Macintosh SE Restoration and SD-2-SCSI upgrade

I recently picked up this old Macintosh SE
for $10. It’s pretty yellow, dirty, and has quite
a few scuffs on it. But for $10 I can hardly complain. So the first thing I wanted to do was plug
it in, power on, and perform what we sometimes call the smoke test. Well, I was pleasantly surprised that it did
power on and displayed in image on the screen. No smoke. Don’t worry, the screen had a solid image
on it, my camera’s refresh rate was playing havoc with the recording here. However, it appeared the hard drive was dead,
and I also couldn’t get it to boot from floppy. So, I’m going to completely tear this thing
down and do a full restoration on the computer. And while I’m at it, I’m going to replace
the original SCSI hard drav with this. It’s an SD to SCSI adapter, which is basically
an emulator that emulates a SCSI drive, only it stores the information on a modern storage
device, an SD card. This is going to make the computer quieter,
faster, more reliable. But the most important thing is it will easily
allow me to transfer games and software from the modern world of the internet over
to the old Mac. The first thing you’ll need to take apart
one of these old compact Macs is a special screwdriver, I often call them the “Mac
Cracker.” It’s a essentially just a very long T15
Torx driver. I always put down a towel when working on
stuff like this, to avoid scratching up the face. And here’s where the Mac Cracker comes in
handy. There are two screws under the handle, and
two more screws on the back. OK, so let’s lift the back off and take
a look. OK, so here’s what we have to disassemble
now. I did watch EEVBlog’s disassembly of the
Macintosh SE. Now I’m not sure if this one actually works,
it is supposed to so we’ll find out after the teardown. However, he only took out the logic board. I am going to take it completely apart so
that I can retrobrite the plastics. There are some cables to unplug for the disk
drive and hard drive. However, this particular cable is hard to
reach. But I found that if I removed this back plate
first, that made it a lot easier to reach. I was going to slide out the logic board,
but I realized somebody never put it in correctly last time somebody had it apart. You see, it’s supposed to slide down these
grooves here. OK, so here’s the board and it is quite
dusty. I’ll need to clean this off. But hey, take a look at this. The battery hasn’t leaked, and I’m quite
gratefull about that. So the battery has a date of 1989 on it, I
don’t know if that is the manufacture date or expiration date. Anyway, I ordered a new one on ebay for $8. So let’s take a look at the logic board. It’s a surprisingly simple board. Let’s have a look at what makes it tick. So for starters, this HUGE chip here is the
Motorola 68000 microprocessor. This is the same processor that was used in
the Amiga, Atari ST, and even the old Sun workstations. These two chips are the high and low system
ROMs. This is the PDS slot which allowed various
expansion cards to be connected, including an ethernet card which I really wish I had. This is a VIA chip, or versatile interface
adapter. It basically gives the processor some general
purpose input/output lines. This is a SCSI controller chip, which handles
the hard drive and any external SCSI devices. This is called a SWIM, which stands for Super
Woz Integrated Machine. It controls the floppy drive. This is called the BBU, which stands for Bob
Bailey Unit. It does many things, including video generation. This is the serial controller chip, which
handles the serial ports on the back. These, of course, are the RAM modules Oh,
and this tiny little chip here is the sound chip. It’s very basic, so it doesn’t do much. So, back to disassembly. I’m removing this entire bracket, which
holds the hard drive and floppy drive. I am taking care to avoid the high voltage
components since this thing could still have a charge on it. So here’s what I pulled out. Yikes! Look how dusty that is. No wonder the floppy doesn’t work. So here’s the hard drive, we won’t be
needing this anymore, thank goodness. So I’ll definitely be taking the floppy
out of this bracket too so that I can clean it up, maybe get it working. OK, so now I’m going to deal with the CRT. Now, I know some people get freaked out at
the thought of dealing with a CRT. And perhaps that is for good reason because
you can kill yourself on these things, although it’s not terribly common, it does happen. And the thing is, if you know what you’re
doing and you take proper precautions, it’s relatively safe. Now, want to talk a little about how electric
shocks work. Remember that electricity always takes the
easiest route. So if you were to stick your arm in the machine
and the positive touched you here, and the negative touched you here, it’s going to
hurt, but its probably not going to kill you. On the other hand, if you are using both hands,
and the current travels across your body, and of course your heart, that is where really
bad things can happen. So obviously we want to discharge the CRT
before we go any further. So just attach an alligator clip to the ground
lug of the CRT. Then attach the other end to a long flat tip
screwdriver. Then you just insert the screwdriver under
this rubber suction cup and touch the metal clips. If it sparks, you know you’ve discharged
it. In my case, it didn’t spark so the bleeder
resistor had already done its job and discharged it over the last hour while I was working
on it. So, eventually you want to pop the suction
cup off. Then you can lift this little board right
off the back. It connects exactly like an old vacuum tube. These wires here control the magnets on the
