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  1. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    Hoping the CPU is what's bad. The UE10 DSC was really bad on this SE/30, the voltage line broke and probably four other lines were severed as well. Not sure if that could kill a CPU, but anything is possible. I watch the CayMac repair videos and he happened upon a bad SE/30 CPU a few months ago...
  2. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    I used the DMM to look at the ROM slot pins, they are all over the place in voltage, very few are always stuck at +5.05V, but nearly all of them respond to the S1 Reset button being pressed.
  3. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    The Reset pin F12 on the CPU is functional, it goes from +5.05V to 0 - 0.80Mv when S1 is pressed. The only Reset pins that were questionable from the Simasima Repair Guide, were the UB10 and 11 Sony Sound chip pin6's, pin5's can Reset +5.05V to 0 - 0.80 Mv. I can't see the Reset being an issue...
  4. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    I have two different 4Mb sets of RAM that came with this SE/30. I was using the Ti set in the previous pictures. I also have two working SE's here that I tested the RAM in, I put the set on the right in just now and ran the scope. It's the same with or without a CPU in this board, no clean...
  5. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    Looking for some advice on where to go next with this. The problem I'm having is that the CPU will not walk the bus. No matter what pin I'm measuring in the ROM slot, there is no clean square wave. With or without the CPU inserted, I get the same result, no square wave. The Simasima...
  6. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    Tried the ROM/CPU walk the bus test and I don't get a solid square wave from any of the pins, the wave form is a mess. Suspecting a bad CPU. Is there any way to tell a CPU is bad without another to test with?
  7. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    Was measuring RP7 pin7, not pin2, RP7 pin2 does go to 0V with Reset. RP7 is good, my mistake. Added sockets for UB10 and 11, the Sony Sound chips. According to the schematic: Pin5 is Reset, but Pin6 is something called VSNS: When I test pin6 on both UB10 and 11, it only drops to 3.9V with...
  8. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    Setting aside the clock signals for the moment, I moved on to the Reset circuit, I definitely have an issue here: UB11 pin5 is fine but pin6 only drops to about 4V, never goes full 0V - 0.80Mv. RP7 pin2 stays at 5V. This seems like the most significant issue I've found so far. Need to figure...
  9. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    The 'main' Xtal has 31.334 MHz written on it, that and the C16M 16.667 Mhz clock is perfectly in speed with the guide. I'm having trouble with 3.9MHz specifically. Y1 and Y2 are also part of the clock signals? How are the clocks divided in to the slower speeds? Thanks. EDIT: Setup my scope...
  10. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    Are there more crystals than the largest rectangular one? How would I confirm the C3M clock is having problems in this case?
  11. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    Where is that exactly, and how would I check it? Thanks!
  12. GreenBar0n

    (2) Macintosh SE/30's - Full Restoration

    Hi all, Really glad to have found this forum recently and specifically the Simasima Repair Guide posted here, much thanks for that! I purchased this SE/30 around this same time last year and recapped every board in the unit, also removed UE10 and reinstalled it, fixing all of the broken...