Tag: diy

Translates a PS/2 mouse into Commodore 1351-style analog mouse signals for the C64 and C128.

Retro Computer Store listed an assembled adapter as available for USD 16 on 2026-07-30. PCBWay exposes a through-hole fabrication route with Gerbers, a bill of materials, and programming notes. The current assembled version supports PS/2 mice and PS/2-compatible serial mice but explicitly does not support a USB mouse through a passive PS/2 adapter. A working SID analog-input path is required; some replacement SID implementations omit it.

Selects which 1088XEL joystick port receives input from its PS/2 mouse.

The maker publishes a schematic and Gerbers and links to both bare-PCB layouts at OSH Park. This is a self-built selector rather than a current assembled product; the generic layout requires suitable LED and switch openings in the chosen case.

Replaces the Atari 1200XL memory subsystem with 1088 KB of SRAM.

The maker publishes a schematic, Gerbers, and the programmed-logic JED file but no bill of materials. The installation removes twelve socketed chips from the motherboard and transfers four original chips to the upgrade. The RF choke may need to be bent or removed for clearance. Install the 1 mm board only with the motherboard out of its case and supported on a solid surface because the stacked machine-pin sockets require substantial insertion force.

Rebuilds an Atari 800XL around a newly manufactured Revision 1.2 motherboard with bare, programmed-chip, and assembled options.

The main board page reported two units in stock on 2026-07-27. A completed board requires the buyer to send a functional, non-returnable donor board because original Atari chips and some connectors are no longer made; the seller estimates about two weeks for completion and testing after receiving it. The separately orderable programmed-chip page reported four sets in stock. Its EMMU must match the intended memory configuration and is optional for a 64 KB-only build.

Open hardware and software platform for building Raspberry Pi Pico-based Apple II peripheral cards.

JCM showed 36 assembled A2Pico cards in stock with selectable preinstalled firmware on 2026-07-24. Choose the board and firmware together. The simpler A2Pico2Lite design uses a Pico 2 and omits the original A2Pico microSD slot. Unpowered USB OTG hubs can cause device problems, especially with mice.

Repurposes supported Raspberry Pi Pico Apple II video cards as a USB HID mouse interface.

A complete setup needs a supported A2VGA Revision 1.6 or modified older A2VGA or A2analog card, a Micro-USB-to-USB-A adapter, and a driverless USB HID mouse. USB hubs are not supported. Installing A2USB removes the card's VGA function until different firmware is loaded. Remove the Pico or card from the Apple II before using BOOTSEL to update firmware, and choose the PAL or NTSC build with the appropriate 50 or 60 Hz interrupt default.

Loads cartridge images and XEX files from USB-managed flash storage through an inexpensive RP2040-based Atari XL/XE cartridge.

A8Renegade's live Shopify product data and collection reported the assembled cartridge orderable on 2026-07-27, despite a contradictory sold-out label in the rendered product page. The complete open design also remains buildable.

Uses an STM32 and SD media as a mature open Atari ST hard-drive emulator with ACSI, disk-image, and GemDrive modes.

The upstream project describes hardware and software version 5.00 as finished and mature. Its release package contains files for ordering a compact board with assembly, but the builder must flash it initially with a 3.3 V-compatible USB-to-UART adapter and supply 5 V USB-C power, media, and an optional CR2032. Firmware 1.x, 2.x, and 3.0-or-later boards have different compatibility paths; the current compact design should use the matching current firmware. Lotharek's separate four-slot ACSI2STM Redux case design remained not yet available on 2026-07-27 and is not represented as a current assembled seller.

Recreates the circa-1990 AdLib OPL2 FM-synthesis sound card as a buildable open hardware project.

This is a self-assembly reproduction rather than a currently sold assembled card. The repository has no packaged release; use the project files and parts list directly.

Modifies an Amiga 1000 to boot Kickstart from four EPROMs while retaining access to its 256 KB daughterboard RAM.

This is an advanced board-level modification, not a plug-in board. It requires a GAL16V8A, four 27C512 EPROMs, a legally obtained Kickstart image, device programming, desoldering, jumper installation, and PCB trace cuts.

Recreates the Comspec SA-1000 sidecar to add a SCSI bus and real-time clock to an Amiga 1000.

This is a self-assembly project with a schematic, bill of materials, and fabrication package. It requires programmed GALs and ROMs plus careful alignment of the 86-pin edge connector. The alternate RTC-72421 clock chip is suggested but untested.

Published twelve-chip Motorola 6800 teaching coprocessor that takes control of the Apple II bus.

This is a published construction project, not a current kit or finished product. The paper supplies a circuit diagram and tested monitor listing but no PCB layout, Gerbers, bill of materials, or explicit reuse license. A builder must recreate the board, source period logic, program a 2716 EPROM, and validate timing and bus loading.

Provides a bare recreation of the original Apple II Revision 0 motherboard for restoration or a ground-up build.

The bare board was in stock and backorderable on 2026-07-24. It does not include the required components, ROMs, DRAM, assembly labor, or bring-up work.

Connects a Raspberry Pi Zero 2 W to an enhanced Apple IIe for virtual disks, networking, Linux commands, and file transfer.

The upstream project describes Revision 7 as a prototype rather than a finished product. Most development and testing used an enhanced Apple IIe with the card in slot 7; the firmware assumes the slot 3 80-column card and lowercase support. A Pi Zero 2 W can consume roughly 170 to 250 mA from the Apple II's 500 mA total slot budget. Revision 6 and later can use external USB power after the documented jumper change, but the firmware will hang if the Pi is not powered.

Generates crisp 640 by 480 VGA from Apple II video memory using a Raspberry Pi Pico bus-snooping card.

JCM showed 36 assembled A2 VidGA cards in stock on 2026-07-24, with firmware choices for Apple II and II Plus or Apple IIe. RetroFletch's A2 Analog seller was taking a break on 2026-07-27; its published board has a critical VGA IDC footprint error, so the cable's red wire must face the motherboard. A2 Analog can also conflict with some accelerators, card autodetection, CFFA3000, and ROMX configurations. Infinity Products' SMC A][ VGA Mini was out of stock, and Laser's assembled Mark Aikens variant showed zero stock. Choose the exact hardware and firmware branch rather than treating every variant as interchangeable.

Provides ProFile-style block storage from a raw SD card for enhanced Apple IIe and Apple IIgs systems.

The repository publishes binaries, firmware, VHDL, schematics, layout files, Gerbers, and a bill of materials, but no explicit license was verified. Capacity is limited to four 65,535-block volumes, or about 128 MB total. Under ProDOS, programs on the third and fourth partitions have a documented launch problem. This is a build project rather than a current assembled product.

Lets a 1088XLD emulate a joystick with its PS/2 keyboard arrow and trigger keys.

The project publishes schematics, Gerbers for both required boards, a bill of materials, and TK-II 2.7J firmware. A complete installation needs the piggyback board, interface board, ribbon cable, and programmed keyboard-controller firmware. The three auxiliary outputs are momentary open-collector signals and may need latches for some uses.

Adapts the Pixels Past 8K or 16K EPROM cartridge into an eight-selection homebrew multicart for the Atari 800XL.

