(no subject)

[ewt]

I have been taught some fairly basic stuff by martling. I had to do algebra again, which was not too bad, and arithmetic, which was incredibly horribly slow (I'm told most people use a calculator for such things but I really ought to get better at arithmetic anyway). I think I grok most of it now, though, although I'm still a bit hazy on transistors. I think they might make more sense when they're put together with other bits.

martling also gave me a soldering iron to get me started. shevek has loaned me a copy of Malvino from aaages ago (presented to him in 1993), but I think it's a bit beyond my understanding so far, it seems to assume you've done some basic electronics already. I'll look at the websites suggested as well, but books are useful too.

I need a thing called a breadboard for making sure things work before sticking them together.

I need 1x first project. Difficult. I have various materials and things to hack apart, and various toys I wish to build.

[A] I have 100 superbright UV purple LEDs, bought off eBay a few years ago. I'd like to make these into some pretty boot-cover things at some point, although it would be great to have some of the LEDs left over for other things. Possibly a sound-to-light sort of thing so they would be a graphic equaliser, possibly some sort of thing so when I stamp they light up. Challenges: waterproofness, making something that can fit over my boots without b0rking, making the things not so fragile that they fall apart if someone accidentally kicks my boot on the dance floor (it's happened before, it'll happen again). Variations include light-up hairfalls or arm bands; the arm bands might be easiest really.

[B] I'd like to make a decorative door sign for my bedroom door, I had one of these at Aprey Gardens only it did not light up, it was made of various bits of dismantled keyboard and other bits and bobs (glow in the dark beads stuffed inside fluorescent coloured straws, nail varnish, part of an old computer mouse). This doesn't necessarily have to be electronic at all, but I had imagined it as something that could have an indicator light for when I'm in, when I don't want to be disturbed, and so on. A bit extraneous now as I only have the one housemate and I don't really feel like he intrudes on my privacy at all, also it's a bit of a waste of batteries. But once, I had big plans for this all-singing, all-dancing door sign. It wouldn't have to be waterproof or particularly durable, but I'd want to spend quite a lot of time on the aesthetic aspects of the design.

[C] There isn't a number on the front of the house I live in, and it would be quite nice to use some of the LEDs to make a "40" so people can find my place in the dark; alternately, having the LEDs light something white with the "40" in dark would work well. If this can be solar-charged, and have a switch inside the house for to turn the light on and off, so much the better. Traditionally I've helped people find my place of residence by hanging glowsticks in the window, and I could keep doing that now I have a Krill lamp again, but something that's already there would be good too.

[D] I have one solar battery charger. It takes a while, and isn't really suitable for use in winter. I'd quite like to make another one, possibly with another solar panel, but also possibly by using the 12V solar panel I already have. I suppose finding a 12V battery charger with a car cigarette lighter attachment would be the easy way to do this, but that way I don't learn anything about how battery chargers work. I want to make sure it won't overcharge the batteries and let them go all 'splodey, and I want to make sure that when it's dark the batteries won't discharge. The latter is fairly trivial if you use a diode but I'm not sure how the first bit works. And hey, I'd have another battery charger, and could stop using the lecktric plug-into-the-wall ones. Possibly adding a wind-up bit to this would be neat.

[E] I'd quite like a wind-up/solar all-singing, all-dancing device that can be a radio, a torch, and a mobile phone charger. And maybe a battery charger as well, if there is space in the case.

[F] A Faraday flashlight.

[G] Some sort of pretty purple clock with the LEDs. I don't like digital display clocks, though, I much prefer analogue in terms of reading fast. Something like this would be quite fun, though.

[H] Some suggestion from one of you lot.

What would be involved in these projects? I know [E] is going to take longer than some of the others, and maybe I should be going for a small win here, especially since I have next to no experience with soldering.

Comments

[ewtikins.livejournal.com]

For my reference:

Ten common circuits for DIY stuff (http://www.diylive.net/index.php/2005/12/19/ten-most-needed-circuits-for-the-diyer/)

[twi5t.livejournal.com]

Things to make and do: http://www.emanator.demon.co.uk/bigclive/makendo.htm

[7leaguebootdisk.livejournal.com]

I have one of those, also a small one. Dim, but handy, no breakable bulb, no batteries for my 2 & 4 year olds to run down. If I was paying for it, I'd rather get a eternaLight (http://www.techass.com/el/el1.php), probaly one of the ones with the glow or pulse mode (glows dimly or pulses on every few seconds when otherwise off, you have a year or two of run time in that mode, dang handy for finding it in the dark).

[7leaguebootdisk.livejournal.com]

that would be the http://www.techass.com/el/elxray/xray.php

[ewtikins.livejournal.com]

Thanks for the reference. I'm really looking to make things rather than buy them, at this point; I have various useful flashlights already (bicycle lights are usually quite good for brightness, battery life and watertightness).

[7leaguebootdisk.livejournal.com]

With the $25 light you linked to, I wanted to point out a cool flashlight. Now if they redid the components on that light (the one you linked too), it would be half the size (really, the wasted space in it is amazing), and frankly, make it a 3 led light, probably with a digital controller, and make the small one even smaller, I'd really want one.

The lens buys you very litle, turn the circut board sidways, and have the body closely fit the coil and ends of the charging system, now you have a light that is dramatically smaller, with no loss of functionality.

[compilerbitch.livejournal.com]

Get yourself a copy of The Art of Electronics, Horowitz & Hill.

Really.

[uon.livejournal.com]

I'd be happy to lend you a breadboard if you still need one.

[ewtikins.livejournal.com]

That would be great, thanks.

Where are you working these days? Would meeting for lunch at some point suit you?

[uon.livejournal.com]

I'm working at UCL (in Bloomsbury) until the 6th January; I ought to be free for the week after that before starting elsewhere. Lunch any time in the New Year sounds good!

[martling.livejournal.com]

So, some good things to cover might be:

- Using LEDs (they're diodes, and we started covering diodes already; these ones just emit light).

- Turning LEDs or other things on and off in interesting or meaningful patterns (we turn things on and off with transistors, and the patterns come from logic - we covered a couple of gates, the rest is just combinations).

- Charging batteries (how you do this depends on the type of batteries involved, but some are easy).

I'll try and put together a bit of a lesson on the first two by email. The third, I'll need to do some reading on myself. :-)