Phipli
Well-known member
12.7v and 5v is fine. The 5v is the important one and the 12v always seems a little high.
Don't bother recapping, they generally don't need it.
One of the reasons SEs are great.
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Mystical Macintosh SE connector on the back
- Thread starter 8bitbubsy
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Don't bother recapping, they generally don't need it.
One of the reasons SEs are great.
8bitbubsy
Well-known member
I know, but this machine is from 1987 (there was even personal files on the disk from 1987). Electrolytic caps dry up and the rubber seal disintegrates over time, it's still a good idea to recap it even if it's not of the dreaded '88-'94 SMD capacitor type.
These kind of consumer grade capacitors are not made to last this long.
Especially the capacitors in the secondary section of the PSU (or any switching mode PSU) can be a subject to stress over time.
These kind of consumer grade capacitors are not made to last this long.
Especially the capacitors in the secondary section of the PSU (or any switching mode PSU) can be a subject to stress over time.
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That's relative of course, pretty much all outlasted the useful life expectancy of the computer by a decent margin!
Don't imagine they designed the compacts and said, well let's make sure they'll still be working well into the 2020's
Phipli
Well-known member
Thats weird, case serial number says it was manufactured in the third week of 1988. I think the files were created on another computer and moved onto this one.
But yeah, fair enough, I usually do condition based repair on these, although economies of scale with min orders and shipping meant I did all the family's compact PSUs in one go.
8bitbubsy
Well-known member
Ah, I see. 1988 is still old for consumer grade electrolytic capacitors.
And while the voltages and stability may seem fine, the ripple levels of the voltage rails may not be that optimal because of aged caps.
8bitbubsy
Well-known member
Hm... Having some issues. I installed a BlueSCSI v2 Desktop with its latest firmware, and I made a 1GB disk image on ID0.
I made some System 6.0.7 Norwegian 800K floppies, booted the Utilities 1 disk to partition the drive with Apple HD SC Setup.
Installed the OS, and when I reboot, it says that the system file on this disk is broken. I tried to delete the system folder and reinstall System 6 - same issue...
Any suggestions? I also tried to remove the 68030 accelerator, same issue.
I made some System 6.0.7 Norwegian 800K floppies, booted the Utilities 1 disk to partition the drive with Apple HD SC Setup.
Installed the OS, and when I reboot, it says that the system file on this disk is broken. I tried to delete the system folder and reinstall System 6 - same issue...
Any suggestions? I also tried to remove the 68030 accelerator, same issue.
I have a few V2's lying around, but haven't used them yet, so only experience with the BlueSCSI v1.
I tend to use Basilisk II on a modern PC, works both ways, I can check that the image on de SD card boots correctly (like when in your case you have installed an OS on it the "classic" way), or I can install directly an OS on an empty image, and then move it over to the SD card to be put in the BlueSCSI.
Biggest advantage is that you immediately can rule out an issue with the image on the SD card, narrows down the area to go looking for problems!
I tend to use Basilisk II on a modern PC, works both ways, I can check that the image on de SD card boots correctly (like when in your case you have installed an OS on it the "classic" way), or I can install directly an OS on an empty image, and then move it over to the SD card to be put in the BlueSCSI.
Biggest advantage is that you immediately can rule out an issue with the image on the SD card, narrows down the area to go looking for problems!
8bitbubsy
Well-known member
I see, but I want to set it up locally on the machine to make sure everything is optimal. I tried to format it with Apple HD SC Setup instead of partitioning it, now and I got an "address error" crash. I ran a full RAM test on this thing just now, and it passed. Also ran a full disk test with Apple Personal Diagnostics, and it passed too. Maybe BlueSCSI v2 Desktop is not that compatible with Macintosh SE using System 6 Apple HD SC Setup?
I would only want to sell it locally in Norway, sorry. Also it's not like I would sell it for cheap, this thing is probably worth $100. It has 68030 25MHz (compatible with up to 33MHz), 1-waitstate RAM (configured from 2 to 1 waitstates), and onboard video with VRAM.
I'll have a go at it on one of my SE's, as good a reason as any to test my v2 BlueSCSI!
I understand you trying to install the"correct" way, but for troubleshooting purposes, I would try with a bog standard (English) 6.08 image, you can find them online and stick it on an SD card, see if that boots.
If it does, then you know it's not the BlueSCSI or SD card, but rather something with the installation procedure.
Would Belgium be Local enough
? Love to get one of those cards, don't see them much here.Oh, and I guess it's worth well over 100 €!
Phipli
Well-known member
LaPorta
Well-known member
Totally understand the $100 (or more), I’d definitely do that…I didn’t know you were in Norway, though.
cheesestraws
Well-known member
All of this stuff was cost-engineered. It wasn't optimal to start with.
You can replace the electrolytics if you like or if it looks dodgier than usual, but it's probably not strictly necessary - but it mostly sounds like you've decided you want to do it and you're going to do it.
JC8080
Well-known member
What benchmark program did you use? Do you have results from Speedometer 3.x? I'm curious how my Radius 25mhz '020 does against your 25mhz '030.
Phipli
Well-known member
Norton System Info
I don't sorry.
It depends on whether the tests run within the Radius' cache or not. The big difference between the performance of the two cards is that the Radius uses the SE's 16bit, 8MHz RAM (two accesses required for each memory request to fetch a 32bit value), while the Mobius has 32bit RAM @25MHz. This doesn't account for wait cycles. Using RAM specs, the Mobius RAM likely runs about... 84% faster? 70ns, vs stock 120ns is 42%, then half the accesses, because it is 32bit not 16bit.
When the Radius is using its cache, performance will be closer.
Phipli
Well-known member
Correction - stock is 150ns, so performance from RAM is lower than I calculated.
8bitbubsy
Well-known member
Just desoldered ALL the electrolytic caps on the analog board and in the PSU, and measured them. ESR was low, and capacitance was well within tolerance.
Found one 1µF 50v cap in the PSU that had 2 ohm ESR, so I replaced it with a Nichicon (low ESR series) that had 0.5 ohm ESR. Also removed the old thermal paste in the PSU and replaced it with new one.
The people that said that these machines have caps that don't need replacing, weren't kidding. This is pretty impressive.
Found one 1µF 50v cap in the PSU that had 2 ohm ESR, so I replaced it with a Nichicon (low ESR series) that had 0.5 ohm ESR. Also removed the old thermal paste in the PSU and replaced it with new one.
The people that said that these machines have caps that don't need replacing, weren't kidding. This is pretty impressive.
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where in Norway are you located, @8bitbubsy ? Fellow Norwegian 68k-Mac enthusiast here.
