1988 Macintosh SuperSE Project: Part 1

My side MARCHintosh project is beginning…

In January, I received two vintage Macintosh computers from a staff member at my university’s library: a 1994 Macintosh PowerBook 165 and a 1988 Macintosh SE. That particular Macintosh SE had a special place in my heart after I saw it on a college tour in high school and again my junior year here at my university.

I re-discovered the 1988 Macintosh SE “SuperSE” when it was located in a display case at our university library.

After getting the machines home, I quickly discovered the SE wasn’t an ordinary SE like the stock 1988 Macintosh SE I’m writing this on. Instead of being powered by the same Motorola 68000 that served as the brain for many early Macs (from the original Macintosh 128k in 1984 to the Macintosh Classic in 1990), this one was special. The previous owner, who purchased both machines as a graduate student in Texas, upgraded the machine with a Mobius 030 accelerator card.

Unlike other Macintosh SE computers, this particular one was hiding a secret inside: a Mobius 030 accelerator card. This allowed users to improve the performance of their machine with a Motorola 68030 processor at 25 MHz, outpacing the processor in the infamous SE/30.

The Mobius card offered enhanced performance that far outpaced that of the stock 68000. It also offered other bonuses – the ability to use an external display (which the previous owner did), and the ability to add additional memory (which they also did – the machine came with 16 MB installed, quadruple the maximum amount a stock SE could accept.)

Because of the expansion card – and to reduce confusion with my other, stock 1988 SE – I coined the “SuperSE” moniker for the computer.

The Mobius 030 accelerator card not only provides improved performance with the ‘030 processor, but also allows for additional memory to be installed, along with external display capabilities.

Although the SuperSE works, it – like all other vintage Macintosh computers – need work to keep it in good, working condition and prevent damage. As with most other computers of its age, the SuperSE is threatened by two issues: the PRAM battery and capacitors.

The former issue can be the most devastating. The PRAM battery can be a ticking time-bomb that can completely annihilate the logic board if it ruptures. Thankfully, I’ve seemed to luck out – the Varta PRAM battery hasn’t leaked yet. (Unlike the stock Varta battery in my stock SE, it no longer keeps the time and date settings.) Because the SE has a soldered PRAM battery, it will be removed and replaced with a fancy battery holder that was found on later Macintosh models like the SE/30 and Classic, allowing for easy installation and replacement of the battery.

Capacitors are another issue that faces these vintage Macs, but to a less devastating extent. The capacitors can – and usually do – leak over time, which will eventually eat away at the printed circuit board underneath. The leaked electrolyte (or “cap goo”) can cause the machine to act erratically or not function at all. I saw the effects first-hand with my 1991 Macintosh Classic. The computer was having strange video issues and refused to boot. The culprit was leaked electrolyte that had damaged part of the board. (Thankfully, it was repaired and didn’t require any jumper wires. However, some people are not as lucky.)

Damaged silkscreen on the Classic’s analog board, caused by leaked electrolyte.

When acquiring a vintage computer (or electronic device), always remove the battery as soon as possible. Later, remove the old capacitors and clean the boards to get rid of any leaked electrolyte. Then, install new capacitors from a reputable manufacturer.

Many opt to do the work themselves. But since I’m horrible at soldering and don’t have the time or space to do the recap myself, I send my boards off to Thomas at Amiga of Rochester for the recap process.

Take Apart

The disassembly process for the Macintosh SE isn’t too dissimilar to that of the Classic. However, there were some added obstacles – some caused by the accelerator card.

The process for opening the SuperSE is the same as my other SE and the Classic: four screws to remove and the bucket simply removes. However, this is where the similarities end.

Since the SuperSE has an internal hard drive and the rear expansion port is populated with the external display connector, space is limited inside. To remove the analog board connector on the logic board, discharging the CRT and removing the neck board is almost necessary.

With an internal hard drive and populated expansion slot, the Macintosh SuperSE is cramped inside.

Removing the logic board on the SuperSE isn’t as easy as removing the logic board from my stock SE. The Mobius 030 accelerator card adds some slight difficulty to sliding the board up and out, although putting it back in is much harder.

With the logic board out of the way, the real work now begins. Since the CRT neck board is already removed, all I need to do is remove the anode cap. Unlike the anode cap on my 1991 Macintosh Classic, this one didn’t put up much of a fight.

What did put up a fight, however, was removing the analog board and power supply assembly from the chassis. It took about ten minutes to get it out. Once out, I separated the Sony power supply from the analog board itself. Both will be receiving the recap treatment.

The analog board/power supply assembly was difficult to remove from the machine.

And viola! All I’m left with, for now, is the chassis, CRT, and the floppy/hard drives. The logic board, analog board, and Sony PSU will all be on their way to New York to be professionally cleaned and recapped.

The empty computer. All that remains is the chassis, CRT, and floppy/hard drives.
Meanwhile, the logic and analog boards were placed in ESD-safe bags for shipping.

Further Plans

While the boards are in New York being recapped, I will be collaborating with a fellow vintage Macintosh enthusiast in the Kansas City area on cleaning and lubricating the 800k/double-density drive. The double-density drive in this machine is dirty and needs lubrication really bad.

After that, I will be cleaning the case. Thankfully, the SuperSE’s plastics are in near-mint condition and have hardly yellowed. There is just one or two scuff marks, and two plastic pieces adhered to the sides.

Lastly, I want to turn my attention to upgrading the storage… externally. The existing Maxtor hard drive still works well – even with its interesting noises. However, I’d like to be able to transfer files between the SuperSE and my modern MacBook Pro. I’d also like to be able to create a backup of existing files on the internal hard drive (the previous owner wants their files back), format the internal hard drive, and create a fresh System 7.1 installation. The FloppyEmu does work with the SuperSE, but only in floppy mode. Computers with accelerator cards will not work with the FloppyEmu’s HD-20 emulation mode.

However, a device called the SCSI-2-SD by Inertial Computing will. This device works on the SCSI bus instead of the floppy port, allowing for faster speeds. The SCSI-2-SD will also work as a replacement for an internal drive, but I’d really like to keep the original Maxtor drive going for maximum nostalgic value.

My end goal with the SuperSE is load System 7.1 onto it and use it as a vintage desktop publishing and multimedia computer. I’d like to try to get QuickTime and Arnold’s MIDI Player running on it, among other things.

Stay tuned for updates! Be sure to follow me on Twitter (@gfuller_blog) to receive additional updates as the occur.

This post written on a 1988 Macintosh SE using Microsoft Word 4.0.