Macintosh Classic II blank screen after recap

    I just acquired a mint condition Classic II. It was described that it shows only checkerboard pattern. When I got it, it powered on and it showed checkerboard without chime. The HD also starts. Then I recapped it, but now the screen remains blank, also without chime. The logic board was in...
  20. M

    512k repair

    Ok, I replaced the capacitors (100uF 250V) and diodes (used the 1N4007s).I used the brake fluid on the case and the old paint is starting to peel off easily :) After that, I tested it. It chimed, but the screen remained dark. Also the cathode heater in the CRT was glowing quite strong. Next...
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