The 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.
The 80 column output of the Commodore 128 is the same digital RGBI used by the original IBM CGA graphics adapter. Unfortunately nowadays is quite difficult to find a monitor with the suitable RGBI input. The CGA2RGB adapter will convert the TTL RGBI to analog RGB suitable to be connected directly to a 15KHz capable RGB monitor or to the popular Gonbes GBS-8200 VGA converter.
Active termination is required to get newer higher performance drives working on vintage computers. Unfortunately both the Amiga and older Apple computers use a DB25 SCSI connector which makes finding a suitable terminator quite difficult. GTERM25 solves this problem providing a high performance active terminator with a DB25 connector and SCSI diagnostic LEDs.
The apple IIgs is the most advanced computer in the Apple II series. Equipped with a 65c816 8/16-bit CPU with 24-bit address space it could address up to 16MB of memory. The original rom 01 model shipped with 256KB of fast RAM, the revised rom 3 shipped with 1MB (both had an additional 128KB of standard RAM and 64KB of sound RAM). RAMGS/4 is a newly designed 4MB SIMM based memory expansion card for this great classic computer.
The 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.
RS232 monitors are quite common but most of them use the standard good old DB25 connectors. The majority of the RS232 ports in use today however use the smaller DB9 connector. This forces the use chains of adapters to get the commercial monitor/breakout boards working. The GGLABS T232 solves the problem by providing native DB9 connections.
The 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.
Both 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.
The apple IIgs, like many computers from the 80's and early 90's, has a analog RGB output at a 15KHz horizontal frequency (same as NTSC/PAL). The majority of modern monitors and TVs will not sync to anything below 31.5KHz on their VGA input. If you have a TV with a SCART connector it is possible to wire the RGB directly to the TV. Most TVs in USA, however, use the YPbPr component instead of SCART making a direct connection not possible.
High 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.