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Macintosh SE/30 M5119 - Restoration

Got confused by the pin count, all the UE10 pins are now connected correctly and not missing anywhere.

Still Simasima and no sound. Will keep going tomorrow.
 
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Went through the clock signals and not sure what to make of this.

SE30 Clocks.jpg
The C16G clock running the same speeds as C16M seems odd since all of the C16M clocks were exact. The E clock is off too.

But the strangest is the C3M clock wave form, when compared to the others, this is C3M running slightly slower than the expected 3.9MHz:
20251222_135743.jpg
C3M looks like a stutter, or overlapping signal, is there something off here?
 
I did setup my scope better, I guess I won't worry about the slightly slower speeds 3.67MHz vs. 3.9 Mhz, all the clocks are where they're supposed to be.
20251222_151854.jpg


I moved on to the Reset portion of the guide and I definitely have a problem here:
Reset Circuit.jpg

UB11 pin6 only drops to about 4V with the Reset.
RP7 pin2 stays at 5V with the Reset.

Would that mean RP7 has gone bad and that may be why UB11 stays partially high?

Thanks!
 
I was measuring RP7 pin7, not Pin2, Pin2 goes to 0V with Reset, RP7 is working correctly, my mistake.


Added sockets for UB10 and 11, the Sony Sound chips, cleaned the board underneath thoroughly.


Souny Sound UB10-11.jpg
I can get Pin5 on both UB10 and 11 to go to 0V with the Reset button, but Pin6 only drops to about 3.9V.

Anyone know what VSNS on Pin6, means or does?
 
Tried the CPU walk the bus test and I can't get a square wave from any of the ROM slots, the wave form is a mess, with varying speeds, nothing is consistent.

Is there any way to tell if a CPU is bad without another one to test with?
 
Going to have to try ordering another CPU, want to replace it with the same I already have.
 

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Found an issue with my Y3 Xtal, and was wondering if this is normal.

On the Y1 Xtal I get a matching wave form on both legs with a clock of 32kHz:
20251226_031520.jpg


20251226_031644.jpg

But on Y3, that is close to the UE10 chip that was corroded badly from the cap leak, I get a strange looking waveform on one of the legs:
20251226_031731.jpg

The good signal from the leg farthest away from UE10:
20251226_031850.jpg

The other leg closest to UE10:
20251226_031916.jpg

When I look at the schematic I see both Y3 legs are attached to UE10, Xtal In and Xtal Out. Should both Y3 wave forms be exactly the same, like Y1 is? Does Y3 go bad?
 
Thanks for that! Y3 seemed good to me too, but I was having some strange clock signals and intermittency with the square waves in the ROM socket, which I'll need to identify where the problem is actually coming from.

I bought another Se/30 that works that will be here late next week, hopefully; I'll use it to compare signals with, which should speed up the troubleshooting process.
 
I have not tried to tighten the pins, I have wiggled the ROM in the slot and never get any change.

Did you have a chime with loose pins, or ever get it to chime in that condition?
 
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