Adafruit arcade buttons

For my alarm clock project I bought two translucent arcade buttons from Adafruit. Here's some things that I observed after I got them, especially on placing an LED inside. I couldn't really find any other examples or information about working with these, except this music keyboard project that Adafruit posted on their blog. They drilled LED-sized holes in the bottom and hot glued the LEDs in, but I didn't want to drill a hole.

   

Relative size. They look a little smaller here, but they are about medium size.

Side view

Bottom view

The tabs on the side hold the button in the hole that you drill for it. They compress and push out and there are multiple "steps" at the top depending on the thickness of the mounting material.

The inside. The top cover is pretty easily taken off by pushing in the snaps/tabs. The white part extends down to press on the switch on the bottom. It has a large white top surface, which makes the tops of the buttons look whitish and not see-though.

The white top part attached with no top cover.

Inside. There's a pretty good amount of room to mount lights, a little bit of circuitry, etc.

Here's a side view so you can see how much room there is. It's translucent, so you can see the center white post through the button and see how much room there is on the side of it.

The button, which is released by tabs in a similar way to the button top.

Putting an LED in. There is plenty enough room. I'm using an LED with long leads that can be bent around and through the side holes. It happened to be a tall, smooth LED with no rim on the bottom. It's green, sorry that it blends in with the blue switch.

I would suggest putting two in on each side of the switch, because the light gets diffused some by the white top, so it partially looks like a dot of color on one side. Putting two on each side would make it much better. The light goes through the button alright (like fiber optics), but again it would be better looking with two LEDs.

Side view of an undepressed button. The top is slightly convex, which is a little hard to see on camera, but easier in person. It's hard to feel, the top feels pretty flat. The datasheet also shows that it is convex. 

Depressed button.

Nova: Hunting the Hidden Dimention

www.pbs.org/wgbh/nova/fractals/ - This is Nova's website for their movie/show Hunting the Hidden Dimention, which is about fractals. (Fractals are mathematical objects that basically repeat within themselves, e.x. in a fractal image, you see the same or similar designs as you "zoom in" or get smaller/simpler.) Nova has very good explanations of things, with slideshows and interactive applications.

Make: Electronics book

This book has been published by O’Reiley Media, which also publishes Make: Magazine, a great DIY, “maker,” and hobby magazine. Make: Electronics is meant to be a new kind of introduction to learning electronics as a hobbyist. It teaches with “learning by discovery” and has the reader experiment and make mistakes, instead of just learning theory.  I agree with this method for learning and have experienced how this makes the book very good. It explains difficult concepts well and its atmosphere is very friendly.

Multiple people have said Make: Electronics is the new, main, go-to book for an introduction to electronics. Many people used to say this of Forrest M. Mimm’s An Introduction to Electronics. I own his book and did not find it very good. I found it quite advanced, abstract, and confusing. Even when I came back to it after a while I still couldn’t grasp some important concepts. I would strongly recommend Make: Electronics instead.

Note that if you want to get through Make: Electronics, you need to buy many tools and components. There are two kits you can buy from the Maker Shop that cover the parts for the first and second half of the book. This can be very helpful, but both of these kits cost about $100 each.

How Round Is Your Circle? review

Here is my previous post on this book and its website, howround.com

The subtitle for this book is Where Mathematics and Engineering Meet. This is a good summary of the book, as it looks at interesting ideas, concepts, situations, and problems in both fields, but relating both to the current topic. The major topics are on making accurately straight lines and round circles. Other ideas discussed are constant width solids (not always spheres), leaning stacks of dominoes, mechanical linkages, drilling square holes, and other irregular shapes, solids, and methods for doing physical, mechanical things.

I think the authors hit the nail on the head for a good topic to right on. The book appears to be interesting and written very well, and I plan to enjoy it a lot.

How Cars Work by Tom Newton

How Cars Work by Tom Newton

I got this automotive book a while ago and I greatly enjoy looking back into it.
This is a first rate book that has the perfect amount of information. It's easy to understand and talks about all the important parts in a car. It's sort of meant for the very basics in learning mechanics, but is excellent for the casual person who would just like to know about these things. I highly recommend it.

"Concise Electronics" learning resource

Originally found on makezine.com: http://blog.makezine.com/archive/2010/10/concise_electronics_for_geeks.html

http://lcamtuf.coredump.cx/electronics/
Concise Electronics, by Michal Zalewski, is an online learning resource for studying and learning about electronics. It looks very good and interesting and aims to be what other sites have not. It's simply a long webpage organized similar to a textbook or a how-to. Aimed for hobbyists or enthusiasts who may just want to know how stuff works,  it looks very in depth at times, but this allows you to truly understand what's going on.

Here's the author's description:

There are quite a few primers on electronics on the Internet; sadly, almost all of the top hits resort to gross oversimplifications (e.g., hydraulic analogies), or convenient omission, when covering subtle but incredibly important topics such as the real-world behavior of semiconductors. There are some exceptions, to be sure - but they tend to suffer from another malady: regressions into mundane, academic rigor, complete with differential equations and complex number algebra in transient analysis - a trait that is highly unlikely to be accessible, or even useful, to hobbyists.

The goal of this guide is to bridge this gap; it should give you an anatomically correct insight into the underlying physical phenomena needed to accurately understand the behavior of semiconductors, capacitors, or inductors - but should be far more readable and way shorter than a typical academic textbook, and mostly stripped of useless trivia and other fluff. The target audience is people who want to meaningfully tinker with more complex electronic circuits, or perhaps understand how computers really work - but for whom getting there is not meant to be a full-time job.

Zero: The Biography of a Dangerous Idea by Charles Seife

http://www.amazon.com/Zero-Biography-Dangerous-Charles-Seife/dp/0140296476

I recently read Zero: The Biography of a Dangerous Idea by Charles Seife. It's an interesting book that discusses the importance of zero and describes its history. You might have heard that back when counting and number systems were just being started, people didn't think of a number/digit that had the value of nothing. Somebody must have thought of it some time, yes, but it was much more complicated than that. Zero turns out to have been a very controversial concept that applies to historic worldviews and modern applications.

If you're in to math, I'd certainly suggest this book. But I agree with an Amazon.com reviewer that the author is a little too flowery and poetic sometimes.