Human review found the combined visual material sufficient for a skilled builder. It remains an adaptation rather than a revised fabrication package: the linked Gerbers and assembly material are for the unmodified Pixels Past single-cartridge PCB, while the eight-way changes appear only in an inline diagram with no separate revised Gerbers, bill of materials, ROM-preparation guide, or textual selection instructions. Pixels Past licenses its base files under CC BY 4.0, but no license for the eight-way modification was verified.

Adds a battery-backed real-time clock to Atari XL and XE computers as an internal module, pass-through cartridge, or circuit inside another cartridge.

The project page publishes a parts list, clock and address-decoder schematics, battery and rechargeable-cell backup circuits, and an ARC handler archive. It recommends internal installation because the pass-through and inside-another-cartridge forms may cause more problems. The page does not provide a step-by-step bus-wiring guide: an internal build must source D0-D3, A0-A7, R/W, phase 2, power, and D5xx cartridge-control signals, while a cartridge build uses the cartridge connector. No explicit project license or current assembled seller was verified.

Recreates the Gravis Ultrasound PnP ISA sound card around an AMD InterWave chip, with an optional IDE CD-ROM interface.

The maker has not fabricated or tested this board and has not generated a fabrication package. It also requires an AMD AM78C201 InterWave chip. Treat it as an experimental design and build at your own risk.

Packages a Raspberry Pi 3B+ and RP2040 keyboard interface into an original C64 or C64C case as a low-latency BMC64 system.

Current shortboard and longboard v4.0 files and an easier-to-assemble v4.0.1A variant were available on 2026-07-27. No assembled seller was verified. A complete build needs both PCBs, components, assembly, a Raspberry Pi 3B+, Waveshare RP2040-Zero, microSD card, original C64 or Mechboard64 keyboard, suitable case, and power. BMC64 itself is not compatible with Raspberry Pi 4B or 5.

Adds 1 MB of banked RAM to an Atari 1200XL or 800XL with a 30-pin SIMM and custom refresh and bank-selection logic.

The archived article provides the circuit discussion, 1200XL connection table, SIMM pinout, and software notes but describes the 800XL only as having similar connection points. It is an advanced historical wire-and-perfboard build. The author reports that the SpartaDOS cartridge does not function with this configuration and that ordinary SpartaDOS and much commercial software see only a 320XE-style subset; MYDOS 4.5.1M or newer needs the documented page sequence.

Uses a PS/2 keyboard on supported Commodore computers or converts their original keyboards and optional joysticks for a PS/2-equipped host.

The RETRO Innovations store exposed a configuration selector and Add to Cart path on 2026-07-30, with the bare PCB listed at USD 6 and configured kits priced separately. Kits and assembled units are made after ordering and normally take four to five weeks. The maker explicitly treats C=Key as a project rather than a fully supported product because its firmware is not extensively tested or easily upgraded; an AVR programmer is strongly recommended. Use a true PS/2 keyboard because passive USB adapters may not work.

A passive buildable adapter that converts C128 80-column RGBI to 15 kHz analog RGB and adds monochrome composite output.

The repository publishes KiCad schematic and board files plus Gerbers. This is not a scan doubler or scaler, so the connected display must accept 15 kHz analog RGB with separate 5 V horizontal and vertical sync. The design has no CGA brown fix, does not provide VGA identification or communication signals, and will not work with a downstream converter that requires composite sync. The maker reports a successful Dell 27-inch monitor test but calls the test computer a 'C128cr'; do not infer separate C128D or C128DCR testing from that ambiguous label.

Adds a buffered external C128D keyboard connection to a Commodore 64 while retaining the original keyboard.

The surviving workshop page provides a schematic, pin map, parts list, and verified build instructions, but no PCB files, kit, or explicit reuse license. It warns that a direct long-cable connection can overload and destroy the C64 CIA. The buffered design was intended for cables as long as 10 meters, although its troubleshooting section still recommends shortening a troublesome cable to about one meter.

Generates configurable YPbPr or RGB from VIC-II bus activity with an FPGA while retaining improved composite and S-Video output.

VideoGamePerfection's EUR 60.00 kit was out of stock on 2026-07-27, but the complete open design remains buildable and upstream firmware 2.12 was released on 2026-07-03. This is a substantial soldering installation, and the original RF output is removed.

Adds an inexpensive battery-backed real-time clock to a Commodore 64 through the user or cassette port.

The current project page provides version 1.0 software and exact wiring for three C64 connection choices. Gregory Nacu's i2c6502 source independently documents the C64 user-port PB2/PB3 implementation and DS3231 example under the MIT license. A generic RTC module, connector or pass-through board, wire, and battery are separate. Many inexpensive modules include a charging circuit intended for a rechargeable cell; follow the project's component-removal instructions before substituting a CR2032 or CR1225 primary cell. The Timo Voutilainen package does not state a hardware fabrication or software license.

Provides an open build for selecting either Commodore 64 control port from one Atari-style joystick, with optional second-fire and autofire circuits.

The repository supplies KiCad files, Gerbers, a schematic, bill of materials, and assembly guidance. Inspect the completed board for solder bridges and support it while pressing its buttons. Never move jumpers while powered or map two physical inputs to the same function. Do not connect a Sega Genesis or Mega Drive controller; the maker warns that it may damage the C64 and directs those controllers to the separate Mega Switcher.

Turns as many as two Atari-style digital joysticks or four paddles into USB input devices for a modern computer.

The repository supplies board fabrication files, a schematic, Arduino firmware, a bill of materials, and assembly guidance. A build needs an Arduino Pro Micro and the components selected for either the Atari-style or Sega configuration. Paddle mode is a JoyConverter firmware option selected while powering the adapter.

Adds a Yamaha V9958 or V9938 video processor, 128 KB of dedicated VRAM, RGB output, sprites, and enhanced graphics modes through the expansion port.

The project publishes the final 1.0 PCB, schematic, Gerbers, GAL files, documentation, and demonstration software, but no current assembled seller was verified. A build requires a V9958 or modified V9938 configuration, two compatible DRAM devices for 128 KB of interleaved VRAM, programmable logic, an EPROM or EEPROM if desired, and substantial surface-mount assembly.

Buildable NodeMCU Wi-Fi modem for the Commodore 64 user port with voltage level shifting and status indicators.

The complete project remains downloadable. Retro-Updates listed an assembled revision-2 version for the C64 and C128, but it was out of stock on 2026-07-30. Revision 1 fits only the smaller WeMos NodeMCU v3 form factor; revision 2 supports both common board widths.

Adds two joystick ports to a compatible Commodore user port for four-player games that support the CGA adapter protocol.

Protovision showed 17 individual Computers adapters in stock at EUR 25 with a one- to two-week shipping estimate on 2026-07-30. CBMretro also exposed an add-to-cart route for Pasi Lassila's enhanced Neat design at EUR 26.90, and ZGCS showed two assembled compatible boards at USD 22 on Tindie. Install or remove the adapter only with power off and observe connector orientation. Do not connect it to a Plus/4: individual Computers warns that doing so risks damage. The PET 2001 user ports lack the required power connection, and the maker discourages modifying a historic machine to add it.