tube, and they need to be unplugged. Ok, next order of business is to remove the
analog board. There are two screws up here and two more
down here, plus one over here for the ground wire. Then you can carefully lift the board out
of the machine. There are 4 large screws holding the CRT to
the machine. You need to remove those with the torx driver. Then you can lift the tube right out of the
machine. All that is left now are 5 screws holding
the chassis to the front panel. So, there we have it. The front cover to the Mac. But, we still have to deal with this speaker. Unfortunately, they melted plastic in order
to hold the speaker on. So I’ll have to cut this plastic in order
to get the speaker out. And there we have it. So, now we can move on to the cleaning phase. I always want to use the spray especially
to clean out all fo the vents and crevasses on the machine. I always clean pretty much every part that
I took out of the machine, no matter how trivial it seems. Although granted, I pay a lot more attention
to the exterior case pieces. It’s very important to get this super clean. And while the retrobrite is an important step,
I think a lot of people neglect the all important process of hard scrubbing to get all of the
marks and imperfections cleaned. Sometimes these marks seem permanent but there
is almost always some way to get them off if you are willing to put the work into it. Sometimes I find it easier to put the pieces
in my lap where it is easier to work on them. OK, now it is time to lay the plastic out
for the retrobrite process. I always use a paintbrush to make sure I get
every part of the surface coated in the hydrogen peroxide solution. I also spread it out evenly on the plastic
wrap too. Then I fold it all up and make sure it is
more or less air tight. Then I take it out to sit in the sun for a
few hours. The larger case piece proved to be somewhat
more challenging, as it required quite a few extra pieces of plastic wrap. I had to coat it in stages and overlap the
plastic wrap. But it wasn’t hard. I brought it out to set next to its sister
piece. I ended up leaving these in the sun for about
4 hours. Every 30 minutes I would come out and rotate
the pieces for even exposure. I also massaged the cream around inside the
plastic wrap each time as well. While waiting on that, I turned my attention
to the floppy drive. I cleaned it out with compressed air. Then I used alcohol and cleaned the read heads. I also re-lubricated many of the parts where
the grease had dried up. I also got to work on building an adapter
plate. OK. So what I need to do now is figure out how
to mount this nicely in there. In fact, if I look at the original hard drive,
and line up the screw holes, it lines up about right there. So, if I wanted to be accurate, actually it
looks like this needs to be flipped around. And I have to be able to mount it. I need to be able to mount it about right
there. So I grabbed a piece of sheet aluminum I had
laying around, and I used the original hard drive as a template. I took it outside and used my dremel to cut
the piece out. Once I got it out, I used a file to smooth
those sharp, jagged edges. My wife used one of her little tools to stamp
out the line where it needs to be bent, this will make it easier to bend exactly where
we need. That worked out pretty well, so I drew my
holes using the original bracket as a template. So I put this vinyl tape on here. It’s not really necessary, but it makes
me feel better and you’ll see why later. I also wanted to be able to operate the front
LED on the Macintosh, so I had to add a little 2-prong header onto the board and solder it
on. Here’s what it looks like and you can see
how it connects to the LED now. So 4 hours have passed and the sun is starting
to set anyway. So I decided it was time to unwrap the plastics
and rinse them off. And here are the finished case pieces. You can see this looks fantastic now! Next it was time for dealing with this speaker. Since there are no screws and I had to remove
the plastic holding it on, I had to use some epoxy to secure it back in place. I had to actually let this cure overnight
before I could mess with it any further. However, the next morning it seemed to be
held in place quite nicely. So I reassembled the computer with just enough
parts to make sure everything is still working after my cleaning. At first it didn’t appear to be working,
but then I realized I needed to check the brightness control since I had been messing
with that during cleaning. And there’s the picture, looks like it is
still working. I wanted to see if it would boot from a floppy
now. But, unfortunately, it would not. The drive just moves around, but it can’t
seem to read the disk. I also noticed it was making a bad noise when
it tried to eject. I pulled the ejector mechanism apart and discovered
some broken teeth on these plastic gears. I tried booting from an external floppy, but
that didn’t seem to work either. I think the external is a low density and
my boot disks are high density. So I snagged the floppy drive from my old
Macintosh Plus. It sits on my shelf and looks cool, but otherwise
I’ve never been able to get it to work. The downside is that it is only a low density
drive. I got in the new battery so I went ahead and
swapped that out. I also left this blank open on the back with
the USB cable hanging out, this way I can update the firmware or even read and write
data to the SD card using a modern computer. If this works, I’ll come back later and
buy one of these panel mount USB connectors and mount it in this spare plate so it will
look nice. Nevertheless the computer will boot with the
low density drive and now I’m able to try initializing my emulated hard drive on the
