astronomy Photo of Comet Neowise Made it over to Mt. Hood to see Comet Neowise and captured this photo. The Portland city lights are visible on the horizon. Comet Neowise. Canon 6dmkii, 24mm prime lens
hamradio Home Antenna Grounding I recently installed an end-fed wire antenna running from the apex of my garage into a large maple tree in my backyard. I want to get the best performance I can from the antenna and also take the appropriate precautions to operate safely and protect my equipment.
Yeasu FT301D Restore - Part 1 When I first got my ham radio license I purchased a Yaesu FT-301D from another amatuer radio operator on Craiglist. I enjoyed using the radio, but over the years I've ended up using
retrogaming MiSTer Case I've recently been interested in FPGA-based gaming systems. These systems implement the hardware of gaming systems on a programmable FPGA to achieve very accurate "hardware emulation" of the platform. A recent popular example
hamradio Loop Antenna Copper Jumpers I am planning to machine some copper jumpers to go between the copper loop and the vacuum capacitor. These can be soldered (or brazed) to create a solid connection with very low resistance.
cnc LCD Control Board for SX3 Mill The LittleMachineShop control board replaces the button board built in to the mill, so when the spindle control board is connected the buttons and LCD built in to the mill are no longer functional. I designed a drop-in replacement for the button board to help add back some functionality.
hamradio Full Disk Images of Earth from GOES-17 Geostationary satellites maintain their position relative to earth. This means a parabolic dish can be pointed at the satellite and receive continuous downloads.
photography Astrophotography, Part 1 Astrophotography used to be a hobby of mine and I would make it out with my camera a few times a year. Over the last few years I haven't prioritized this hobby, but
photography Soap Film Photography After a few photo and brainstorming sessions, we ended up with a repeatable setup to capture the kinds of images we wanted. In this post I hope to pass on some of the things we learned and share some of the resulting images.
loopantenna Loop Antenna - Initializing the TMC2130 Continued from part 4. Now that I can read and write across the SPI interface I am going to write an initialization routine for the TMC2130. Fig 22.1 and 22.2 in
STM32 Loop Antenna - SPI Read and Write Continued from part 3. Now that I have confirmed the stepper driver is working properly, I want to establish SPI communication for configuration and status readback. This will be especially important to enable
hamradio DDS RF Signal Source In 2017 I designed a local oscillator board which can be used to generate an RF signal in the HF range (< 30MHz). I hope that this can become the building block for
cnc Shopfox M1111 Mill Conversion - Intro In 2017 I acquired a Shopfox M1111 benchtop mill. It has an intermittent issue with the spindle motor, but is otherwise mechanically sound. This mill is very similar to the Grizzly X3 mills
loopantenna Loop Antenna - Motor Control Part 1 Continued from Part 2.I am starting to work on the automatic tuner for the magnetic loop antenna. I will implement the various functional blocks in the following order:1. Motor control and
loopantenna Loop Antenna - Assembly and First Test Picking up from part 1. Today I finished assembling the loop antenna and ran some tests on it for the first time. The results look great so far and after this I'll be
Oddwatt Amplifier Assembly In 2016 I built a sound system including speakers, preamplifier, subwoofers, and amplifier. I chose a tube amp design based on the "Oddwatt" design by Bruce Heran. If you want your own tube
loopantenna Loop Antenna - Annealing Copper Continued from Intro. Many people assemble their loop antennas using copper pipe and 45 degree angle connectors to form an octogon. This approximates a circle well enough, but introduces some electrical resistance to
Infrared Photography The sensors inside many consumer cameras on the market today are sensitive to infrared light. This isn't normally desireable, so manufacturers add an infrared-blocking filter in front of the sensor. It is possible
4pi 4PI Speaker Build This is a build log for my 4PI speakers. These high-efficiency speakers have a 15" woofer and a horn-loaded tweeter.
audio 4PI Speakers and Oddwatt Amplifier In 2016, I set out to design and build a sound system for our house. Going into the project, I knew I wanted to build a tube amplifier. I'm not much of an
art Droplet Photos - Part 2 In Part 1, I showed my setup for taking water droplet photos by using an eyedropper and an IR emitter/receiver pair. After learning from that setup, I created a fully-automated droplet setup
art Droplet Photos - Part 1 Droplet photography is interesting to me because it combines two interests of mine: photography and electronics. I've done multiple photo sessions over the years with different technical methods of synchronizing the shots. In
highvoltage High Voltage Experiments Flyback transformers are a great tool for experimenting with high voltage. These transformers were commonly used in CRT monitors/televisions and are designed to generate the high voltage necessary for the operation of
moveo Robotic Arm - Part 2 - Assembly In part 1, I shared some of my notes about the BOM for the Moveo robotic arm. In this article I'll share some pictures of the assembly.All of the plastic parts on