Hello, and welcome back!
I've got these three, fairly rare pieces of Commodore equipment and I'm going to
using these in an upcoming episode of Commodore history.
But, before I can do that, I've got to get them working!
And so here's the deal.
This 1570 disk drive, I actually bought this from Italy and it was actually listed as unknown
condition.
So, don't know if it works or not.
This unit here, was donated to me from somebody in Europe recently.
And I think they said it was working, but it did suffer some shipping damage so, again,
not sure if it's still working.
This unit here, I actually bought myself on eBay from somebody in Hungary and it was actually
listed as not working, but because it was so rare, it was the only one I could find.
So here's the other problem.
This unit here, of course, its from Europe, its PAL, right?
So, I don't have any monitors here in the United States that would do PAL.
I mean, sure I could probably plug it into a modern television or a video capture card
and I could probably get some video out of it, if assuming it was working, but I want
to be able to plug it in to my regular Commodore monitors, so I think I may convert it to NTSC.
And as for these two guys.
Well, they both have internal power supplies and they want 240 volts.
Well, we don't have 240 volts here in the United States, so I'm going to see if I
can convert these to run on 120 volts.
So, let's dig right in.
I thought it might be a good idea to setup my working Commodore 16 to test the two disk
drives.
I thought what I could do is use this voltage transformer to step up up the voltage to 240
and connect the disk drive power cable to it.
After all, the plug on the disk drive is the standard 3-prong connection.
So, then I'd just need the serial cable.
And here goes nothing.
Well, that's a good sign.
Both LEDs came on and the red one went back off.
I guess I should remove this cardboard transport protector, I forgot that was still in there.
And here's a floppy disk with some stuff on it.
All right, so I'll just try to load a directory from device 8.
The drive came to life, and it does look as if it loaded it.
Yeah, there's the directory.
I'd say this drive works fine.
I guess I'll try the 1551 drive next.
Now this drive is quite a bit different from most Commodore disk drives.
It actually plugs directly into the cartridge port of the computer for additional speed.
OK, let's fire it up.
That sounds terrible.
Listen to that up close.
It sounds bad, but I've actually heard worse that still ended up working.
So let's try it.
Ok, that's not a good sign.
However, it occurred to me that somebody might have coded this drive to device 9 and the
directory command always defaults to device 8.
So let's try this.
Hey.. that's interesting.
It's actually trying to load, but in the end it fails to find anything on the disk
and you can see the error light flashing on the drive.
So I think we have a mechanical problem with this drive.
Which, is not surprising considering the condition this thing arrived in after shipping.
You can see the damage here, and when I pick up the drive you can hear all sorts of loose
stuff inside.
OK, so the last thing I'll test is the C116.
I realize this monitor won't support PAL, but I hoped I'd see at least something on
the screen.
Sometimes these Commodore monitors will display a PAL signal in black and white.
Unfortunately, no luck with this one.
Even the little power LED doesn't light up.
So this will require some troubleshooting.
OK, so this is the next piece of the puzzle.
This is a regular 1541 drive I got from The Obsolete Geek.
And it's got some cosmetic issues like this ugly mod, and the top is all yellowed, or
really I guess you could saw browned.
And it's roughed up all over the place.
But the drive itself actually works.
So, what I'm going to do is use this as a donor drive.
Now, all Commodore drives of this form factor come apart exactly the same way.
There are just 4 main screws at each corner.
Then you can flip it over and the top will come off, like so.
You'll want to remove this RF shield and it's just two screws on the side that will
release it.
Next, I'll unplug these wires.
This first one is the front power Led, these next three actually control the various motors
and stuff in the drive mechanism.
This last one is the actual read/write head on the drive.
Then, if you turn the drive around, there is one more wire connection and this is the
power coming from the main transformer.
The logic board itself has 5 screws on top, and then you can turn it over to the side
and there are two more on this heat sink.
Then the board should lift right off.
OK, now we can see the transformer.
This is essentially the part I need to transplant that will change the input voltage on my other
drives to 120V.
However, to get it out, I will need to remove a few more screws down in this section which
hold the frame into the bottom case.
And so, I'll just take those out, and then the frame should lift right out.
On the bottom of the frame are just for big screws that hold down the transformer.
However, this is where I realize another problem.
At first I thought I'd just change out the transformer.
And I could certainly do that, but I'd need to also remove this, this and this.
It's possible the wires will come off, but they are not wanting to budge, so it occurred
to me it might actually be easier just to remove the drive mechanism and keep the transformer
with the frame.
The drive mechanism is easy to remove at this point.
