Projects

ISO01 - Compact low voltage isolated power supply

ISO01 A00While working in the lab it's often useful to have a small isolated power supply handy. Depending on the circuit configuration, ISO01 can generate galvanically isolated unipolar and symmetric voltages from a single 3.3V or 5V rail. The circuit is based on the Texas Instruments SN6501 transformer driver and uses an easy to obtain off the shelf transformer.

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GZ/80S - 20MHz Z-80 PCPI Applicard compatible Apple CP/M card

GZ80 B00The PCPI Appli-Card was the first single board computer style CP/M card for the apple II. It featured a 6MHz Z-80 CPU paired with 64KB of RAM and 2KB of ROM. Thanks to the high clock and zero wait states DRAM accesses the card performed almost 3 times as fast as the Microsoft SoftCard. The GZ/80-B00 is a new implementation of the PCPI card with a 20MHz Z-80 CPU and 512KB of static RAM.

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GTERM25 - DB25 Active SCSI Terminator with diagnostics LEDs

GTERMActive termination is required to get newer high 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.

GS2HD - Apple IIgs RGB to HDTV Component Adapter

GS2HD D00The 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.

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SSR1/A - Dual AC Solid State Relay Arduino Shield

SSR1A Many MCU applications use electro-mechanical relays to control AC loads. While this is an excellent solution for occasionally turning on/off a load, it is not suited for frequent switching or PWM applications. SSR1/A is an opto-coupled solid state relay that can control two AC loads in a arduino shield form factor.

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NANOBUG - Buttons and USB UART for NVIDIA Jetson Nano

NanobugThe NVIDIA Jetson Nano is a great device and its choice of I/O is ideal for user space development. If you are a kernel hacker, however, you will soon feel the need for serial console and a reset button. If you want to hack the bootloader you will also need a recovery button. The Nanobug integrates a UART to USB and buttons into a little board that plugs directly into the nano developer kit.

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UNICART - Universal Commodore 64/128 Cartridge

ramgsAfter we developed the UNICART/D many customers asked for a more compact version of the cartridge without the pass-through connector. The board uses one standard PLCC32 flash ROM up to 4Mbit. In C64 mode 8K, 16K and 16K Ultimax cartridge modes are supported. In C128 mode both 16K and 32K cartridges are supported.

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F2R16 - Flash based ROM Replacement for Amiga Computers

F2R16The Amiga, like many other computers of the late 80s, uses 16-bit wide mask ROMs to store the machine firmware. Unfortunately, the pinout of these ROMs is incompatible with the JEDEC defined EPROM pinout. Memory manufacturers produced "ROM compatible" EPROMS like the 27C400 to allow development and quick turn manufacturing. These EPROMS are however becoming quite hard to find and still require a UV lamp to erase the chips. F2R16 brings all the benefits of modern flash memory technology to any platform designed to use these obsolete devices.

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