Projects

MACSIMM - Programmable ROM SIMM for Mac SE/30, IIfx and IIsi

Submitted by GG on Thu, 05/25/2017 - 18:46

MACSIMMThe Mac SE/30 was the fastest of the classic compact black and white Macintosh computers. It featured a 16MHz 68030 with 68882 FPU and a 32-bit memory interface and supported, albeit not officially, up to 128MB of RAM. Unfortunately the SE/30 ROM contained some old code that used 24-bit addressing making it 32-bit dirty. Many classic computer enthusiasts make their SE/30 32-bit clean by installing a Mac IIsi ROM SIMM. These are nowadays quite rare and difficult to find.

Filed under: 
Retrocomputing
Apple

GRAM/512S - 512KB geoRAM clone for Commodore 64/128

Submitted by GG on Tue, 05/02/2017 - 02:25

geoRAMThe geoRAM is a 512KB memory expansion for the Commodore 64 and 128 designed by Berkeley Softworks for use with GEOS. While not as fast as the Commodore REU due to its lack of DMA capabilities, it still provides a significant performance boost. GRAM/512S is a geoRAM compatible cartridge based on a single 512Kx8 SRAM.

Filed under: 
Retrocomputing
C64

E2R16 - 27C400 programming adapter for Minipro TL866

Submitted by GG on Sun, 03/27/2016 - 00:52

MiniproThe Minipro TL866 is very popular among hobbyist because of its low price and ease of use. Its list of supported chips is however somewhat limited compared to more expensive professional programmers. The E2R16 adapter adds support for the ROM pinout compatible EPROM of the 27C400 series which are compatible with Amiga computers and many arcade machines.

Filed under: 
Retrocomputing
Amiga

A520HD - Commodore Amiga RGB to HDTV Component Adapter

Submitted by GG on Fri, 01/15/2016 - 13:33

A520HDThe GGLABS A520HD is the HDTV equivalent of the classic Commodore A520 TV modulator. Instead of encoding the Amiga video signal to a low quality composite output it converts the RGB output to a high quality YPbPr signal compatible with HDTVs with a component input. The A520HD connects to the Amiga 23-pin video port and is powered directly from the system.

Filed under: 
Retrocomputing
Amiga

GLINK232 - UART cartridge for Commodore 64/128

Submitted by GG on Tue, 12/01/2015 - 18:01

glink232Both the commodore 64 and the 128 have a software UART implementation that limits the useful speed to 2400 bauds. To work around this limitation Dr. Evil Labs and later CMD produced the SwiftLink232 and Turbo232 cartridges based on the 6551 ACIA chip. Both of these have been out of production for a very long time. GLINK232 is a modern replacement for the swiftlink232 allowing the commodore 64/128 to communicate at speeds up to 38400 bauds.

Filed under: 
Retrocomputing
C64

6-10W boost LED driver

Submitted by GG on Sun, 09/21/2014 - 19:30

ssr01 pth versionHigh power LEDs require a constant current power supply for optimal operation. GLED1 is designed to drive 10W white LEDs (9 diodes in series) from a 12V or 24V supply. The board can be used down to 3V but the maximum output power will be reduced in this case. The design supports discrete level dimming using a two or three way switch or continuous control using a PWM signal. The design is based on the ON Semiconductor NCP3065/3066.

Filed under: 
Vreg

PWR01 - Small and Efficient AC-DC Flyback Converter

Submitted by GG on Thu, 11/15/2012 - 18:06

PWR01 TopDespite the significant advantages in size, weight and efficiency, switching AC-DC supplies are not very common with hobbyist due to their complexity and scarcity of ready to build kits.
PWR01 is a low power (~6W) universal voltage (100-240V) isolated AC-DC flyback converter based on the ST Microelectronics VIPer17. Either 5V or 12V output can be obtained using an off the shelf transformer.

Filed under: 
AC
Vreg

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