A simple buildable RGBI-to-analog-RGB adapter for 15 kHz-capable displays with a VGA connector.

The PCBWay project supplies a shared board-order path and a short component list. Assembly is required. This is explicitly not a scan doubler, so most ordinary VGA displays will not work; verify that the exact monitor accepts 15 kHz analog RGB. The maker reports a successful test with a flat Commodore 128 and an Acer G206HQL, but does not separately document C128D or C128DCR testing.

Open replacement battery module for the Compaq Portable III using a CR2477N coin cell.

This is a self-assembly project rather than a retail product. Follow the documented cell polarity and solder the pin headers in the specified upside-down orientation.

DIY diagnostic ROM and loopback harness for PAL and NTSC Commodore 264-family computers.

Rob Clarke's current download directory offered Diag264 0.97 on 2026-07-30. The maker also offers a programmed EPROM at media and postage cost by email. The software is CC BY-NC-ND 4.0: unmodified personal distribution with attribution is allowed, but modification and commercial resale are prohibited. The maker warns that some third-party marketplace copies were unauthorized or modified. Loopback hardware may be resold when the attribution conditions are met.

Expands a 16 KB Atari 600XL to 64 KB with two 41464 DRAMs and three wiring changes.

The archived instructions call for two 41464-10 or compatible DRAMs, hookup wire, soldering tools, and optional sockets. Chips may need desoldering, several pins and resistor leads must be isolated, and fine motherboard traces are exposed; the author explicitly says to attempt it only if the diagram is understood and at the builder's risk. This is a historical modification guide, not a current kit.

Open 1 MB C64 flash-cartridge family that can be reprogrammed directly by the computer without an EPROM programmer.

The EasyFlash and EasyFlash 1CR designs remain buildable. Poly.play's assembled original-style EasyFlash was out of stock on 2026-07-30.

Current and DIY versions of the C64 and C128 utility cartridge with fast loading, freezer, monitor, BASIC extensions, and desktop software.

Daniel Mantione currently offers the assembled Final Cartridge III 101% with a case through his project page and SellMyRetro. It arrives without firmware, so the buyer must flash a compatible image before use; version 2 of the 101% firmware and the C64 flasher are available from the maker. The separate C64iSTANBUL III+ project offers an orderable through-hole PCB, bill of materials, and 64 KB or 256 KB EPROM images, but it requires assembly and an EPROM programmer. PCBWay labels that shared hardware project CC BY-SA 3.0. The original and derivative firmware remains copyrighted and is not presented as freely licensed.

Adds a two-drive floppy controller and DS1302 real-time clock to RC2014 and RCBus systems.

Tindie listed the complete Flock V2 kit without an out-of-stock notice on 2026-07-25, and open build files remain available. The CR2032 battery and optional 300 Kbit/s parts are not included. The drive-power output is unfused; avoid overloading or shorting it.

A DIY USB floppy interface and cross-platform toolkit for reading and writing unusual disk formats with a conventional PC floppy drive.

Building the original interface requires a compatible PSoC 5 development board, a floppy connector, soldering, a conventional PC floppy drive, cabling, and drive power. The project warns that not every listed format has been tested on physical disks; its dinosaur markers identify encoders or decoders based only on captured data. Copy-protection schemes are not a core focus.

Connects one six-button Sega Mega Drive or Genesis controller to both C64 or C128 control ports with port switching and extra button mappings.

BackBit says it no longer has capacity to build this former product and has released the design under GPL-3.0. The repository supplies KiCad board and schematic files, CUPL source, printable case files, and a bill of materials; a build also needs the listed ATF1502 CPLD and an ATDH1150USB programmer. The former store URL returned 404 twice, including after the required 60-second retry.

Open ISA controller that connects ATA or IDE drives to an XT-class computer.

Retro Electronics listed the bare Revision 4 PCB in stock on 2026-07-25. The builder must source the components, assemble the card, and follow the project instructions; no current kit or assembled-board availability was verified.

Provides selectable Apple Slinky or RAMFactor-compatible memory using modern low-power SDRAM.

The assembled Tindie card was out of stock on 2026-07-24 and had been sold out since January 23, 2025. Schematics, board files, CPLD firmware, utility software, and fabrication files remain available under the project's dual-license terms.

Provides MDA and CGA-compatible display modes with 31 kHz VGA output for modern monitors and capture devices.

This is a self-assembly project. The maker advises checking for shorts between each power rail and ground before installation; the oscillator configuration also affects CGA composite color accuracy.

Open four-layer 30-pin FPM memory family with 4 MB, parity, 16 MB, and early-Macintosh PAL SIMM variants.

The assembled GW4192A kit was out of stock on 2026-07-24 and had been sold out since October 26, 2022. GW4194A had been sold out since January 19, 2023. Open schematics and layouts remain available. These modules support FPM, not EDO, even when an EDO chip is wired to operate in FPM mode. Check refresh type, parity, capacity, bank population, and physical clearance against the exact computer before building or installing a variant.

Open low-power 2 MB geoRAM-compatible expansion cartridge for the Commodore 64.

The assembled Tindie cartridge was out of stock on 2026-07-24 and had been sold out since June 10, 2024. The open design remains buildable. This is geoRAM memory, not an REU: software must explicitly support geoRAM. Most C64 programs use neither expansion-memory type, and GEOS needs an added geoRAM driver on its boot disk.

Open 64-pin ROM SIMM with selectable 32-bit-clean System 6 and System 7.1 ROM disks for six 68030 Macintosh models.

The assembled Tindie module was out of stock on 2026-07-24 and had been sold out since May 7, 2025. Hardware, software, and fabrication files remain public. Most tested 68030 accelerators work, but some 68040 accelerators do not; select the stock IIsi or IIx ROM when the custom image is incompatible. Only 8 MB of the 16 MB flash can be selected at once, with the computer powered off before changing the switch.

Open 512 KB 68-pin Macintosh VRAM SIMM built with new 80 ns or faster memory.

The assembled Tindie module was out of stock on 2026-07-24 and had been sold out since May 5, 2024. Schematics and board files remain available for commercial and noncommercial use. A 512 KB module can replace a 256 KB module where the connector is compatible, but that machine will use only 256 KB; never mix capacities within one VRAM bank.

Open low-profile card that adds 3 MB to a Macintosh Classic using two modern DRAM chips.

The assembled Tindie card remained out of stock on 2026-07-27 and had been sold out since August 13, 2025. The schematics and board layouts remain available for commercial and noncommercial use.

Open hardware reproductions of the two interface cards used to connect an IBM PC or XT to a 5161 Expansion Unit.

Rebuilds a Commodore 64 around a modern replacement motherboard with improved power, protection, video, diagnostics, and ROM switching.

CBMSTUFF marks the motherboard discontinued. Its product page, build manual, BOM, and supporting software remain online, and some optional parts remain listed. Used boards may occasionally appear on secondary markets.

Open RTL8019 Ethernet card that brings NE2000-compatible networking to 8-bit ISA computers.

The fully assembled card was out of stock on Tindie on 2026-07-25 and had been sold out since December 15, 2025. Open KiCad files, Gerbers, software, and a separate bare-PCB path remain available. A DIY build needs a unique valid MAC address and surface-mount RTL8019 assembly.

