Electronics on Dave Nelson

Surface Mount Soldering Kits

Wed, 03 Feb 2021 22:26:13 +0000

Assemble and ready to go

In my previous post I wrote about the QRP-Labs QCX-mini amateur radio kit which only has through-the-hole components to be soldered by the enthusiast but had problems with some of the surface mounted op-amps and my desire to learn how to remove those surface mounted devices (SMD) and install new ones. To learn how to do that I bought a handful of kits to practice on.

QRP Labs QCX-mini

Mon, 01 Feb 2021 22:59:08 +0000

Assembled QRP-Labs QCX-mini with dummy load and replacement op-amps.

The QCX-mini is a continuous wave (CW), think Morse Code, ham radio kit that transmits and receives on one band only at around 5 watts. I had been waiting for the release of the QCX-mini kits for a while and was able to order one as soon as it was released. I also bought the aluminum case and the 50-ohm dummy load.

Shack Power

Tue, 01 Dec 2020 23:00:10 +0000

Top of the Powerwerx MEGAbox

We have been having some power outages in our neighborhood recently so my plans for a portable power station have been moved up. I have done a lot of research and decided to spend the money now instead of spending more time trying to find something cheaper.

Battery

The battery I have chosen is a Bioenno Power Lithium Iron Phosphate 12V, 40Ah LFP Battery (PVC, BLF-1240A) and here is why:

Kindle Paperwhite

Tue, 17 Nov 2020 01:00:49 +0000

![amazon kindle paperwhite book reader](https://images-na.ssl-images-amazon.com/images/I/61eAq6gg-XL._AC_SL300_.jpg?ssl=1" style=“float:right;margin:0 0 15px 15px)

While studying for the Amateur Radio license exams I decided I wanted a new Kindle to read them on. Looking at the different versions of Kindle’s available I chose the Paperwhite for its price, size, backlighting, and water resistance. We have an original Kindle Keyboard and it still works, but it is larger and heavier than the Paperwhite, is not water resistant, does not have a backlight, does not have a touchscreen, and is awkward to hold. I was hesitant to buy a new Kindle as I had not been using the old one very often until I started studying for the license exams which is what got me to use the old one a lot.

Mechanical Keyboard Macro Pad

Sun, 29 Mar 2020 13:08:55 +0000

Handwired 2×5 Macro Pad with 3D-Printed caseWhile on lockdown for COVID-19 I decided it was the perfect time to build my first hand-wired mechanical keyboard and that starting small was the right way to begin. After much searching and thinking I chose a [2×5 case](https://www.thingiverse.com/thing:2509293 noreferrer) that I found on ThingiVerse by [Jacob Jaeggli (jakebot)](https://www.thingiverse.com/jakebot/about noreferrer) and with [Kailh BOX Heavy Burnt Orange Switches](https://cdn.shopify.com/s/files/1/3099/8088/files/BOX_Burnt_Orange.pdf?5816470357010718290 noreferrer) and a quick trip to Microcenter for a Teensy 2.0 Arduino board and diodes I got started.

Mechanical Keyboard Switch Choices

Tue, 27 Mar 2018 19:30:31 +0000

There are an overwhelming number of different switches for mechanical keyboards available. Linear, tactile, clicky, buckling spring, vintage, and each in a wide range of spring weights and crispness.

From Novel Keys I ordered a 25 slot switch tester with a selection of Cherry MX, MOD, Gateron, and Zealio switches along with a Kailh Sample Pack of another 27 switches. Then from Thingiverse I printed out a PLANCK keyboard frame with room for 48 switches. Now I have a switch tester that I can take around and really get a feel for a wide range of the current switches available.

Mechanical Keyboards

Tue, 27 Feb 2018 13:33:38 +0000

If you read my review of the 2016 MacBook Pro you know how much I dislike the keyboard on it. Along with that I have been reading Norman Chan on Tested.com, co-workers, gaming sites, and “computer experts” talking mechanical keyboards and how wonderful they are, my interest was piqued.

My goal for a keyboard is for it to be comfortable and to give a reliable amount of feedback for my not-so-fast touch typing. I don’t need it for “gaming” or a crazy amount of n-key rollover. Just something solid, reliable, and comfortable. I would have loved to build a keyboard kit with all the soldering and programming that entails, but I have other things I would rather be doing. So I spent months shopping and comparing every mechanical keyboard I could lay my hands on.

OctoPrint and the Prusa i3 MK2S

Tue, 11 Jul 2017 11:30:17 +0000

I ran the Prusa i3 Mk2S for a couple of weeks by copying files to the SD card and then printing from there.I could have also printed directly from a computer plugged into the printer, but that computer would need to stay connected and powered on while printing. Either one of those solutions work well enough, but I really wanted to be able to print from multiple computers while not dedicating a laptop or desktop to printing, and most of all I wanted to be able to monitor the printer remotely with video.

