I like that use of an annular bit to create island pads. I imagine doing things such as gluing down a VCC bus strip, or I suppose you could use a file or dremel to create a bus along one edge, or through the middle.

I could sure use a paid vacation.

But for electronics, the #1 thing on my Xmas list would be an oscilloscope.

Hi Folks.

I'm sitting here reading 'Circuit Building for Dummies', and came across the 'Dead Bug' and 'Manhattan' methods for building prototype circuits. Thought I'd mention them, for the benefit of those who hadn't know about them. I found some examples doing a Google image search, some of which combine the Manhattan and Dead Bug methods.

Some pictures: http://people.wallawalla.edu/~ralph.stirling/Engr/PROTOTYP.HTM
GIS dead bug
http://www.dummies.com/how-to/content/building-a-circuit-deadbug-style.html

That should get you started, if you're interested.

Doesn't have to be ugly either.

Does she come in a DIP package?

So tempting ... so tempting ... 

Focalist, perhaps something resembling a Rosie the Riveter motif? Well, Wired did that for Limor, and it worked for them.

Uh, I'm not much for calendars. Sorry.

I think I would punt and either:
 * determine it empirically by driving the motor n steps and measuring the angle before and after, or
 * use servos instead of stepper motors. servos are already designed to go to angle X and stay there.

OTOH, I don't see a huge math problem here. You just want to determine degrees of rotation?

So, imagine a 180 step stepper motor. So each step is 2 degrees. If you want 0.5 degree per step, then you'll need a 1:4 drive ratio.

Here are some stepper motors. Note these are all 1.8 degree steps. Or, you could by a 20-step per turn motor, then each step is 360/20 degrees -- for that, 1:20 drive ratio would get you 1 degree per step.

http://www.hansen-motor.com/step-motor-19.php -- 7.5 and 15 degree steppers. You can also get steppers with attached reduction gearboxes.

This is just multiplication and division, to determine how many degrees you get, based on your drive ratio.

You're welcome. Glad to find something I could speak to.

BTW, I can think of cases where I might find it reasonable to build a battery charging circuit. A remote device, where batteries are used as an energy store, and charged with solar. Even there, I'd look for an IC purpose-built for the battery type. But the OP didn't indicate any such installation.

So for fun I followed that e-bay link. The seller is advertising those batteries as 'safe and environmentally friendly'. Hah! Well, the protected batteries are pretty safe, but lithium salts aren't 'friendly' at all, AFAIK. Just FYI, I've had the switch / regulator / protection circuit on 2 e-cigs fail in the dead-short mode. Didn't smell as bad as burning plastic, and I caught it before it did any damage.

Agreed, but again, these are Li-Ion batteries. Li-Ion batteries are MUCH safer than Li-Po batteries, otherwise they wouldn't be in every mobile phone. I've never heard of a mobile phone bursting into flames...have you?

No, the basic Li-Ion chemistry is not much safer. There have been cases of phones overheating, and also laptop batteries. I thought the HP problems were well known. Sony too, IIRC. And, in the world of electronic cigarettes, the problem with Li-Ion batteries is well known too. Battery University is a great resource. I suggest people read there. Candlepower Forums as well.

There are some Li-Ion family battery chemistries which are much safer. Lithium-Manganese, and Lithium-Ferro-Phosphate, for example.

The Li-Poly designation has nothing to do with battery chemistry.

https://en.wikipedia.org/wiki/Li-poly

The primary difference is that the lithium-salt electrolyte is not held in an organic solvent but in a solid polymer composite such as polyethylene oxide or polyacrylonitrile.

The wikipedia article further mentions that the positive electrode is either Lithium Cobalt or Lithium Manganese. Of these 2, the Cobalt salt is the common Li-Ion material, and so any Li-Poly battery using such chemistry will not be inherently more or less safe than other common Li-Ion cells. There's a reason why you can find 'protected' Li-Ion batteries. The manufacturers of these (AW, Tenergy, Ultrafire, etc.) add the protection circuit to the cell. But these protection circuits can fail too. In a mobile phone, the battery is a Li-Ion, even if it's a Li-Poly  configuration. The overcharge protection circuit is included in the phone's electronics. The protection circuit should also protect against over discharge, both in terms of excessive discharge, and overcurrent.