Implements an experimental STM32-based USB host for operating ISA cards on an external backplane.

Treat this as an unfinished development platform, not a turnkey USB-to-ISA product. The repositories provide Revision A fabrication files and early STM32 firmware but no documented host application, VM integration, release, or end-user procedure. A linked 2020 development thread demonstrates predecessor Arduino Mega experiments with serial ISA reads and writes, isapnptools, an Aztech sound card, and PCem, but does not establish that those workflows were implemented for ISASTM. Revision A has signal-integrity and reset-pull-up errata, and USB High-Speed is untested and may not work. The required ISA backplane supplies power.

DIY replica of the 1985 C64 freezer cartridge that captures RAM, I/O, and CPU state to disk.

The replica repository's 2021 v1.0a files include ISEPIC-named Gerbers, an Altium PCB project, schematic, bill of materials, and disk images. Its README mistakenly links its PCBWay order button to a different 8 MHz Z80 card; do not order that board as an ISEPIC. Review and fabricate from the included ISEPIC files instead. Replica hardware files outside the Docs and Software directories are CC BY-NC-SA 4.0. The original 1985 ISEPIC software remains copyrighted and is not covered by that hardware license.

Vintage and DIY C64 freezer cartridge that saves restartable memory snapshots to disk, tape, or EPROM-oriented cartridge files.

DDI's Re-Capture page still exposes Gerbers, a parts list, a Capture ROM archive, and a manual link. The parts list specifies the EPROM, SRAM, logic, passives, and switch choices, but ReplayResources says the schematic is still missing and no complete assembly or test guide was found. Neither page supplies a clear license for the reproduction files or Capture software. ReplayResources quotes permission relating to Jason-Ranheim's separate Promenade materials but explicitly says its own Capture permission requests went unanswered, so the catalog does not treat the Capture ROM as open or freely licensed. Original cartridges remain worth searching for used.

Programs supported PIC microcontrollers from an Atari 8-bit computer through a joystick port.

Schematics, Gerbers, parts information, Atari software, and bare-PCB order links are public. A build still requires assembly and careful device orientation. Confirm that the exact PIC is supported before programming it; the STIK socket does not support every PIC package or family.

Intercepts the C64 keyboard matrix to add programmable shortcuts, macros, remapping, remote control, and sixteen hardware-control lines.

The maker currently offers revision 4 assembly kits with a PCB, preprogrammed ATmega, and components except connection cables for EUR 30 by email. Kits are made in small spare-time batches and may require prepaid backordering. Version 1.6 firmware, configuration tools, Gerbers, KiCad design files, schematics, and source remain downloadable.

Adds a hardware azimuth indicator to a Commodore 1530 Datasette so its tape head can be aligned without running a program.

The GPLv3 reverse-engineering files remain available. Shareware Plus described a small reproduction batch at GBP 16, with an optional GBP 6 brass adjustment rod and GBP 5 printed support, but that page was last updated on 2025-01-01 and uses email ordering. Confirm present stock and exactly which parts are included. Installation modifies a Datasette and requires soldering to points that can differ between PCB revisions.

Open replacement RAM expansion board for an original or Reloaded Macintosh Classic logic board.

The public repository supplies Gerbers, BOM, and pick-and-place data under a noncommercial Creative Commons license. The Classic BBU limits total memory to 4 MB; larger SIMMs do not raise that limit. Builders must source 256x4 SOJ RAM, SIMM sockets, and the listed parts.

Recreates the Macintosh IIfx logic board with new board files, schematics, a parts list, and rewritten PAL logic.

This is an advanced noncommercial board-build project, not an assembled product. The recreated PALs need suitable 16V8 or 20V8 devices. Low-power ATF16V8B parts do not work, and ATF16V8C parts may be problematic.

Recreates the Macintosh LC 475 and Performa 475 logic board as a buildable replacement PCB.

This is an advanced noncommercial board-build project with no assembled purchase path. The repository warns that fabrication data was generated for JLCPCB and may need changes for other manufacturers.

Recreates the Macintosh Quadra 950 logic board with new fabrication and assembly data.

This is an advanced noncommercial board-build project with no assembled purchase path. Its Gerbers and placement data target JLCPCB and may need changes for another fabricator.

Provides a newly manufactured bare replacement PCB for rebuilding a damaged Macintosh SE logic board.

The authorized bare PCB was sold out on 2026-07-27. It includes no populated components and is an advanced board-level rebuild. The best public follow-up found was a maker-authored TinkerDifferent discussion, but no complete official BOM, placement package, donor-chip list, supported original-board revisions, or tested bring-up procedure was established.

Redesigns the SE/30 logic board as a buildable replacement with Gerbers, placement data, a BOM, and recreated programmable logic.

This is a fabrication package, not an assembled order path. The published Gerbers were generated for JLCPCB and may need adjustment for another fabricator. Low-power ATF16V8B programmable-logic parts do not work, and ATF16V8C parts may also cause problems. The build still depends on Apple custom ICs sourced from donor hardware.

Adapts selected simple C64 or C128 I/O cartridges to the VIC-20 expansion port.

RETRO Innovations retains a USD 11 product page and publishes the schematic and PCB artwork under CC BY-SA 4.0, but the extracted store page did not expose an unambiguous stock or Add to Cart state on 2026-07-30. Confirm assembled availability before ordering or build from the project files. The repository README's first paragraph mistakenly says the target is a C64, SX-64, or C128; its title, About text, usage section, official product page, and store page all establish that the adapter is for a VIC-20.

Emulates Commodore IEC devices and loads files from local flash, an SD card, or network servers over Wi-Fi.

The project provides source, several ESP32 hardware profiles, build instructions, and a browser-based firmware flasher. No direct retail source was verified, so builders must select matching hardware and firmware before connecting it to a computer.

Replaces a Commodore 64 keyboard with a modern Gateron-switch mechanical assembly in breadbin or C64C cases.

AmericanRetro.shop offered assembled and kit versions, and its Tindie assembled listing showed two revision 1.07 units at USD 194.99 on 2026-07-30. MtnBuffalo also publishes revision 1.07 fabrication, bracket, firmware, bill-of-materials, and assembly files. The physical product and MechBoard64 brand require separate permission for commercial manufacture even though the published design files permit personal building and modification.

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

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.

Combines an approximately 16 MHz 68030 and optional 68882 on a compact MicroMac Performer remix made for a Macintosh Plus clone.

Human review confirmed that the JCM Edition was in stock on 2026-07-24 and that JCM offers the CPU and FPU as a separate linked item. The open project and bare-PCB path remain available. Confirm the Edition's exact assembly state and mounting-clip contents before ordering. Installation requires access to the 68000, PLD choice is important, and some software may have distorted audio.

Open dual-SID board with mixed 6581 and 8580 support, runtime address selection, channel mixing, paddle compatibility, and stereo output.

The complete GPL-2.0 hardware, GAL, Gerber, and build documentation remains available. A Tindie assembled listing reported out of stock since 2020 but says the seller may assemble a unit on demand; treat that as a contact route rather than stocked availability. SID chips are excluded.

Open ISA controller with two floppy controllers for up to eight drives, plus optional serial and BIOS hardware.

