This is the first post on my power supply build. Also see part II and the Circuitmaker project page.
An adjustable bench power supply has been on my list of things to build for quite a while. A linear supply should be relatively simple to design, with the added bonus of being a useful thing to have around. My goals with this project are to design and build a slightly more complex system than I have in the past, to lean to use PCB layout software and to actually get a PCB designed and manufactured. I wanted to design it from scratch, rather than using an adjustable 3 terminal regulator or a controller chip with everything built in – this is supposed to be a learning experience more than anything else.
My requirements are:
0-30V adjustable voltage
0-2A with current limiting.
Separate fixed 5V output for powering digital circuits.
This post is going to cover my first impressions of using Autodesk’s Fusion 360 CAD program from the point of view of someone who is completely new to CAD. Several months ago I bought myself a 3D printer (a Printrbot Simple – hopefully I’ll do a post on this in the future) partly as an impulse buy, partly because I’ve always been curious about them, and partly as an excuse/reason to learn how to use CAD to design parts.
Cleaning out the garage I found/rediscovered some brass sheets which have been sitting there for quite a while, so my first thought was to attempt etching them to make some art. A quick internet search revealed two options, chemical acid etching or electrochemical etching. I decided on the electrochemical route because it seems safer (no nasty acids) and cooler (who doesn’t love a battery with wires running to electrodes in a bath of blue water?). I’ll start with a teaser photo of the results of this first attempt, and then go into some details.
Gypsum, for those who are not in the know, is CaSO4 – calcium sulfate (we can thank dear Lavoisier for his nice nomenclature). It’s in your water, to varying degrees, depending on where you live. Locations with ‘hard water’ typically have much higher concentrations of it that Sydney, which has quite soft water.
Why the interest in the chemical composition? Well, it all starts with a beer called pacific ale. Or more specifically, various attempts to replicate it. From dry hopping, to last minute of the boil and rapid chilling, to proposing various bits of complex machinery, no one that I know has yet managed to replicate the delicious Galaxy (passionfruit) hop aroma of Pacific ale. So how do they do it?
Having caught the Brewing bug, I decided that the sour simply wasn’t enough brewing for this month, and figured I’d add another beer to ferment. An added bonus was the potential for there being even more deliciousness to drink. Of course, this left a pressing question – what should I brew? Not one to be restricted by my own lack of experience, I decided it, like the sour beer, had to be a little strange.
Feeling a little sorry for our demijohns, now empty of their meady goodness, we decided we should fill them with something else. Naturally, it couldn’t be anything normal, but rather something novel and untried. We ended up settling on favourite of ours – sour beer! For those who don’t know, sour beer is a style of beer that is (as the name suggests) sour. Some examples of this are Lambics, Gueze, and what the Yanks call ‘Wild Ales’. For an added bit of funkiness, we decided that we’d also use a Saison-ish yeast, which should add some additional funky flavours.
Having endured the long, difficult, indeed tormenting wait we finally reached the stage where our mead could be released from its glassy confines… and placed in new glassy confines. That’s right – its bottling day. Of course, no bottling would be complete without a surreptitious tasting of the wares. Or for that matter, without delicious food, good company, and a new beer to fill up the glassware that the mead was liberated from. So we set aside a Saturday of the long weekend, I brought the mead out of storage, and we went through the slow process of bottling.
After several months of planning and a trip to Cape York and the US getting in the way, we finally got around to making our first mead.
The process seems simple enough, mix honey and water, add yeast (and nutrient) and let it do it’s thing for a year or so.
However, the aim was to have something which will be drinkable next winter (about 8 months away) we we ended up deciding on doing 2 meads, a slightly weaker, drier one which should be ready by winter, and a stronger, sweeter one which might have to wait until next year.