I don't use common Li-Ion cells at all (except in my phone, where I have no choice, and in fact I don't know specifically what chemistry it uses); I use LiMn, and will probably be using LiFePo in the future. I also use a Pila IBC charger. Lots of people (this is from the e-cig forums, and flashlight forums) don't trust the cheaper chargers to shut off. (Similar to a couple recent threads we've had here on el-cheapo DC-DC converters.)

Also, as I understand it, lithium fires can't be extinguished with water. So buy a good charger. If you want to be really, paranoid, there are Li-Ion charging bags.
http://forcedfuel50.fatcow.com/sitebuildercontent/sitebuilderpictures/.pond/LIPOBAG.jpg.w560h446.jpg
(Found that at Super-T manufacturing, who is targeted to the e-cigarette market.)

anyone got a better grasp of technical german??

No but if you scroll down the data sheet the bottom half is repeated in English! 

You could've really impressed us all by omitting that, and just posting the English part with a 'here you go!'  ]

pins for same,

http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?freeText=100766&langId=-1&storeId=10001&productId=100766&search_type=jamecoall&catalogId=10001&ddkey=https:OrderItemUpdate

I looked around a bit for a solder-tail version of something like that. You'd think it'd exist. Well, you can certainly solder onto one of those, then insulate it with shrink tubing.

It sounds as if you're looking for some configuration of female SIP connector. Does this look like what you want -- I mean, not specifically, but just the general idea?

http://microcontrollershop.com/product_info.php?products_id=2217

You can get that sort of thing in all sorts of configurations.

I am trying to figure out why there is some hot sauce next to the soldering iron (though thats some good stuff)

Water to wet the tip sponge for the soldering iron? I think my bottle is mayonaisse. 

I just put that there for fun. Nice that someone recognized it for what it is. I do like the idea of having a squeeze bottle for water.

For those in need of enlightenment: http://theoatmeal.com/comics/sriracha

I shall satisfy the "messy desk" requirement.

Nice. I'd have to get stuff out of storage to approach that.

Now we're talking, a bloke could really get some work done there

OK, I'll see your messy bench and raise you an absolute tip of a workshop.

I bow to your superior mess!

I suppose I could post pics of my office desk, and my other work table. That would put to rest any questions about my mental state. 

Fear not. I've had the benchtop in place for a couple weeks, and it took only a few days for it to become completely covered.

I thought there was a newer thread than the one in the old forum, which I could resurrect, but I can't find it, so ...

I finally built a new workbench. My other one is just too cluttered, and trying to do reloading, the odd woodworking project, and electronics, all on a folding conference table is nearly impossible -- particularly for me. The material for this one was all free; I did spend little money on shellac and some corner brackets -- it's mounted to a cleat on the wall on one side, and my desk on the other. I figure it will never be this neat again, so I had to take a picture. Still a few additions to make to it, but I now have a mostly dedicated electronics bench.

http://arduino.cc/forum/index.php/topic,6037.0.html

Yes, the bits are probably on the old-ish and probably need replacing.  However, as I said, I had bought a concrete bit specifically to hang some shelves (project #823 of my undone projects) and I couldn't get it to make a hole with the new bit.  So, I assume I need something with more torque.  I don't know when we bought it, but I think my wife bought it primarily as a power screwdriver.

Concrete can be quite difficult. I don't remember that I've ever drilled into it with a plain old drill. It really takes a rotary hammer (hammerdrill), and even then, I've come across some concrete which was very hard, and gone through multiple bits. If you look at a masonry bit, you see that the end isn't a cutting edge, it's more like a broad v-shaped chisel. The intent of that is to break the concrete (or mortar, or brick). Just spinning it will get you almost nowhere, unless you're drilling into something softer, like plaster, or maybe some brick or mortar. I used to have one of these. That was the shizznit! Works as a regular drill too. There are smaller versions from various makers available. Even cordless.