The assembled and tested card was out of stock on Tindie on 2026-07-25 and had been sold out since January 31, 2026. Open KiCad files, Gerbers, a bill of materials, and a manual remain available. Optional 5 V-on-pin-3 jumpers are only for compatible PS/2-style floppy drives and can damage standard drives if installed incorrectly.

Converts a PS/2 mouse into Atari 8-bit or Atari ST quadrature mouse signals.

The maker publishes beta firmware, source, a pinout, and programming files but not a finished adapter PCB on this page. A build requires a programmed PIC16F1847 and suitable wiring or an enclosure. For an internal installation, connect behind the computer's in-line joystick resistors so a plugged-in joystick cannot directly short the PIC outputs. USB mice work only when they also implement the PS/2 protocol.

Adds IDE hard-disk storage through cartridge, internal flash-OS, and original Atari 800 DIY implementations that predate MyIDE-II.

The official Atarimax page said the interfaces were in stock and extended its sale through 2026-07-31 when checked on 2026-07-27; verify that short-lived offer before ordering. The family has been superseded by MyIDE-II but remains functionally distinct because it accepts IDE devices rather than providing MyIDE-II's onboard CompactFlash and FAT32 loader. The cartridge requires a 64 KB XL or XE. Internal installation ranges from an OS-ROM socket plus three signal wires in an 800XL to extensive socket, jumper, MMU, BASIC, and wiring changes in a 1200XL. Mr. Atari's original 800 version is an advanced personal-use DIY design with schematic and firmware files but no complete build instructions or bill of materials.

Sharpens video on some PAL or NTSC Atari 600XL and 800XL boards by disconnecting one filter capacitor.

The recovered 2017 discussion says to lift or cut one capacitor leg, making later restoration possible, and the author tested PAL and NTSC machines only. SECAM compatibility is unresolved. Several commenters report that later Revision D 800XL boards omit C56 or use a different layout, so identify the exact board revision and component before changing anything. The quoted 80 percent improvement is the author's subjective estimate, not a measured specification; more complete video upgrades may produce better output.

Replaces the circuit board in an original or reproduction NES controller so it works as a Commodore 64 gamepad.

AutumnHippo exposed an add-to-cart route with a USD 8 base price on 2026-07-30. The page offers a bare PCB, a kit with a reproduction case, and a fully assembled controller, but it does not expose every option price in extracted text. A bare-board build needs a case, a correctly traced cable, a switch or solder bridge, and basic soldering. The maker also states generic Amiga and Atari computer compatibility, but exact model relationships are not attached without model-specific evidence.

Converts two Wii Nunchuk or NES and SNES Classic Mini controllers into the two Commodore 64 control-port inputs.

Sordan exposed a current Buy route at EUR 30.99 excluding VAT on 2026-07-30. The maker also publishes KiCad files, Gerbers, firmware, assembly instructions, printable cases, and a GPL-3.0 license, and invites direct contact for DIY kits. Controllers and wireless receivers are separate. The guide's acrylic-case tile is an enclosure accessory and is folded into this hardware family.

Open PCB that exposes every Commodore 1530 Datassette connector line for Tapuino builds and cassette-port adapters.

The repository provides the KiCad board, schematic, footprint, and documentation files and invites builders to fabricate the open hardware. PCBWay currently offers the 26.92 by 26.03 mm V2 design as a 1.6 mm, two-layer bare PCB and labels that shared project CC BY-SA 3.0. No connector, Mini-DIN lead, enclosure, Tapuino electronics, buffering, isolation, fusing, or current limiting is included or documented. Review the manufacturing files and wiring before ordering and connect hardware only with power off.

Emulates writable Atari XL and XE floppy drives from SD storage using the original ATmega8 SDrive design or the NUXX packaging variant.

The original GPL-3.0 hardware, firmware, Atari-side software, documentation, and source remain public. Its 2009 documentation specifies cards up to 2 GB with FAT16, while the repository also contains a later 2012 SDHC-supporting source revision; match the firmware, media setup, and documentation deliberately. The NUXX archive is frozen as of 2020 and says its function is identical to original SDrive, but adds a different PCB, enclosure, connector options, and optional STK200-style parallel-port programmer. No current assembled seller was verified.

Uses a 1 MB 30-pin SIMM and GAL controller to add switchable Compy Shop or Newell/RAMBO banked memory to Atari XL and XE computers.

The Polish project page publishes a schematic, GAL JEDEC file, utilities, parts list, full 800XL and Freddie-equipped 800XLF instructions, startup tests, and timing troubleshooting. Installation is highly invasive and may require trace cuts, lifted or bent IC pins, motherboard timing changes, and RAS-delay tuning for a particular machine. The page groups the 600XL and 1200XL with older 800XL memory-control hardware but does not provide separate step-by-step guides for those models. No explicit project license was verified.

Provides source files for a Cherry-compatible Commodore PET N-type keyboard with printable supports and keycaps.

The repository was actively updated in June 2026 and supplies PCB, firmware, support, test, and keycap files. It is an advanced source build rather than a complete retail kit. The maker built it principally for the Micro-PET and Ulti-PET family and explicitly says installation in an original PET is possible in principle but untested.

Provides a Cherry MX replacement-keyboard PCB for a graphics-keyboard Commodore PET or Tynemouth Mini PET.

TexElec listed the bare PCB set in stock for USD 27.99 on 2026-07-30. Switches, keycaps, electronic parts, cable, support structure, insulation, and the custom mounting work required by an original PET are not included. The optional Shift Lock circuit needs a safe 5 V connection inside the PET.

Open, reversible Pico ATX power-adapter family for the Macintosh 128K, 512K, Plus, SE, and SE/30.

On 2026-07-27, the 128K/512K/Plus listing showed order controls at $29.99 and the SE/SE30 listing showed order controls at $34.99. Both offered kit and assembled choices. Their United States shipping sections simultaneously displayed rates and a does-not-ship warning, so confirm destination availability at checkout. A suitable PicoPSU and adequately rated 12 V center-positive power brick are separate parts.

Adds a 16 MHz 68030 to a Macintosh Plus with a compact hobbyist-buildable board derived from the MicroMac Performer.

This build requires a PGA 68030, five programmed 16V8 devices, and soldering a socket on top of the Macintosh Plus 68000. The maker does not recommend the System 7.0 GemStart driver, reports garbled or intermittent audio, and warns builders to watch the first SIMM's clearance.

Converts compatible PS/2 or AT keyboards for IBM PC and XT keyboard ports.

Retro Electronics listed one assembled converter in stock on 2026-07-25, and the open version remains available as build files. A USB keyboard works only if it implements the PS/2 or AT protocol and can use a passive USB-to-PS/2 adapter.

Adds an Apple II-compatible environment to an IBM PC through an ISA expansion card.

The author provides complete design and fabrication files but does not sell the board. This is a large full-length card with programmed logic, RAM and ROM parts, and several required cable assemblies. It also needs the original Quadlink software disk images and DOS. The clone has been tested only in an IBM 5150; the 5160 is expected to work but remains untested by the author, and faster ISA systems may fail because the software may contain CPU-dependent timing loops.

