He uses a little CNC mill to create wood mold masters for silicone molds which he casts polyurethane parts in. It seems to work well.
"Both the original Omnibot and this revised approach feature a novel reconfigurable drivertrain, which enables the robot to perform on-the-spot 360° turns and to effortlessly alternate between forward and sideways motion. As opposed to most other omnidirectional designs, Omnibot can do so without losing registration with the environment, and without relying on exotic and expensive components. In fact, it uses just three extremely cheap brushed motors and four regular wheels."
Nice interview with Ian Lesnet of Dangerous Prototypes. I haven't heard much about Dangerous Prototypes in the last few years... I hope he's still doing some kind of open hardware somewhere.
Good overview of how probe parasitics affect measurements.
big list of electronics youtube channels and related resources
A short article on the Hackaday blog about one of my projects
The Commodordion is an 8-bit accordion primarily made of C64s, floppy disks, and gaffer tape. Article includes a video of the Commodordion in action.
A 6502 game console (h/t hackaday.com)
Directly controlling an OLED display via HDMI.
Doug Ford's classic 2009 article on how oscilloscope probes work including how 10x probes use lossy coax to improve frequency response.
Jay Carlson's excellent write up of the very inexpensive Padauk microcontroller's.
I enjoyed this presentation by Ted Yapo about his DIY sampling scope.
Writeup on an effort to design and produce 200 little flyback converters (meant for powering Nixie tubes).
Successfully executing a replay attack against a wireless key fob using inexpensive hardware and GNU Radio (based on Samy Kamkar's original hack).
This is an entire PC-compatible single-board computer implemented with an 8051 microcontroller (!) running an x86 emulator.
I've been able to find very little about the Appotech AX-2005 System-on-chip, just the first page of its datasheet (it runs at 125Mhz):
This TTL computer looks like an interesting design:
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It implements an 8-bit RISC CPU with an 8-instruction CPU using a surprisingly small number of chips: just 36 standard TTL chips, a ROM, and an SRAM chip.
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The VGA output is generated entirely in software with no additional graphics hardware (other than a resistor DAC). User code runs only during the hsync and vsync periods.
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The ROM kernel takes care of all the VGA timing and runs a virtual machine which presents itself as a 16-bit CPU and includes an interpreter so programs can be written in a high level language.