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?
Pi Plate Stacking
Category: Electronics
Fresh Pi in the mail
Newly arrived in the mail today! I received my first Raspberry Pi as I feel immediate guilt over the Tindie PIC boards I have waiting to be populated and explored. I look forward to loading up the OS and finding some to plug this into for video… my TV isn’t very practical for hacking away at hardware. I appreciated the low cost of the shipping from Adafruit but the items shipped in a soft pack and the box got somewhat crushed as view below. Maybe it’s a little retentive but I wish they would have shipped it in a small box. Nothing was functionally damaged of course so I can’t complain to much. I’ll spend the evening putting together the LCD interface it, Proto Plate, a little level converter for my BMP085 breakout board (Sparkfun) and The Pi Cobbler kit.
Product links:
Proto Pi: http://adafru.it/801 4 bit level conv: http://adafru.it/757 cobbler kit: http://adafru.it/914 16×2 LCD display: http://adafru.it/181
OP Amps
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!
Talos the Sumo Roomba
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.
Workshop check…
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!
Homebrew TDR
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.