Open ATmega328P bench tester that automatically identifies and checks a broad range of vintage DRAM and 2114 SRAM.

The repository was active on 2026-07-20 and documents firmware 5.0.7. It links ready-made routes at AmiBay, Lectronz, eBay, and Tindie plus a PCBWay through-hole board, but those sellers were not independently checked for stock in this pass. Hardware is CERN-OHL-S v2 and firmware is GPLv3. Builders may use through-hole or surface-mount files and must select or build any required adapter for the exact package.

Adds 128 KB of low-power Saturn-compatible bank-switched RAM to slot-based Apple II systems.

The assembled Tindie card was out of stock on 2026-07-24 and had been sold out since March 14, 2025. The open repository provides schematics, KiCad files, Gerbers, and documentation. In an Apple IIe or IIgs this is not normal auxiliary or fast memory; only software that understands a Saturn-type card in a peripheral slot can use it.

Adds low-profile, adjustable RAMWorks-compatible auxiliary memory to an Apple IIe.

The assembled Tindie card was out of stock on 2026-07-24 and had been sold out since December 1, 2025. The open repository remains buildable. A Revision A IIe needs the card's DHGR jumper resistor or trace removed and then loses double-high-resolution graphics support. An A2Heaven VGA Scaler's long 14 MHz clock lead can cause RAM errors unless its clock connection is buffered or otherwise corrected as documented.

Adds selectable 4 MB or 8 MB of low-profile SDRAM fast memory to an Apple IIgs.

The assembled Tindie card was out of stock on 2026-07-24 and had been sold out since June 17, 2025. The repository retains hardware, programmable-logic, documentation, and fabrication sources. Select 4 MB when every byte must be DMA-accessible; at 8 MB, only the first 4 MB is DMA-compatible.

Recreates the RAMBO 256 KB memory upgrade for Atari 800XL and 1200XL computers.

The maker publishes a schematic and Gerbers but no bill of materials, and recommends the 74LS logic shown in the schematic over the HCT parts pictured on one build. Installation is model-specific. A 1200XL also requires replacing its original 64K DRAM devices with 256K versions.

Recreates an expandable Apple-1-compatible computer as either a compact single board or a set of functional cards on a backplane.

The GPL-3.0 repository supplies KiCad design files, fabrication exports, schematics, bills of materials, firmware, and assembly guidance. Builders must fabricate boards, source components, solder the computer, program its EEPROM, and load the Arduino Nano interface software. Retro Electronics had one bare backplane PCB, three bare VDU PCBs, and five bare VDU color-amplifier PCBs in stock on 2026-07-27; these are parts of the RC6502 build and do not constitute a complete kit. Early SBC revisions D and E need the documented CPU-power patch wire; the repository's current bill of materials names Revision H.

Open FPGA hardware and gateware platform in a DIP-28 package for emulating 6581 and 8580 SID chips.

The official repository provides hardware and gateware, but this bounded pass did not verify a current assembled-product seller.

Converts Sophia or VBXE RGB video to VGA inside a 1088XLD.

The project publishes schematics, Gerbers, source, and PIC12F1572 firmware, but requires a separate GBS-8200 board and mechanical installation. Firmware 1.2 is beta, high-resolution modes are untested, and its rudimentary presets do not work with every monitor. The maker notes that Sophia2 is generally the better universal VGA and DVI solution.

A buildable C128 and IBM CGA digital-to-analog video adapter with RGBS, RGBHV, and Commodore A/V pass-through options.

The repository publishes KiCad sources, Gerbers, a BOM, and printable cases for revision 1.3. The maker tested RGBI, composite, S-Video, audio, and GBS-Control output; revision 1.3 corrects the earlier monochrome pass-through error. This is not a scan converter. Use a compatible 15 kHz path such as GBS-Control or a suitable SCART converter. Never connect the C128 A/V power input and the external barrel power input at the same time. The maker found an ordinary SCART-to-HDMI box unstable in one 80-column game while GBS-Control remained stable.

Open 8-bit ISA real-time clock card for PC/XT systems without a built-in battery-backed clock.

Weird Electronics' assembled, complete-kit, and PCB-plus-programmed-SPLD options were temporarily unavailable while the seller takes a break through August 20, 2026. Aitor Gomez Garcia's low-profile version showed three units in stock on 2026-07-27 but currently ships only within Spain. A CR2032 battery is not included.

Connects a 50-pin SCSI device such as BlueSCSI V2 directly to an external Macintosh DB-25 SCSI port.

The store page explicitly said Out of Stock on 2026-07-24, but the maker repository includes assembly instructions and Gerbers for noncommercial DIY fabrication.

Family of IEC storage devices that lets supported Commodore computers access files and disk images on SD or other removable media.

Retro Lemon listed its user-port-powered C64, C128, VIC-20, and SX-64 variant in stock at GBP 34.17 on 2026-07-27, and Sordan exposed a current Buy now path for its combined SD2IEC and Tapecart variant. PolyPlay's plain external Sordan Micro device and Retro Electronics' internal board were out of stock, while the RetroFletch backplane seller was on a break. A complete open C64 SD2IEC LP hardware build is also available. Variant power, connectors, controls, and firmware configuration differ. The official firmware site says 0.x firmware is obsolete and warns that newer-dated bootloaders are not necessarily safer or better.

Reimplements SDrive around a 48 MHz Cypress PSoC ARM controller with microSD, capacitive controls, eight drives, and cassette emulation.

The repository publishes Eagle hardware files, PSoC firmware, update binaries, documentation, and enclosure models. Initial controller programming requires a Cypress KitProg-compatible programmer and the source expects the older PSoC Creator 4.0 toolchain. The latest tagged update is from 2018 and fixes FAT16, large ATR and 256-byte-sector handling, applies Hias patches, and improves SD-card compatibility; the last repository change shown is from 2022. No current assembled seller or explicit repository license was verified.

Emulates Atari SIO disk and cassette drives from microSD storage with an Arduino and touchscreen.

The Brewing Academy kit was sold out on 2026-07-24, but the firmware and build files remain public. Its kit still requires assembly and part of an SIO cable. The official project strongly recommends external power because the approximately 150 mA load exceeds the Atari SIO specification; follow its wiring instructions carefully to avoid back-powering the computer or device.

Provides open internal and currently assembled external SD-based SIO disk-emulator variants for Atari 8-bit computers.

Lotharek exposed a login-or-register-to-buy path for SD Drive Mini on 2026-07-27, and Retro Lemon also listed it with pricing. It plugs directly into SIO, uses a FAT32 microSD card and SDRIVE.ATR, and provides two buttons plus LEDs for selecting four drive slots. The separate open SDrive-Simple-II build still requires PCB assembly, ATmega328P programming, and an internal SIO connection. Its documented firmware supports cards up to 32 GB and ATR and XEX files, but not CAR, ROM, ATX, XFD, or CAS files, and it has no control for swapping disks in a multi-disk title. The former SDriveXEL assembled source and exact public build package remain unavailable.

Safely connects a Sega Mega Drive or Genesis controller to a Commodore 64, Commodore 128, or Amiga with configurable fire and jump mappings.

