The SIDKick pico ("SKpico") is a drop-in replacement for the SID 6581/8580 sound chips in the Commodore 64 and 128 computers. It has been designed as an inexpensive alternative to other replacements while not making compromises regarding quality. It consists of a simple interface board and a Raspberry Pi Pico (or compatible clone). The emulation is based on an extended version of reSID 0.16, and includes a few additional features.
Emulates the 6581 or the 8580 in single or dual SID mode. Has a built-in configuration menu that is accessed with a BASIC command (SYS 54301
for the c64, SYS 54333
for the c128). Supports stereo output if you hook a DAC up.
Uses surface mount components so this is not a project for the inexperienced or the faint of heart.
The RAD Expansion Unit is a cartridge/expansion for the C64 and C128 using a Raspberry Pi 3A+, 3B+ or Zero 2 to implement the actual functionality. Currently it emulates a RAM Expansion Unit up to 16mb (compatible to CBM 1700/1750/1764 REU, CLD Super 1750 Clone, CMD 1750/1750XL) and a GeoRAM/NeoRAM memory expansion up to 4mb. It also features a menu to browse, manage and launch REU- and GeoRAM-images, NUVIEs, and PRGs. The RAD is designed to not only emulate existing extensions, other things that have already been tested (but not yet included here) are, for example, MOS 6510/8500 emulation (incl. turbo mode) or using the RAD as a (co-)processor (in fact the menu runs on the ARM CPU only).
RAD's functionality is entirely defined by software. The connecting circuitry is quite simple and does not include any programmable ICs and is thus easy to build.
Among other devices, Keelog sells a line of replacement power supplies for retro computers, from the Commodores to Amigas to Ataris. They are all brand new designs engineered with longevity and safety in mind.
They sell replacement parts, refurb kits, and some upgrades for classic computers. Their official documentation is in a wiki: https://console5.com/wiki/
A company that makes and sells components, new hardware, and software for classic 8-bit computers.
This website has a good archive of abandonware and some interesting web apps, like an online disk editor and visualizer for .d64 disk images.
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Commodore Free is a free-to-download Commodore enthusiasts' zine that includes everything from new software releases to howtos, reviews, hardware mods, and more. Every retrocomputing afficionado should give at least one issue a read.