Prusa i3 MK2S 3D Printer

Mon, 03 Jul 2017 11:00:41 +0000

![Assembled Prusa i3 MK2S](https://shop.prusa3d.com/312-large_default/original-prusa-i3-mk2-kit.jpg" style=")

I spent a lot of time and energy researching 3D printers before finally buying one, and even then I am not real happy with the first one I bought, but that will be another post. This one is about the second printer I bought and love, the Prusa i3 MK2S Kit.

The Prusa i3 MK2 is a very popular and highly rated printer, Make Magazine gave it their Outstanding Open Source, Best Value, and Best Overall awards in 2017. Thomas Sanladerer says “The Original Josef Prusa i3 MK2: It doesn’t get any better than this!”

Team Black Sheep Vendetta Tips

Sat, 09 Jul 2016 14:00:44 +0000

I have gone all in with the TBS Vendetta, I have put the ZMRs and the Shendrones Krieger away. I am now exclusively flying a pair of Vendettas that I have named McCoy and Hatfield.

The Vendetta is not perfect and it is not indestructible. It is a multirotor for experienced hobbyists and it is not for beginners. I would only recommend it to someone who has built more than 2 difference quads of their own and gone through the experience of tuning, flying, crashing, and breaking.

ZMR250 Multirotor Frame

Tue, 03 Nov 2015 15:00:57 +0000

ZMR250 Frame

My first 250 size quadcopter frame was a ZMR250 which I have been told is a clone of a Blackout 250. The Blackout costs $150 from GetFPV while the ZMR is available for as low as $20 from various sources. I got my first one from Banggood in May 2015, it required some drilling to get the 2204 motors to fit the arms and the SMA VTx to fit through the top plate, but I was pretty happy with it overall.

ImmersionRC Vortex Pro-Tunes

Tue, 27 Oct 2015 20:00:20 +0000

Vortex 285 – FPV Race Quad
The Vortex comes with 10 “Pro-Tunes” that were developed by sponsored pilots before its release. I did a bunch of Googling after buying the Vortex to try and find more details about these varoius tunes and found nothing more than a short video from UmmaGawd about the Vortex.

So here are all the tunes as of October 2015. I hope they add some new ones soon that are specific to newer motor and prop combinations, especially DAL props.

Immersion RC Vortex First Flights

Tue, 20 Oct 2015 20:00:04 +0000

Vortex 285 – FPV Race Quad
I have seen a handful of people flying Vortexes around the Atlanta area and after rebuilding my ZMRs like 5 times I decided to give the Immersion Vortex a try.

I bought it from Atlanta Hobby along with both the Carbon Fiber Crash Kit and the Plastic Crash Kit. I also got a cable to allow me to easily connect a Spektrum Satellite receiver without having to make a cable of my own.

Getting into RC Helicopters

Tue, 14 Jul 2015 20:00:13 +0000

Last year I saw a video of a guy flying a remote control helicopter upside down… A HELICOPTER… UPSIDE DOWN!

I watched that video and others like it over and over. So I started saving my money and researching what kind of equipment I needed to learn how to do that myself. I started off with a cheap toy helicopter, then moved to a more expensive one that was much more powerful but still a toy and then finally with a hobby-grade collective pitch heli.

Amateur Radio Technician Exam

Tue, 26 May 2015 21:00:27 +0000

As you may have read in previous posts I studied and took the Amateur Radio Technician Exam recently, it was a great experience.

I bought a study guide and read it on a Kindle and the iOS Kindle app then took around 100 practice exams using an iOS app. All told I spent about 5 days studying after work and at lunch.

Using the National Association for Amateur Radio’s website I was able to find a local test which was on a Saturday morning at a local church around the corner from my house.

Amateur Radio Exam Prep: Technician by Patrick J Maloney LLC

Tue, 19 May 2015 21:00:56 +0000

Amateur Radio Exam Prep: Technician is an iOS app for iPhone and iPad to help you pass the ham radio technician exam. I am taking the exam to get my license so that I can legally use 5.8GHz video transmitters for first-person view remote control flying.

This app with a good study guide should easily get you through the technician exam. I read a study guide and took about 100 practice exams before taking the test and only missed 2 questions.

Learn Raspberry Pi with Linux by Peter Membrey and David Hows

Tue, 10 Feb 2015 14:00:22 +0000

This is the Raspberry Pi book I have been looking for. Instead of trying to push some advanced scripting language or Linux distribution, this book shows you how to use the most widely used distribution, Raspbian, and good old Bash scripts to do useful things with a Raspberry Pi.

Now 3 years old the lessons in Learn Raspberry Pi still hold up. Raspbian has been through some major updates and the new Model A+ and B+ computers have added to the Pi’s capabilities, but the Linux/Unix commands, SSH and VNC techniques, network information, Web Server installation (LAMP), and a decent chapter covering compiling XMBC on your Pi.