The open CERN OHL 1.2 project supplies design and fabrication files plus a bare-PCB ordering route. On 2026-07-30, Gotek Retro listed its assembled C64/128 and Amiga adapter at EUR 15 and AMI64 listed its assembled C64 and Amiga adapter at GBP 20. Turn the computer off before changing selectors, choose the correct computer mode, and assign each function only once. The open and AMI64 versions may need a joystick extension cable at an Amiga 600.

Open ISA card combining a two-drive floppy controller, RS-232 serial port, and optional BIOS ROM.

The repository supplies KiCad files, Gerbers, a bill of materials, and assembly documentation rather than a retail order path. Install the 5 V-on-pin-3 jumper only for a compatible PS/2-style drive; using it with a standard drive causes a short. Version 1.0 also has a documented option-ROM switch-table error.

Open ISA sound-card design using Yamaha OPL2 hardware for AdLib-compatible FM synthesis.

Retro Electronics listed the Version 1.2 bare PCB in stock on 2026-07-25. No components or assembly are included; the obsolete Yamaha sound chips can be harder to source than the common logic and passive parts.

Open Trident TVGA9000i VGA card for 8-bit ISA computers, including the original IBM PC and XT.

Use PCB version 1.1 for an original IBM PC or XT; version 1.0 needs the documented ALE rework. On version 1.1, the C17 silkscreen incorrectly says 1 uF instead of 1 nF. The project also documents a color-monitor detection workaround for newer DDC displays.

Combines a Z80 CPU, 512 KiB Flash, 512 KiB SRAM, clock, reset, and RomWBW paging on one modular card.

Tindie listed the complete Z80-512K kit without an out-of-stock notice on 2026-07-25; complete open files also remain available for both designs. The Z80-CPM store page failed extraction, so no stock claim is made for that variant. Z80-512K builders using its supervisor without a backup battery must short the battery connector as documented.

Open hardware 10/100 Ethernet card designed around a modern controller for the Macintosh SE/30 PDS.

Uses a Raspberry Pi cartridge to emulate memory, sound, cartridges, ROMs, and file-loading functions across several Commodore 8-bit systems.

The open project publishes Gerbers, BOMs, software, and case files for full-size and Zero boards. Retro-Updates' assembled Sidekick64 Zero was out of stock on 2026-07-27 and excludes the Raspberry Pi Zero 2. The maker calls the project a personal playground and warns that unsupported images, timing glitches, and unsafe cartridge combinations remain possible.

DIY RP2040- or RP235x-based replacement for one or two 6581 or 8580 SID chips, with optional FM emulation and paddle or mouse input support.

Choose the hardware design and matching firmware together. The official project documents different DAC, PWM, connector, line-output, and host-interface arrangements plus a list of preassembled sellers. Multi-SID or FM modes need the documented address-signal wires. Never power the module from USB and the Commodore computer at the same time.

Turns supported Arduino hardware and a microSD reader into a single Atari 1050-compatible SIO disk emulator.

The maker says SIO2Arduino has been superseded by SDrive-MAX and is no longer actively developed, but its GPL source and detailed wiring instructions remain online. It currently emulates only one D1: drive. A build needs a supported Arduino Uno, Mega 2560/ADK, or Teensy 2.0, a compatible SD reader, the specified SdFat library, an Atari SIO connection, and configuration matched to the chosen hardware. LCD and physical controls are optional.

Bare replica motherboards for rebuilding damaged Commodore 64 boards in four original assembly configurations.

Bob's Bits listed the bare SixtyClone PCB at USD 35 on 2026-07-30 with live revision and optional-component controls. The Tindie page simultaneously displayed a United States shipping rate and a does-not-ship warning, so confirm destination availability before ordering. Resistor, capacitor, resistor-network, power-switch, SwinSID Nano b, and GAL-PLA options do not make the base board a complete computer.

Emulates Disk II, UniDisk 3.5, and SmartPort storage from an SD card with an STM32F411.

The project README linked a current assembled eBay listing on 2026-07-27 and also publishes a complete build path. An innoelement assembled variant showed six units on Tindie, but that page simultaneously displayed a shipping rate and said it did not ship to the United States; confirm checkout availability before relying on it. Match the board revision, bootloader, and firmware: bootloader 0.15 has an Apple IIgs SmartPort problem, and boards older than Revision 3 need a trace modification for Apple IIc or IIgs use. Use a quality FAT32 SD card with 32 KB clusters. Never connect an ST-Link programmer while either USB or the Apple II powers the board.

Provides new bare analog and neck-board PCBs for rebuilding a Macintosh SE display and power assembly.

The product page offered Add to Cart on 2026-07-24. The listing supplies only bare analog and neck PCBs. There are no assembly or soldering instructions, and the vendor assumes expert high-voltage experience. CRT and mains circuitry can retain lethal voltage; this is not a beginner repair.

Recreates the 1989 Sound Blaster 1.0 with digital playback and recording, AdLib-compatible synthesis, CMS audio, and a joystick/MIDI port.

This is a self-assembly project. Follow the documented bodge resistor, MIDI jumper-wire, firmware, DMA, IRQ, joystick, and I/O-address instructions before use.

Implements Sound Blaster-compatible audio for Micro Channel systems with OPL2 synthesis and CPLD-managed bus, interrupt, and DMA logic.

Installation requires the supplied ADF and the host reference-disk configuration program. The maker warns against LS or HCT logic because it may not meet Micro Channel timing margins.

Converts a Super Nintendo controller into Atari-style direction and fire signals for tested Commodore, Amiga, and Atari computers.

This is a build project rather than a current assembled product. Use the published Atari/Commodore wiring, ground PB1 to select that mode, and program the ATmega8A with the documented firmware and fuse bytes. The maker reports successful tests on a C64, Amiga 500, Amiga 600, and Atari 130XE; the 130XE relationship is banked because that exact target is not yet in the catalog. Minimig and Amiga CD32 are explicitly unsupported.

Host-specific C64 and C128 breakouts with open eight-pin designs plus an assembled five-pin option for early C64 boards.

Retro Rewind listed the assembled eight-pin C64 version, while Commodore4ever listed both eight-pin and early five-pin C64 versions on 2026-07-30. The open eight-pin C64 and dedicated C128 variants remain buildable from board, BOM, and case files. The standard C64 board physically blocks the IEC port on a C128, so use the dedicated C128 layout there. Optional two-channel output requires a second SID or similar source wired to pin 7; otherwise both output channels carry the computer's mono audio.

Open five-board set for bringing Commodore cassette, user-port, and PET IEEE-488 connections to headers and ribbon cables.

The public repository provides revisioned PCB project files, pictures, and a GPLv3 license, but no current assembled seller is documented. Builders must fabricate the required board pair, fit connectors, and make the matching ribbon cable. The concise README does not document buffering, isolation, fusing, current limits, or a safe live-connection procedure; verify orientation and wiring and make every connection with the computer powered off.

Publishes an experimental 1024 KB plus 64 KB SRAM expansion board for the Atari 600XL and 800XL.

The author labels the April 2025 post UNDER WORK and calls it a placeholder. A KiCad archive containing the stated schematic and Gerbers is downloadable, but the page provides no bill of materials, assembly guide, firmware, electrical test results, completed installation report, or explicit license. Treat it as an unfinished engineering project for experienced builders, not a validated kit.

