Charles Ihler

So I need to find long leaded 26 pin headers if I’m going to stack Pi plates.. I’ve found some over seas but I don’t want to pay shipping and I was hoping for a state-side supplier, anyone buying these out of the US?

I remember my first electronics book was a project book with assorted transistor and tube circuits. I steered clear of OP Amps through my younger twenties even.

I recommend some day you’re sitting around at your bench wondering what to make or fix next… day some time to refresh your OP Amp skills.. I could never match W2AEW’s Op Amp video, a great refresher for those who forgot how much we forgot and the newbie!

My sumo roomba is running around but has a lot of tweaking yet to be completed.

To do list:

Fix the IR sensor interface, it’s flaky.

Add bumper sensors & code to turn into them.

I probably put too much work into measurements and sensors monitoring. I have a tablet that I can monitor most items in case I want to record anything. It’s bluetooth (the only use for the bluetooth module). You’ll note it runs on two PICs, one for drive and offense/defense, the other for monitoring, communication, and subsystem work. The battery was bad so I dropped a 12V 1.2AH SLA into the case.. not the best fix but it works fine.

We don’t have “workbenches” any more right? That got boring? Mine is a little pathetic right now. We moved from San Diego out of a tiny 900sq ft apartment with three of us, to this house. So with all this new space I’ve planned on a late May  visit to my house in South Dakota which still has my workbench and much of my test equipment. I’ll post a new photo in a few months, you still won’t see much test equipment, I can’t stand being crowded with test equipment; I like plenty of project/arm room. The bench I’m bringing back was a lucky score; I bought it off an electronics factory (that got out-sourced to China)… Not to mention boxes and boxes and boxes of books. I love looking at workshop photos, please comment with yours!

One of my favorite vloggers is w2aew. A recent posting has got me thinking TDR…. supersized. I was planning on playing around with a compass/barometic pressure sensor with the Raspberry Pi but that may wait.. (or perhaps I should pick up a cheapo model A). I don’t use a lot of coax these days but a TDR for CAT5 might be handy. If you watch this video I imagine you can fill in the blanks and see how I believe with an A2D converter and a stable parts (read: frequency) you could have yourself a real nice basic TDR.

5 EA 74AC14 ‘s are $3 and some change right now on eBay. I had some eBay bucks ready to expire so I ended up getting mine for “free”.

I tried the circuit out with a 74LS14 which is obviously turtle powered compared to the ‘AC14.. I could still determine the approximate length of my CAT5 even with the circuit on a breadboard. If you make an attempt the value’s used in the video will not work. If you need a little help ( http://www.electronics-tutorials.ws/waveforms/generators.html ) If you’re going the same route don’t forget CAT5e’s impedance is roughly 100ohms so make the necessary changes in your parallel resistors.

I was reading an elektor article and ran across the “BaroStick” Article. ( http://www.elektor.com/magazines/2013/may/barostick.2457910.lynkx ) — I have a Raspberry Pi on my birthday wishlist which I’m fairly certain I provided adequate hinting that it was the “to buy” present. It was the CanaKit that comes with all the typical goodies. I’ve been a long time user of the Microchip PIC chips and I’ll continue using them in designed but I felt that I need to break out of my VB.NET and assembler shell. Python actually looks worthy enough to tie up some neural connections; in the process of reading Simon Monk’s “Programming The Raspberry Pi” . The very same elektor also has an interesting article on BASIC to Python (May 2013 pg 26). Those of you who know me know I’m not a huge fan of C. You can keep your C and just chalk me up to a lost cause if you desire.. C is just not for me. I’ve done all the handy C introductions and hello worlds and manipulated it where I HAD to…but I’ll stick to assembler and BASIC thank you. I’ve also dabbled in plenty of PERL and COBAL and was formally educated with Pascal. While we’re talking about ridiculous aversions; I also have a huge, totally un-based, beef with Arduino… Like Apple vs. Microsoft beef. So you won’t catch me with an Uno unless I needed it to test the dielectric properties of FR4.

Okay stay with me… almost there.

Because of that distaste for all things Arduino; I never visit Adafruit ( http://adafruit.com ) unless I want to be reminded how perfectly lovely female EE’s can be. That being said I had purchased a BMP085 from my favorite website to visit when I’m feeling project-idea-block… Sparkfun last March. ( breakout board found at: https://www.sparkfun.com/products/11282 )  I love their breakout boards.. a second stop would be http://www.tindie if you’ve been under a rock and find yourself trying to consider some “fun” projects to take on. With this BMP085 breakout board I have on my “to-do” list to build a altimeter for hiking. Is it heavier, yep.. going to use more power? Yep… look as attractive as that Suunto $500 watch? No where near.. but it’ll come off my bench. Turns out in my web expeditions to save myself some coding out dearest Limor has taken all of the work out of it.. ( http://learn.adafruit.com/using-the-bmp085-with-raspberry-pi/overview )  with a small fix: ( http://forums.adafruit.com/viewtopic.php?f=19&t=38293#p191390 ). Will I be visit adafruit more often? Maybe so…

I’ll report back on this project once my birthday rolls around.