• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

My "hack" IIx is working!

zuiko21

Well-known member
Hi all,

As part of a deal, I got a Mac IIx mobo... after washing the board, I powered it from an old, vulgar ATX 150W PSU -- just the +5V, +12V and GND lines, didn't bother with the -12V line!

First attempt, with the ROM SIMM but no RAM or disks... and the Chimes of Death came out from the connected headphones, if a bit weak -- it's alive!

Second attempt, with 4x 1 MB SIMMs, no disks and an 8•24 card -- standard bong, pattern, pointer and, after a few seconds, the floppy icon with blinking question mark... yeah!

Third attempt, I hang (literally) a Quantum LPS 240 -- no difference... then I remember I removed the termination resistor packs from it!

Fourth attempt, with 8 MiB (2 MiB SIMMs weren't recognised) and proper termination...



Other pics of its resurrection on the set. You may spot my (open) SE/30 in the background ;-) If you're brave enough, you may look at a close-up of the power "connector"

Now the challenge is getting on the internet with it...

Cheers,

 

Unknown_K

Well-known member
So you just have the board and nothing else? Are you going to stick it in an ATX case or something?

 

Byrd

Well-known member
Love the hack, and those molex connectors!!

Would you mind posting a close-up of the molex connectors plugged into the motherboard? I'd like to trial a similar thing on my IIfx, which I believe has a bad power supply. Even if not bad, it'll let me rule it out before I tackle diagnosing a failed component on the motherboard.

JB

 

zuiko21

Well-known member
@ Scott: Yes, have an EtherNet card. It works perfectly in a Quadra 700, but becasue of the built-in port, it isn't needed there, so it would be much more useful on the IIx.

@ Unknown_K: I don't know... maybe I could get a toast MacII some day, and put this mobo inside... or something home-brewed!

@ Byrd: Here you are:

5683522455_b3136a88ee_z.jpg.637a3397172a130b493fb6e78eaf519c.jpg


•The rightmost pin (as seen on my picture) is +12V, put the yellow wire from PSU there.

•Pins 2...6 (from right to left) are +5V, the red wire goes on any of them -- it's enough for a brief test, maybe not for 24/7 on a full laden system ;-)

•Pins 7...12 are GROUND -- any black wire from the PSU.

You may like to connect the -12V line, anyway... the blue wire from PSU to the second pin from right @ IIx. I believe the serial ports won't work without it, it's likely the only use of -12V (audio too?)

By the way... if you're using a standard ATX PSU, you have to connect its green wire to ground (black), otherwise it won't start! In my to do list there is placing an inverter between the ¬PWF signal (leftmost pin on my pic) and that green wire, so I get soft power control, as intended.

 

kite210

Well-known member
Haha, that's an amazing way to get it going.

If you're good with woodworking, you could build a temporary case for it, I did the same thing with an old P4 PC.

 

Trash80toHP_Mini

NIGHT STALKER
Very cool! I'll post an old hack to give you one really down & dirty option for encasing a bare MoBo! ;)

Very creative use of the stuff you had on hand, that ConnectorKluge is out there! :approve: Gotta LOVE IT!!!!! :eek:)

edit: it's already posted, check out the PlasticPOS JunkDrawerHack™ in the PExProjRedux thread in Hacks & Development.

 

LC_575

Well-known member
How did you get a modern monitor to sync with the IIx? What NuBus video card are you using?

 

zuiko21

Well-known member
@kite210: I'm terribly clumsy with woodworking... :)

@Trash80toHP_Mini: Thanks! That seems a nice idea.

@bibilit: Merci beaucoup! Unfortunately, classic Macs are very hard to get in Spain... but we're living in a small world nowadays, aren't we? ;-)

@LC_575: I'm using an Apple 8•24 card. The monitor, a dirt cheap 16 in. Acer, syncs fine from 640x480 to 1152x870, even at 75 Hz -- panel is 1366x768, though. And with several Mac-to-VGA adapters at home, connecting it was fairly easy. Never had a monitor capable of 512x384, though.

Now I'm a bit busy and have this project temporarily stopped... and then there's the SE/30's SCSI repair pending... but anyway the Quadra 700 is getting daily use -- for games ;-)

Cheers,

 

zuiko21

Well-known member
Wow, it's been a long time... but I'm back to this project!

@ bibilit: old Mac are indeed very rare in Spain. I got my SE/30 from UK... like my recent Colour Classic. And my second SE/30 from Germany ;)

In the meanwhile, I purchased a beautiful, working IIfx PSU -- I understand that they're all compatible, but this one has the variable fan for quieter operation.

Then, I ran into a "non-powering" Mac II -- I was about to ask the seller to remove the supposedly dead PSU in order to save some shipping weight -- I was after the bo, after all. But eventually didn't bother...

I received the item, plugged it in, hooked my external SCSI boot disk (the machine came without HD, as advertised) and then connected a battery between GND and /PWF. Guess what happened? It booted perfectly! Sound was very weak, so recapping is soon to be needed, but this was a nice surprise. An e-Machines video card was inside, too.

Anyway, I prefer the performance of the IIx board and VM support, so that will go into this box with my IIfx PSU... and the Mac II mobo will be the "hack" from now on.

More news soon...

 
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