Introducing the AddOhms TutorialCast

Over the past several months I have been kicking around a new way to teach non-engineers about electronics.  My idea is to use simple language to explain complex engineering subjects.  Each video will be in the range of 3-5 minutes.  While putting together the first couple of topics I started to realize I wanted this to be something to stand on its own.  So I have created a separate webpage, twitter account, and YouTube channel for this TutorialCast called “AddOhms.” Read more

Prototyping quadrotor arm mounts with MakerBot Replicator 2

While practicing the Quadrotor‘s motor mounts on a Shopbot gave me experience in how to register two sides for milling, I didn’t want to invest the time required for the arm mounts.  So I decided to make use of the MakerBot Replicator 2 to print physical samples in PLA.  Time per piece went from about an hour to about 15 minutes.

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HackEDA: Collecting and Sharing reusable pieces of electronic designs

One of the most commonly used phrases when writing software is “reusable code.”   From the Wikipedia article on “Code Reuse”.  Reusable code is:

the use of existing software, or software knowledge, to build new software.

Software coders have been sharing and re-using code since they first start programming.  So why can’t this same idea be applied to hardware design?  Doesn’t it seem silly to redraw the ATmega328 for an Arduino based project or even the really simple linear regulator circuit?  Well, it can thanks to HackEDA you can start using reusable code to save time (and from creating mistakes).

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From Around the Web #1: Cleaning up the drafts folder

These have been sitting in my drafts folder for what seems like forever.  Here are a collection of cool articles I thought engineers might find interesting.  Topics include:

• EETimes:  How to get the best use from step-down voltage regulator
• EDN:  Who cares about EMI?
• 3 Articles on Op Amps

Check below the fold for these articles.

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100kGarages: CNC Router Bits Demystified

Early on in planning the design for the Quadrotor, we knew that eventually some of the metal parts would need to be milled.  Having very little milling experience, other than a couple of basic-use classes at TechShop, I had no milling experience.  When it came time to start buying router bits for the ShopBot and Tormach CNC routers, I didn’t know what kind of bits were necessary.

Understanding End Mills

Greg over at 100kGarages put together a primer titled CNC Router Bits Demystified, which does a great job of explaining the basics of an End Mill, Ball Nose, Downcut, Upcut etc.

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OSX: Fixing the “Green Screen” issue when capturing your desktop (with Quicktime or other)

After spending too much time waiting for effects to render on my new AddOhms Podcast, I decided it was time to upgrade computers.  When I went to capture a quick EAGLE video on my new MacBook Pro with Retina screen, I realized a problem with the Mac’s auto graphics chip switch.  Quicktime recorded only a green Screen.

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