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I shortened my probe ground lead, or got rid of the extension I was using - this green one: And used only the ground lead the probe came with: This made the ringing less on the closest Y3 leg to UE10, which was the really odd pattern before: But now the Y3 leg farthest from UE10 isn't...

I was using a very long ground lead, I'll make it as short as possible and measure again at Y3, UE10 and C33 and C34, to make certain of what I'm seeing here. I'll do this now. Thanks for the reply!

I feel like I keep repeating myself, because I've replied to two different forums, and many threads trying to narrow down where the problem is coming from. A working SE/30 board is hard to come by these days, I'd have to buy a $500+ working SE/30 to get an example to follow. The immediate and...

Wondering if my Y3 has been damaged from a leaking cap. My UE10 had four traces severed, I had to remove UE10 and reinstall it to fix the traces. My Y3 issue looks like this: Leg farthest from UE10: Leg closest to UE10: Should both legs of Y3 be identical in wave form, like Y1 is? No...

Thanks for the detailed explanation. The UB11 Pin6 issue was confusing me greatly, it was the last unknown for the Reset troubleshooting section, that could've still be responsible for the missing square waves from the CPU bus. I should have the new MC68030RC33B next Monday.

So when the Repair guide says Pin6 should be 0V, this is an error in the guide?

S1 is perfect everywhere else and throughout the Simasima Repair Guide, everything works except the Sony Sound chips Pin6. Just so there is no confusion I made this video: Pin5 is 0 - 0.80mV Pin6 never goes much below 3.9, for both UB10 and UB11. Thanks for the help!

This guide was the reason I found this site and joined, well done and thank you for this! I wanted to ask about the Reset section, on page 44, it instructs that UB11 Pin6 should go to 0V. The picture is showing UB10 highlighted on my logic board, instead of UB11 - I can't get UB10 or UB11 Pin6...

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...

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.

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...

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...

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...

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?

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...

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...

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...

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

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

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...