There are just 4 screws and then it comes right out.
OK, so I wanted to give you a little bit more clear explanation of what it is I'm actually
going to be doing here.
So, these three parts here, this logic board, this frame along with the transformer in it,
and this drive mechanism here are the three parts that I have scavenged from the ugly
1541 disk drive.
And here's where they're going to go.
So, I'm going to transplant this entire frame and transformer into this European model
1570 disk drive.
They should be compatible and that should convert this disk drive to work with US voltages.
And then, I need to do the same thing to this one, and I've got another transformer I'm
going to be getting out of another dead drive later, but because I think the drive mechanism
is screwed up in there, due to shipping damage, I'm going to transplant this working drive
mechanism in there.
It should also be compatible.
And then you may be wondering what I'm going to do with this logic board.
Well, I also have this other disk drive here, which I didn't show you earlier and this
is just a regular US model 1541 C disk drive and all it is basically the exact same disk
drive as the one I just took apart, the only difference is they changed the outside color
on it to match the Commodore 64 back around 1985 or 86 when they updated the case style
of the 64 to a white Commodore 64, so basically, exact same drive just different color.
It just so happens this is the only one of these I have and it's actually missing a
logic board.
So, I'm going to put this logic board in there and that will get this guy fixed up
too.
So, hopefully, it's clear where I'm going with all of this.
That one disk drive while it has sacrificed it's life, but it's not sacrificed in
vein because it's going to be used to fix three other disk drives.
So, I think that's a worthy cause.
OK, so here are the 3 drives I'm going to be working on.
I've already removed the screws for the top covers.
And this one here has no logic board.
So I'll go ahead and take care of that, since it's the easiest of the jobs to do.
OK, so now that all 3 drives have boards I thought we could take a closer comparison.
This is just the standard 1541 board like the vast majority of Commodore disk drives
have.
However, this one here is the very rare 1570 disk drive, and the board is quite different.
But the one I find most fascinating is the 1551 disk drive.
And the reason is because all other Commodore disk drives use a 6502 processor inside, but
this disk drive actually uses a 6510 processor, which is the same one used in the Commodore
64.
Neat.
Next, I'm going to go ahead and put this one back together.
But one thing that's still bothering me are these rubber feet.
The rubber has disintegrated.
It could be from age, or could be that too much weight was stored on top of this thing
for a long period.
Once the feet are removed, there's still adhesive down in these holes.
I'll just use some alcohol to clean it up.
In a case like this, sometimes it helps to get creative in order to get all of it cleaned
out.
And that worked well, so now I can replace the feet with these I bought at the hardware
store.
Sure, these aren't the same color as the originals but they will work fine.
All right, so the next thing I need to do is basically take this logic board and this
drive mechanism and transplant it onto this.
But before I do that, I want to verify some voltages here.
Right now I have this unit hooked up to 240 volts using that power transformer I used
to test with earlier.
I'm going to set my meter to alternating current because I'm going to measure the
power coming straight out of this transformer and see what it is.
It won't have been converted to DC yet.
And it looks like I'm getting around 15 volts on one set of wires and around 6 volts
on the other.
So now what I'm going to do is check the voltages on my American version transformer
here, which is hooked up to 120V.
And looks like I'm getting around 17 volts and 9 volts.
Hmm..
Well, hopefully that's close enough.
This little board here, it's whole purpose in life is to convert that power from AC to
DC and then regulate it down to 5 volts and 12 volts.
So now that I've mounted that board, I'm going to check the output here.
This is where the regulated power is delivered to the logic board.
And I am indeed getting a nice regulated 5 volts here, and on the next pins I'm getting
12 volts.
So this looks good.
Now I can remove this logic board and transplant it over.
One thing I want to draw your attention to is that this board is essentially fitted to
the frame with some sort of adapter plate.
And the reason for this is that the board was not originally designed to go in this
case.
In fact, here's a bit of trivia for you.
These boards were designed for the case of the 1571 disk drive, but when Commodore encountered
a shortage of some of the components, they adapted the board to fit in this traditional
style case.
And so that's the reason behind this design.
All right, so I have no transferred everything from there over to here.
And now I'm about to fire it up and see what happens.
That's a good sign.
This LED stays on, which is the power indicator.
And this light came on and went back off, which means it completed its self test.
So now I can replace the cover.
But there's still one issue that bugs me.
The back of the drive still says that it uses 240 volts.
So, I've printed out a new label with the correct voltage.
And while it's not a 100% match, it's certainly good enough to get the job done.
