After a week delay while the United States elected an authoritarian misogynist xenophobe (more on that in another post), CCP games will be releasing one of the most fundamental player-focused changes in EVE Online; free-to-play in the form of Alpha Clones. This is a critical inflection point in the history of the game I first picked up in 2003, as an alternative to Earth and Beyond MMO which was on its downward spiral. Either the F2P option will be ignored and EVE will not grow, or EVE will grow faster than ever before. Read more

First things first, we need to figure out how to drive and read the spectrometer. There are two key diagrams to consult - the suggested application and the timing diagram. The application diagram shows several key signals, some of which the meaning isn’t clear at first. After reading through the rest of datasheet, you can generally make out the following pins: Video - the spectrometer is like a 2d camera - it is an image sensor in a line after all. Video represents the actual output, as an analog signal, of the sensor. Gain - an input, to select the gain CLK - A clock input ST - A start trigger EOS - an end of line/scan indicator - when this signal changes, you reached the end of the sensor Now, the timing diagram: Read more

Hi! You may remember me from other threads like LEDBrick DIY puck and high density stars, plus drivers (now available on blueAcro.com and the Apogee sensor PAR interface board. Many moons (months) ago, I dropped some money into a GroupGets buy for a pair of Hamamatsu Micro-spectrometers. They can resolve light intensity between 340-780nm in up to 15nm increments. They are not cheap ($180 on groupgets, qty1), but are a lot cheaper than other commercial pre-packaged light spectrum units that employ an actual spectrometer (and not a coarse approximation using an RGB light sensor). The actual absolute light intensity level is not specified (designed for relative or ratiometric measurements), so it likely wouldn’t make a good PAR meter without a ton of calibration, assuming it had any repeatability of output. Read more

I spent some time mocking up a case for the lights. I’m not totally happy with the side panels yet (more on that later), but a quick walk through the process: Read more

Nearly 6 months later, and after back-burnering the project multiple times, I’ve made some significant progress on the LEDBrick aquarium light. In the space between blog posts, I’ve: Received a round of metal-core PCBs for the LEDs. Designed an 8 channel driver board based on the L3414, a different sketch from the original planning Machined a single heat sink, and did test mounting of the emitter board. Populated one emitter board. Did thermal testing Built a single driver board and did a full integration test. Incomplete GitHub sources All of these designs are considered Open Source Hardware under the CERN license, and can be fetched from GitHub. The design files are likely incomplete, but will be updated as progress is made. Read more

Service Discovery, to use the basic definition, is the mechanism in which services, residing at a non-static address, can be found on a computer network. There are, in a basic nutshell, three types of service discovery, modeled after how they offer their service endpoints to the clients. This set can be reduced to two types in most real world scenarios. Service discovery systems are designed to return endpoints, a list of one or more logical host and/or host:port or even URL lists. These endpoints are generally in a group colloquially known as a serverset. Endpoints are also considered ephemeral - they can be de-registered at any time due to failing health checks, or other network events, including an intentional de-registration due to service shutdown. Read more

This design has been on my back-burner for quite awhile, but its time to write it up and continue pressing on. I really like reef aquariums. I currently have a (modest) 90 gallon system, which has livestock dating back to when I started keeping salt-water systems in college (circa 2004). How I managed to actually afford keeping a salt-water system in college is beyond me, but things have progressed nicely. Read more

As part of an effort to share more designs, I’ve decided to start writing a continuing series of blog articles on my hardware design efforts. This first article covers the NixieBoost of a NixieView. Read more

I got this unit for free recently, and decided to do a teardown for all fans of various vintages of test equipment. It is functional, but the buttons on the unit are absolutely terrible (hard to push, don’t stay pushed, etc etc). What follows is a picture narrative. The inside gets the “whole lot of nothing” award, presumably for the battery option: Power supply, note the internal voltage range switch: Read more

So, you have a Supermicro server somewhere remote. Thats cool, they have a nifty IPMI module (either bridged to the primary interface or on a separate port). One of the features is a remote IP-KVM over what is mostly VNC. Of course, you have a complete distrust of anything embedded, so your IPMI is on a separate LAN/VLAN. You also don’t have a VPN to this IPMI LAN, because thats a lot of work for something that you’ll never use, and everyone just uses ad-hoc SSH tunnels anyway, right? Except, you are Supermicro’s IPMI KVM thing (which is really made by a company called ATEN). That means: Read more