Fat Mac with HyperDrive revived!

[MOS8_030]

After the recent revival of my Lisa 2/5 I decided to drag out the Mac512K with the General Computer HyperDrive.

I picked this up at Goodwill back in the '90's. (1996 if I can believe the file dates on the HD. That's all I have to go on.)

I think I paid $120 for it maybe. (That may be what paid for the Lisa, I just don't remember.)

Interestingly, based on the serial number this system started its life as a 128k but the badging on the back says 512 and it has a 512K MB.

But who knows, maybe the original owner had it upgraded when the HyperDrive was installed.

It was working and I thought it was kinda cool. I knew it must have cost a fortune when it was new.

Anyway, after messing with it a bit I put it away and it's been sitting since '97 or so.

So I pulled it out and tried to fire it up last week. The mac booted up ok but the HD drive wouldn't start up.

Long story short the power supply for the General Computer piggy-back card and the HD was only putting out ~7v or so.

There was nothing visually wrong with it, no leaky caps, etc.

So while I was googling around for info I ran across LuckyBob's forum post here about his Mac Plus with a HyperDrive.

He mentioned using a Meanwell power supply so I got to looking at Meanwell's catalog and after a couple of false starts I discovered that their PT-65B looked like a drop-in replacement for the original Hyperdrive PS.

It was, right down the exact same dimensions!

The only difference was the ground used a spade connector rather than the Molex plug on the input side. The output side pin-outs are the same but flipped.

So after after carefully reassembling everything I held my breath and flipped the switch.

 

[MOS8_030]

And I was rewarded with a chime and a HyperDrive startup screen!

But then it booted up in the Minifinder. (Remember when that was a thing?!)

Huh, that's odd, but then I have no idea what I was doing with the system when I last used it 20 years ago!

Ok, so it took me a few minutes to reactivate the Old Mac part of my brain and figure out how to switch the boot to the Finder.

That being accomplished I started to poke around and see just what was on this thing. All I remember is I put a bunch of games on it.

I checked out the HyperDrive software and ran the disk check utility. No bad blocks or sectors!

 

[MOS8_030]

Browsing through the programs.

Some more HyperDrive tools.

Should I encrypt my HD?  I think not.

Disk Tools II - I vaguely remember this.

Avie Tevanian's Missile Command. No wonder Steve hired him!

The ancient ancestor of Google earth!

The only bad news is the floppy drive won't eject. It works, reads disks fine but won't eject. I cleaned and lubed it while I had the system apart but oh well.

That's probably why the system came with an external drive. It works just fine.

Anyway, that's enough for now. Sorry for the photo dump but I was pretty happy to make this thing work again.

Maybe tomorrow I'll find the software disks I have for this thing, with the 512K apps on them.

I have a ton of old Mac stuff I haven't looked at since the 90's.

After I get this one squared away I think I'll dig out old my Portable and see if it still works!

 

[BadGoldEagle]

Interesting... Mine's saying it can't find the Hyperdrive driver. Could it be that the PSU isn't outputting enough voltage to the daughterboard? Hummm... 

I'll have to recap that Hyperdrive PSU asap.

 

[mactjaap]

Absolutely cool machine! Nice to see so much pictures. A machine which is on my “must have” list!

 

[MOS8_030]

Interesting... Mine's saying it can't find the Hyperdrive driver. Could it be that the PSU isn't outputting enough voltage to the daughterboard? Hummm... 

I'll have to recap that Hyperdrive PSU asap.

Check the voltage output for sure. If it's bad I wouldn't bother trying to repair. The PT65B was only ~$15 +shipping.

Your sig indicates you have the software and manuals, you're lucky, my system came with nothing.

I think I backed up the HyperTools stuff back when I got it just case the hard drive crapped out.

I need to look through my stuff and see if I can find them.

 

[BadGoldEagle]

I have the physical disks but they're either bad or were reformatted... olePigeon and tanaquil backed up some of their disks and uploaded the images to the Mac Garden.

But I think power isn't the only issue. I bought a DOA HD20 a couple of months ago and all I had to do to get it back to life is relube the shaft on the Rodime's stepper motor. I suspect all stepper motor drives need new lubricant at this point. Nearly all MFM drives had those so it's probably a good idea to add a couple drops of oil while I'm at it. But if yours suddenly stops working and throws some error, it might just be that the stepper motor needs a little servicing. 

 

[MOS8_030]

Well it fun while it lasted.

I think Mac PS is bad now. It crashed & died while I was running it today.

Now all get is crackling from the speaker when I turn on the power.

I was reading a bunch of floppies with the external drive so I was pulling some extra power.

It doesn't really surprise me, if the PS for the HyperDrive was bad then the Mac PS will certainly have issues too.

I might try recapping it or I also have a couple of spare PS boards I can try.

But I'm going to set it aside for now while work on the Lisa.

 

[BadGoldEagle]

That was to be expected. Mine’s shot as well. But you can’t just replace it with any other board as GCC modified a couple of things on their Hyperdrive’s Analog board to beef it up a bit. Only solution is to recap and/or repair...