A source-available relay board that cuts the C64's 5 V supply above about 5.6 V.

The public repository was last updated in January 2020 and PCBWay retains a bare-board order route for Revision E. No explicit hardware license is published, so this is source-available rather than licensed open hardware. Revisions C and D require a documented bridge between DIN pins 4 and 5 for supplies that place 5 V on the alternate pin; Revision E incorporates that fix. A separate builder found severe thermal drift in an older Console5-derived prototype and called that build unfit for protection. Test any completed board's trip point and stability under realistic load and temperature before relying on it.

Open 1 MB battery-backed RAMFactor-compatible memory card with a NoSlotClock-compatible clock and ProDOS restore image.

No current assembled seller was verified on 2026-07-24, but the GW4206B hardware, CPLD, firmware, documentation, and fabrication files remain public. A CR2032 is required for clock operation, retained RAM, and the restore partition. Replacing it erases RAM and resets the clock. Disable TimeDisk's clock when another NoSlotClock-compatible device is present. The USB updater requires 64-bit Windows 10 or later, including supported Boot Camp or Parallels configurations.

Business-card-sized RC2014-compatible Z80 computer with 1 MiB of memory and integrated serial and parallel I/O.

This is a surface-mount self-assembly project with KiCad, Gerber, CPLD, and firmware documentation. Programming its MAX7000AE CPLD requires the older Quartus II 13.0sp1 toolchain because newer Quartus versions do not support the device.

Lets Atari 8-bit computers use an external PS/2 keyboard through a POKEY-based internal adapter.

The Brewing Academy versions were sold out on 2026-07-24, while MyTek publishes schematics, board files, firmware, parts information, and bare-PCB order links. A 600XL or 800XL uses the TK-II-PB-R installation. Expect soldering and possible case modification; an unsocketed POKEY must be desoldered and fitted with a 40-pin socket. The Stereo version needs a second genuine POKEY and external amplification for its line-level output.

Recreates a 25 MHz 68040 accelerator for the Macintosh LC, LC II, and Color Classic.

This is a noncommercial self-build project with no assembled purchase path. The XC1736 configuration PROM at U15 must be programmed with reset polarity set high, and the complete build requires an XC3030 FPGA plus the listed 68040 and support parts.

Modern replacement power-supply boards for Macintosh SE and SE/30 Apple, Sony, and ASTEC enclosures, with assembled, DIY, Pico ATX, and separated-rail options.

On 2026-07-27, the DIY AC/DC board was $22 with four left, the assembled and DIY Pico ATX boards were $89.99 and $16.99 with two left each, and 4XDC was $170 with two left. The $129 assembled universal AC/DC board had been sold out since May 27, 2026. Check the selected architecture, PSU-enclosure variant, parts included, and destination availability before ordering.

Improves Atari 8-bit analog video and corrects overscan for modern displays.

The Brewing Academy configurations were sold out on 2026-07-24. MyTek publishes the current UGV-II schematic, bill of materials, PIC firmware, and Gerbers. The 0.8 mm main board requires assembly and PIC programming. A normal installation is nearly solderless at the GTIA, but routing video to the stock DIN connector can require a few motherboard solder points.

Adds firmware-controlled RGB lighting inside a C64 case fitted with an Ultimate64 mainboard.

Official construction and pinout documentation and multiple printable mounts remained downloadable on 2026-07-30. COREi64's assembled shop is closed for updates until Fall 2026, so no current prewired retail kit is claimed. Use firmware 1.10 or later and the exact 5 V wiring. The official guide warns that shorting 5 V to ground can burn a board component and applying 5 V to an FPGA pin can damage the FPGA.

Experimental C64 replacement motherboard with three SID sockets, optional internal storage and sound modules, ROM switching, and extensive test points.

On 2026-07-30, UNI64 listed the bare v4 PCB at EUR 32.50 as a three-week preorder and the READY+ board at EUR 345 with a five-week order lead time. READY+ includes standard logic, the 8701, and 64 KB RAM but excludes all named Commodore-specific chips and the required 12 VDC 2 A supply with a 2.1 mm inner-diameter barrel plug. Optional Pi1541, MIDI, FM OPL2, and SSD hardware is not included. The bare page labels its feature list as Version 3 even though the product and files are v4; the linked v4 info PDF remained unreadable after the required retry under WF-071, so confirm version-specific assembly details from the supplied documentation.

Connects modern Bluetooth gamepads and, on selected models, mice to Commodore, Amiga, and Atari computers.

The official C64, A500, and 800XL Tindie pages were out of stock on 2026-07-30, although the project marks those models active and supported. CBMretro had equivalent cased C64/C128 and A500/A1200 hardware available at EUR 41.90; the original designer does not support third-party builds. Open hardware, firmware, and documentation remain available. The guide's original Unijoysticle tile is folded here as the retired WiFi predecessor: it needed a separately powered ESP8266 receiver and phone or desktop client, unlike the Bluetooth successor.

Open EPROM cartridge board for making single-ROM, switchable multi-ROM, and diagnostic cartridges for the C64 and C128.

The repository provides board revisions, fabrication files, and documentation. A working cartridge still requires a PCB, components, a correctly programmed EPROM, and configuration appropriate to the selected ROM images.

Bare replica of the later seven-pin-power VIC-20 Assembly 250403 motherboard.

Bob's Bits listed the bare Vicky Twenty PCB at USD 35 on 2026-07-30 with a live color selector and optional resistor, capacitor, and power-switch controls. The page exposed no destination-specific shipping decision until a country is selected. The base product is an unpopulated board; none of the optional packs supplies every component or custom chip required for a working VIC-20.

DIY Commodore 64 wireless-interface project built around a MicroView display.

The project files remain downloadable, but no current assembled seller was verified. The readable top-level project material does not specify the computer connector, supported online services, transfer speed, or complete present-day parts requirements, so builders should inspect the repository before committing to a build.

Documents period DIY memory conversions that give an Atari 400 48 KB plus a banked 16 KB or an Atari 800 a 288 KB SuperRam configuration.

These are historical, invasive board-level modifications rather than current kits. Both require extensive disassembly, trace cuts, soldering, stacked or perfboard logic, and staged electrical testing. The authors release the instructions for public use with attribution. The Atari 800 text lists six 41256 DRAMs, while human review found only one 41256 in its rough circuit sketch. The contradiction remains unresolved: do not treat the Atari 800 parts list or sketch as an authoritative build package without reconstructing and checking the circuit.

Adds an internal CompactFlash hard drive to the 1088XEL through its MPBI expansion interface.

Both variants have public fabrication material, and the Rapidus board adds KiCad source. Use only the specified Texas Instruments 74F-series logic. The interface needs flashjazzcat's special 1088XEL Ultimate 1MB BIOS, replacing the original SIDE PBI and loader. Keep the IDE cable under 10 inches when practical. The maker does not guarantee every CompactFlash card and reports the best results with genuine SanDisk cards rated at 30 MB/s or less.

DIY 8-bit ISA CompactFlash adapter that provides mass storage and supports an XT-IDE BIOS extension ROM.

The project supplies build files and documentation rather than a direct retail order path.