Macintosh Classic II upgrades

Open hardware SCSI emulator with SD-backed storage, optional Wi-Fi networking, and host-side management tools.

For this system (exact model): The official compatibility list names the Macintosh Classic II.

Current seller checks on 2026-07-27 found a $39 internal 50-pin Pico 2 W kit, a $49 assembled external DB-25 model, a $49 PowerBook model, and a $59 assembled Ultra Narrow 50-pin model at authorized seller ToTs RETRO. JCM also carried assembled Ultra hardware and model-specific Macintosh adapters. Prices, stock, included media, and support differ by seller. Ultra models require Berg or Molex power and cannot run from SCSI termination power. The initial Ultra hardware release is not yet open hardware, although its firmware remains GPL; the project says hardware licensing will open later.

Turns a spare compact-Mac logic board into a small desktop computer with modern power, display, and storage hardware.

For this system (exact model): JCM sells a model-specific printed enclosure for Macintosh Classic II logic boards. Confirm the required Classic-family power and video boards rather than assuming the SE-family J12 pinout.

On 2026-07-24 JCM showed 5 printed 128K/512K cases, 3 Plus cases, 2 SE/SE30 cases, and 5 Classic/Classic II cases in stock. This is an enclosure, not a complete computer: supply a working logic board, power and video electronics, storage, input devices, display, cabling, and other desired parts. GutBomb's printable design is CC BY-NC-SA and does not cover the separate electronics.

Uses an SD card to emulate Apple floppy drives and, on supported systems, HD20 or SmartPort hard disks.

For this system (stated family): The manual covers classic Macintosh systems in this generation. Install the Macintosh/Lisa firmware, connect through DB-19 or the documented internal header, and choose a floppy or HD20 image mode supported by the host.

The BMOW store showed the assembled Model C sold out at $109 on 2026-07-27. The separate Deluxe bundle is the same emulator packaged with accessories rather than a different product family. Check the direct product page for a restock.

Breaks out compact Macintosh power rails and video signals for custom logic-board projects.

For this system (exact model): Use the Classic/Classic II version to expose the logic board's main power buses and video signals. A separate supply and external video solution are required; do not substitute the SE/SE30 pinout.

JCM showed 17 SE/SE30 units and 6 Classic/Classic II units in stock on 2026-07-24. These are custom conversion and test-bench parts, not drop-in upgrades for intact computers. The two Macintosh groups use different J12 signal mappings, so use only the version intended for the installed logic board. JCM recommends 16 or 18 gauge leads with a modern ATX supply on the SE-family board.

Adds an optional Motorola 68882 floating-point coprocessor to the Macintosh Classic II.

For this system (exact model): Both variants are designed for the Classic II and its Performa 200 alias. The Infinity board's overclocking path requires desoldering J3, adding a J2 selector, and installing a correctly oriented 5 V oscillator. The Jurassic board uses a SYS or OSC jumper and also requires a separately supplied 5 V oscillator for asynchronous operation.

Human review found the Infinity Products page orderable on 2026-07-24. Jurassic Computing showed a $35 Tindie purchase path with selectable FPU options on 2026-07-27; a 5 V oscillator is not included, and economy mail from France to the United States was suspended. Check the exact seller option for a fitted 68882.

New replacement for the analog-board to logic-board signal cable in four compact Macintosh models.

For this system (exact model): Replacement analog-to-logic-board cable for a Macintosh Classic II. Use only with the matching Classic-family board set; do not connect it to SE-family parts.

The JCM page showed 17 units in stock on 2026-07-24. Never use the cable to combine an SE or SE/30 board with a Classic or Classic II board: the identical-looking connectors carry signals on different pins, and mixing the two groups will damage the computers.

Upgrades compact Macintosh computers with a 16 MHz 68030 and optional 68882 FPU through original vintage cards or modern recreations.

For this system (exact model): MicroMac's original product page names the Performa 200, an alias of the Macintosh Classic II, as an available vintage variant. The modern clone project does not establish Classic II support; verify the exact original card, clip, software, and host before buying used.

The open clone remains buildable, but MacEffects' assembled Macintosh SE variant was sold out on 2026-07-27. The original MicroMac page was last modified in 1998, so its order form and prices are archival rather than a current purchase path. Modern-clone operation has been tested in the Macintosh Plus and SE, but not in the Classic; no secure socket has been found for the Classic's PLCC CPU. Host-specific U7 and SJ2 settings are mandatory. GAL16V8-15 and PALCE16V8-15 parts are tested, while ATF16V8 and other speeds are not.

Mounts a BlueSCSI or another 50-pin SCSI device directly above a Macintosh internal SCSI connector.

For this system (exact model): The open project explicitly lists and shows use with the Classic II. IIcx and IIci operation is described there only as possible and unverified, so those targets are not attached.

The current store page listed partly assembled and complete options without an out-of-stock marker on 2026-07-24. The maker repository also provides assembly material and Gerbers.

DIY 4 MB 30-pin Macintosh memory module made by transplanting DRAM from a compatible 16 MB 72-pin SIMM.

For this system (exact model): The maker says two completed 4 MB modules bring a Classic II to its maximum memory configuration.

The current store listed the bare kit and optional passive-component set without an out-of-stock marker on 2026-07-24. Compatible donor DRAM is not included.