 

[BadGoldEagle]

I made some time ago a list of which caps had to be replaced on mine.

The A/B caps should be the same on yours but I think my Hyperdrive PSU is slightly different. I'm including it anyway for reference.

Hyperdrive PSU (YMMV)

2x 200v 100uF (1,8diamx4height)
2x 35v 1000uF (1,5x2,5)
2x 25V 470uF (1,3x2,2)
2x 10V 2200uF (1,7x2,5)

/* Those are centimeters by the way... */

A/B caps
C1 BP 35V 3.9uF
C2 16V 4700uF
C3 16v 200uf
C4 good
C5 10v 47uf
C6 50v 22uf
C7-C8 good
C9 160v 10uF
C10 good
C11 16v 33uf
C12 good
C13 16v 33uf
C14 50v 22uf
C15-C23 good
C24 16v 2200uf
C25 16v 1000uf
C26 16v 1000uf
C27-C28 good
C29 16v 2200uf
C30 16v 220uf
C31 16v 1000uf
C32-C34 good
C35 200v 100uf
C36 200v 100uf
C37 good
C38 X filter
C39 10v 470uf
C40-C42 good
C43 10v 470uf

*/ The ones marked as "good" are non-electrolytic capacitors and shouldn't need replacing */

Hope this helps.

 

[MOS8_030]

Thank you! That's helpful.

I've already replaced the HyperDrive PS so it's working fine.

I'll have to double check but it looked like to me the only "mods" done to the Mac PS by GC was where the they tapped in the wires for the HD PS.

 

[BadGoldEagle]

They actually used beefier capacitors with a higher voltage rating. What's weird is that the Hyperdrive isn't really supposed to put more stress on the original A/B since it taps its power directly from the switch... But they did upgrade its caps to the same ratings Larry Pina suggests using in his book. Those are supposed to future proof your Mac but 30 years is still 30 years. They're still bound to fail because of old age.

I'll try to recap mine asap and see if it brings it back to life.

 

[MOS8_030]

I have the PDF of Larry Pina's book. Very cool reference. And I have the GC HyperDrive manual.

I'll go over both again when I go to repair the Fat Mac.

 

[MOS8_030]

Ok, the Fat Mac is back, HyperDrive and all.

I replaced all the caps on the analog board along with the flyback, the toasted Q3, and a few crucial diodes.

That revived the Mac but it then it was giving me a Sad Mac and a 0F0100 error when trying to boot from the MFM drive.

I confirmed that the basic system was working and could boot up from a floppy.

I took it apart and found what I thought might be broken traces on the HD card but no, they were just scratched and were still ok.

So wtf, the system was working fine prior to the analog board puking and I know the hard drive didn't go bad just sitting on the bench for two weeks.

Check all the connections, the "killy" clip, etc. etc. all look ok.

So I pulled out floppy backups of the HyperDrive system and tools I made 20+ years ago when I got the system.

But, just then, the floppy drive craps out!

So I check it out and it's got a broken gear in the eject drive, apparently this is a thing that can happen after 30 years.

(And I can get replacement gears. Anyone ever try them?)

No problem, I have a dead spare drive I can scavenge for parts right? Nope, it's in the same condition. Good grief!

Anyway, I was able to dig up a working floppy drive and got the system booted.

Hmm, the HyperDrive tools see the hard drive and I can mount the drawer!

Excellent! The HD is working.

So, to skip to the solution, the system file on the HD must have gotten corrupted when the analog board died.

I reinstalled the HyperDrive driver into the system file on the HD and bam, I can boot from the HD again.

I may yet go ahead an reformat it and install a fresh system file once I get the floppy drive repaired or replaced.

So glad I had some small success today to counter the bad news...

 

[mactjaap]

What a fantastic story to read. I would have waved the white flag with all this bad luck, but you didn’t surrender! 

About the gear. It is replaceable. You can order 3D printed gear. It works but be careful with installing. The wheels are a little bit soft so can be damaged easily. Try to Google for gear Macintosh. If you cannot find it I will look it up. 

 

[MOS8_030]

Thanks, yes this was a bit of a challenge and I probably replaced more components on the analog board than were absolutely necessary, but the parts were relatively cheap.

So now it's just the ancient hard drive that's the weak point.

Yeah, the floppy drives. I seem to be plagued by floppy issues. I still need a drive for my Lisa/XL.

The drive I used came out of an Apple external FD case. I'm going to put it back together when I get the original FD repaired.

I found those floppy gears that are available and I'm probably going to get some.

I was wondering if anyone here has tried them before.

 

[mactjaap]

I fixed one gear with it. But first attempt one gear broke. So I complained and got a new one. So be careful and don’t use to much force. 

 

[MOS8_030]

Hmm, that must be why them offer them in packs of four!

Brittle or not those gears do seem to be the only option if I want to repair my floppy drives.

 

[mactjaap]

You can also use spare gear from other drives. But not the ones with those yellow gears. They all rot away after some time.