Next order of business is to get the parts from this 1551 disk drive moved over to the
new 120V chassis with properly working drive mechanism.
And I wanted mention something I noticed after I took this thing apart.
There's this little switch.
It has two positions, either in or out.
And it appears to be an aftermarket addition and I quickly realized it was soldered to
the device number selection jumper.
So that explains why the drive was configured as device 9 and it appears that all I needed
to do was click this switch to set it back to device 8.
But I want to do something about this broken plastic.
I mean, that's really irritating.
And here's all of the pieces I found inside the disk drive.
I thought about super glue, but decided to use this instead.
The main reason being I knew it would be really difficult to get everything in place in the
amount of time superglue gives you before it cures.
And this stuff gives me 15 minutes, although in my experience it's more like 5 minutes
to work with.
Still, better than superglue.
Unfortunately, it was too difficult to attempt to film this while working on it, so here's
how it came out.
The epoxy is still a little wet here, but I'd say this is going to look a lot better
than a giant hole.
Since there are a lot of what-ifs with this project, I wanted to test it before re-assembling
everything.
And the good news is, it does work.
So I will re-assemble the drive.
And also give it a good cleaning.
And the last thing I'll be working on in this episode is this apparently dead Commodore
116.
While these systems are very rare, fortunately, all of the chips are the same inside this
working Commodore 16, so I should be able to use this to help troubleshoot the problem.
However, being that the power LED doesn't even turn on, I think the problem may be more
basic than a burned out chip.
OK, looks like we need to remove this RF shield.
On the bright side, all of the chips appear to be socketed, so that is good news.
I'm going to pull out this fuse and test it.
Looking at it, it's hard to say if it is blown or not, so I'll check with the meter.
Sure enough, there's no continuity.
While my eyes may not be able to see the break, the camera's zoom is good enough to show
it.
The most likely cause of a fuse being blown is probably somebody plugged in the wrong
power adapter.
The Commodore 16 and 116 both use a barrel jack with center negative polarity, which
is far less common.
So somebody probably plugged in a power adapter that fit, but was the wrong polarity or voltage
or both, and pop.
Since I don't have a replacement fuse handy, I'm going to do something stupid, which
is just jump this fuse holder with alligator clips.
By doing this, I could cause further damage to the computer, but I'm about 95% certain
there is no short anywhere.
Well, let's see what it does.
Hey, it's working!
This may not look like it's working, but this is exactly what I'd expect to see for
a PAL computer connected to an NTSC monitor.
I took a trip to the auto parts store and did manage to find an exact replacement in
this variety pack here.
Unfortunately there's only one, the others are all the wrong value.
So, I'll just go ahead and stick that in there.
So, to convert this unit from PAL to NTSC I just need to change the kernal ROM and clock
crystal.
I'm getting the ROM from an old C16 that has been in a flood and doesn't work.
I want to try powering it on like this, with just the ROM.
I don't expect it to work, but it's just one of those things I'm curious about.
Neat.
OK, so next I need to remove this clock crystal.
I'm going to try to de-solder it from behind.
You'll notice many of these solder joints are corroded from water damage.
Sometimes solder wick works well for this sort of thing, and sometimes it doesn't.
This is one of those times it doesn't.
So, I'll try another route.
I'll just melt this part here which is holding it to the board.
Then I'll just try pulling the thing out one lead at a time as I heat them up.
And that worked out just fine.
So this thing is a bit ugly due to the water damage, but I suspect it still works.
OK, so the new crystal is in place, let's see what happens.
Hey, it works!
However, I discovered a new problem.
Yeah, half the keys don't work.
And the ones that do work require a lot of pressure.
I unplugged the keyboard and had a look, but this would be very difficult to remove, and
there are no screws to take the board apart.
Rather than reinvent the wheel, I googled this and saw some photos of the keyboard taken
apart, and as I suspected you have to break it in order to get it apart.
But it can be fixed.
It will probably require painting new conductive material on this like I had to do with the
PET.
Well, that sounds like a project for a later video.
Still, I'm glad I managed to make a lot of progress this last few days getting these
drives to work.
And also getting this computer at least partially working.
Again, this episode was not planned, this was another one of those like the PC Junior
episode where I just needed to get this stuff fixed for an upcoming video that is planned.
But, I thought you guys might enjoy seeing the process of how I fixed these things up.
Also, I am really excited about doing the video on this computer because actually I
think it's one of the most fascinating computers in Commodore's history even though it was
a complete failure.
And so I'm looking forward to presenting that and I guess that wraps it up for now,
so thanks for watching.
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