SD card. I have the HDSC program on a second floppy
using an external drive. It requires a modified version of this software
because the version that Apple supplied back during this time will only recognize apple
branded SCSI drives. However, I’ve used this patched version
on many generic drives in the past and never had an issue with it. Well, here goes. Looks like the LED I wired up is working. However, I kept getting this error message
when it tried to write to the disk. Well, like always, these sort of projects
don’t always go to plan. So, I’ve got the Macintosh SE more or less
completely restored and functioning now, but as you can see, I can’t get the SD-2-SCSI
device to work. Now, a lot of people have had good luck using
the SD-2-SCSI device on their old Macs. But I can’t find any evidence that anyone
has ever tried it on a Macintosh SE model. So, I’ve been going back and forth with
the creator of the SD-2-SCSI device and I’ve sent him some log files and he’s sent me
some custom firmwares to try, and nothing has worked. But, the question has been raised – we don’t
know for sure if the SCSI controller in this Mac is working correctly. After all, when I got it, it wouldn’t boot
from the hard drive to begin with. So, I’ve never confirmed that that works. So there’s one of two problems. Problem 1 is the SD-2-SCSI device is simply
incompatible with this model. That may be something we just have to live
with. I may have to use it on a different device. Problem number 2 could be there is something
wrong with this machine. The only way to really troubleshoot that is
to get my hands on another Macintosh SE. Well, I just happen to know somebody in town
who owns one. The Obsolete Geek did an episode a while back
about installing a SCSI emulator device in his Macintosh SE, which is really similar
to the device I have except his is a different brand and uses compact flash instead of SD
cards. Well, he just lives across town so I asked
him if I could borrow his for some troubleshooting. And so, the Obsolete Geek did, in fact, loan
me his Macintosh SE. Now, you can tell his is not in nearly as
good of shape as mine is after the complete restore. But hey, his works! So, I’m going to start taking it apart and
take this one apart, and we’re going to swap some parts and find out what’s going
on. So I have the two torn apart and I put my
SD-2-SCSI device connected to Rob’s Mac. So I’m booting his up. Now you can see his has this accelerator logo,
which I’ll talk more about that later. So here we are and I’m about to find out
if this device is going to work in a Macintosh SE. Well, it didn’t even give an error, it just
locked up completely. So I think we can assume this device is not
going to work. But, I still wanted to confirm that my Macintosh
SE was actually working, so I took his hard drive emulator and connected it to to my Mac
and tried to initialize a fresh flash card. Well, my Mac ended up locking up on his device
too. So now I’m back to square one. But keep in mind these units aren’t entirely
identical. Rob’s Mac has this accelerator card on the
logic board which changes things quite a bit. And I suppose there is always this possibility
that my software disk has a problem. So, in one last ditch effort, I used Apple
Pi Baker in order to copy a working hard drive image that somebody sent me from another Macintosh
SE, to see if I could get it to boot directly from the SD card without having to actually
install the operating system on there. And, to my amazement it did actually boot
part of the way up, but it would always lock up at some point during the boot process. I tried this several times, so apparently
this was a no-go as well. But, it does prove that the card is at least
somewhat operational with the computer. So, I think we’ve come to the end of this
project for the time being. I still don’t know 100% sure if the SCSI
bus in this computer is working correctly or not. And the only way I’m probably going to find
out at this point is to buy or find an original SCSI drive, and I know somebody who’s got
one and I’m going to try to arrange that later next week. In the meantime, I wanted to mention that
it’s still not a total failure. While it’s unfortunate that I didn’t get
the SD-2-SCSI device working, the machine is otherwise perfectly operational. And you can use these things without a hard
drive. You can run quite a few old games and stuff
on just the floppy drive. It’s just not nearly as convenient, and
the main problem is getting software over to these double density floppy disks. It’s really a pain because the modern USB
floppy drives won’t write to these. There is another alternative, by the way. There’s another product out there that will
emulate a Macintosh floppy drive. And one of the neat things about that, besides
the fact that you can copy a whole bunch of different disk images over to this device,
but it can also emulate an external hard drive using the floppy port, because Apple actually
did make some external hard drives that plugged into the floppy port. So it wouldn’t be as fast as an internal
SCSI drive, but it would certainly work, so even if the SCSI bus in this thing is not
working, that’s still an alternative that it could use. Oh, and another thing is, according to the
website with this product, it has been tested on the Macintosh SE/30. Which, that is the compact Mac I’ve always
wanted, because that was like the best black and white compact Mac they ever made. And so if I ever get my hands on an SE/30,
then I’m going to put this inside of it. As always, I hope you enjoyed this adventure,
and stick around because I’ve got more adventures coming up!

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