BeagleBone Black WiFi Adapter (WNA1100)

Fri, 02 May 2014 12:30:24 +0000

Boris, the BeagleBoard Logo MascotI initially bought an Edimax EW-7811Un Dongle for use with my BeagleBone Black (BBB), but after a lof of fiddling and frustration I gave up on it. Turns out that I may have been using the wrong setting in the interfaces file, but after some research I found many instances of people complaining about the Edimax dongles in general, so I started looking for solutions that others were having good luck with.

Unable to Connect to BeagleBone Black via Ethernet

Fri, 25 Apr 2014 11:00:09 +0000

Unable to Connect to BeagleBone Black via Ethernet

Everything works fine when the BeagleBone Black is connected to a computer via USB but when connected to the network via Ethernet it does not work. I ran into this issue when I first started using my BeagleBone Black out-of-the-box and again when I updated the OS to Debian.

Here is the solution:

Connect the BBB to your computer via USB and give it time to boot
In a web browser open the Cloud9 IDE by going to https://192.168.7.2:3000/. You may be prompted to choose some settings, I like the defaults.
Create a new file, paste in the script below, and run it

var fs = require("fs");
var destroyed_key_file = "/etc/dropbear/dropbear_rsa_host_key";

fs.readFile(destroyed_key_file, function (err, data) {

  if (err) throw err;
  
  if( data===null || data.length===0 )
  {
    console.log("we have a corrupted host key file... try do delete it");
    fs.unlink(destroyed_key_file, function (err) {
    if (err) throw err;
        console.log("successfully deleted " + destroyed_key_file);
        console.log("you should now reboot your beaglebone.");
        console.log("the /etc/init.d/dropbear script will create a new rsa host key file for you.");
        console.log("after the reboot you should be able to login over ssh");
    });
  } else {
      console.log("it seems that you have another problem, sorry");
  }
});

Now shutdown, I like to sudo shutdown -hP now, the USR lights will all go out when it is shut down
Now you can unplug the BBB from USB and plug in an Ethernet cable and power adapter. You should now be able to access the BBB from anywhere on your network using https://beaglebone.local or ssh beaglebone.log.

Thanks to httpss://groups.google.com/forum/?fromgroups=#!msg/beagleboard/Ya2qE4repSY/u4lvOjF66JEJ

Remote Host Identification Has Changed!

Fri, 18 Apr 2014 11:00:27 +0000

After updating the operating system to Debian and plugging in your BeagleBone Black via USB you may receive the error message:
WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!

This is normal as the RSA key has changed when you updated the OS.

The easiest way to fix it is to run ssh-keygen -R then try connecting again.

When connected via USB
ssh-keygen -R 192.168.7.2
ssh debian@192.168.7.2

When connected via Ethernet
ssh-keygen -R beaglebone.local
ssh debian@beaglebone.local

Setting up Debian on a BeagleBone Black

Fri, 11 Apr 2014 11:00:30 +0000

This post is about installing Debian (BeagleBone Black – 2GB eMMC) 2014-03-27 and Flashing the eMMC using a Mac running OSX 10.9 Mavericks.

I decided to get a head start on using Debian with the BBB which is soon to tbe the default OS installed on them.

These are the steps I used today to get up and running:

Download image from http://beagleboard.org/latest-images
– BBB-eMMC-flasher-debian-7.4-2014-03-27-2gb.img.xz
Use Unarchiver to extract disk image
– BBB-eMMC-flasher-debian-7.4-2014-03-27-2gb.img
Download PiFiller to copy the disk image to the SD card
– https://ivanx.com/raspberrypi/
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Run PiFiller and follow the directions
- Choose the disk image
- Insert the SD card
- Verify that PiFiller has found the correct device
- Some more verifying, click OK a couple of times
- Now wait awhile, it took about 20 minutes on my MacBook Pro Holy Cow! The dialog box opening and closing gets really annoying to watch!
- All set when you get the “Your SD card is ready” message
Eject the SD from the Mac OS then remove it from the computer
With the BBB unplugged, no network, USB, video, power cables, insert the SD card into the BBB
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Get ready: When plugging in the BBB you will need to hold down the Boot button until all 4 USR lights turn on
– While holding down the Boot button insert a 5V 2A power supply, release the Boot button when all 4 USR lights turn on
Now the USR buttons should start blinking in a seemingly random pattern, this should go on for 20 to 60 minutes depending on the OS and SD card
When the USR lights all light-up again the eMMC has been flashed with Debian
Remove the power adapter
Remove the SD card

BeagleBone Black Microcontroller

Fri, 04 Apr 2014 11:00:34 +0000

I recently bought a BeagleBone Black (BBB) and am having a great time with it.

From the website beaglebord.org:

BeagleBone Black is a $45 MSRP community-supported development platform for developers and hobbyists. Boot Linux in under 10 seconds and get started on development in less than 5 minutes with just a single USB cable.

What I Bought

I bought my BBB from Makershed as a part of a kit which included the book Getting Started with BeagleBone by Matt Richardson and a handful of electronic components. The kit is not bad, but I feel like it is overpriced, especially for someone who has a lot of components already.