If you have an interest in audio there are plenty of opportunities for home construction of hi-fi equipment. You can make yourself an amplifier which will be as good as any available commercially, and plenty of the sources you might plug into it can also come into being on your bench.
There will always be some pieces of hi-fi equipment which while not impossible to make will be very difficult for you to replicate yourself. Either their complexity will render construction too difficult as might be the case with for example a CD player, or as with a moving-coil loudspeaker the quality you could reasonably achieve would struggle match that of the commercial equivalent. It never ceases to astound us what our community of hackers and makers can achieve, but the resources, economies of scale, and engineering expertise available to a large hi-fi manufacturer load the dice in their favour in those cases.
The subject of this article is a piece of extreme high-end esoteric hi-fi that you can replicate yourself, indeed you start on a level playing field with the manufacturers because the engineering challenges involved are the same for them as they are for you. Electrostatic loudspeakers work by the attraction and repulsion of a thin conductive film in an electric field rather than the magnetic attraction and repulsion you’ll find in a moving-coil loudspeaker, and the resulting very low mass driver should be free of undesirable resonances and capable of a significantly lower distortion and flatter frequency response than its magnetic sibling.
At frustratingly regular intervals, the debate around gun control crops up, and every time there is a discussion about smart guns. The general idea is to have a gun that will not fire unless authenticated and authorized. There’s usually a story about a young person who invents a smart controller and another company that is struggling because they just can’t get “Big Guns” to buy into the idea. We aren’t going to focus on the politics; we’re going to look at whether the technology is realistic, and why a lot of the news stories about new tech never pan out.
Let’s start with an example of modern technology creeping into established machines: the car. These are giant hunks of metal with nearly constant explosions, controlled by sophisticated electronics that are getting smarter and more connected every day. Industry is adopting it with alacrity, and the vehicles are getting more efficient and powerful because of it. So why can’t firearms?
Many of us have enjoyed building electronic projects that come not from our own inspiration or ingenuity but from a ready-made kit. It makes sense, after all in buying a kit you should receive a tried-and-tested design that you can assemble without some of the heartache associated with getting a self-designed project right. And though in recent years the barriers to entry into the professional PCB market for small projects have lowered significantly, there is still an attraction to a kit that comes with a decent PCB and case.
If you start your electronic odyssey through kit-building, you gain more than a set of electronic projects. You learn about the circuits you build, and you gain a feel for how a well-designed project should go together. Eventually this feeds into your own projects, and in time you are producing builds that equal or surpass those you can buy as kits.
From the point of having a nicely executed project to that of wondering whether it too could be sold as a kit is not a huge step. This is the first of a series of articles that will examine the kit manufacturing process from project to customer, and will with luck deliver some insight to those of you who have always wondered whether you could make it as a kit vendor.
Wood. Humans have burned it for to heat their homes for thousands of years. It’s truly a renewable source of energy. While it may not be the most efficient or green method to warm a space, it definitely gets the job done. Many homes still have a fireplace or wood burning stove for supplemental heat. For those in colder climates, wood is more than just supplemental, it’s needed simply for survival.
The problem with firewood is that it doesn’t come ready to burn. Perfect fireplace sized chunks don’t grow on trees after all. The trees have to be cut up into logs. The logs must be split. The split wood then needs to dry for 6 months or so.
Anyone who’s spent time manually splitting wood can tell you it’s back breaking work. Swinging an 8 pound maul for a few hours will leave your hands numb and your shoulders aching. It’s the kind of work that leaves the mind free to wander a bit. The hacker’s mind will always wander toward a better way to get the job done. Curiously we haven’t seen too many log splitting hacks here on the blog. [KH4] built an incredible cross bladed axe back in 2015, but that’s about it.