SE/30 no boot

Kepler64Bit

New member
Bought my first SE/30 a month or so ago. No display or chime when I first tried turning it on, but I could hear the fan and hard drive spin up and seek from time to time
Checked the 5V and 12V rail on the hard drive molex, 4.92V and 11.89V
Bought replacement capacitors off of Console5 for the main board and just recently soldered them in place. Still no boot. Took the ROM out and I get zebra lines. Came with two sets of 4x1mb sticks for a total of 8mb, (I think) so I tried each set individually in bank A but no change
Also, nothing happens when I turn it on for the first time, I have to turn it on then turn it off and quickly back on and then it'll show the zebra lines when the ROM isn't installed. Installed the ROM-inator II, no boot but the CRT briefly flickers or shows a bright white vertical line for a very quick moment on the top half of the screen on the second power on before disappearing
The oscillator at Y1 shows ~32kHz, and I'm not sure where to probe to measure Y2, but Y3 just reads 0.000khz (sometimes 0L)
Also, the PRAM battery has been replaced with a coin cell replacement. There's trace amounts of blue stuff on the legs of some of the IC near the group of 6 capacitors (1 axial, 5 SMDs) but it doesn't look catastrophic (but I can't tell for sure)
Reset and interrupt buttons don't have any visible effect
What do I try next? Replace the oscillator at Y3 and go from there?
IMG_2366.png
 

Kepler64Bit

New member
Adding to my own thread, I looked over this oscillator can and to me it looks like it should be a good replacement for Y3 if it is at fault (I believe it is) if I just bend the legs a little, perhaps, but posting it here too just to see if anyone has any input? I feel like I remember someone recommending a 20 or 22pf oscillator, but a schematic I found there are two 33pf capacitors, one on each leg, so I feel like I should get a 33pf oscillator.
 

adespoton

Well-known member
Adding to my own thread, I looked over this oscillator can and to me it looks like it should be a good replacement for Y3 if it is at fault (I believe it is) if I just bend the legs a little, perhaps, but posting it here too just to see if anyone has any input? I feel like I remember someone recommending a 20 or 22pf oscillator, but a schematic I found there are two 33pf capacitors, one on each leg, so I feel like I should get a 33pf oscillator.
Don't take me as the authority here, but in previous oscillator discussions, people have stated that Apple tends to overspec and there's a lot of wiggle room. Probably any of the above would work. Might be worth doing a search for 20, 22 and 33pf in the forums to see exactly what the statements are that were made in the past.
 
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