If you’ve been geeking out for a couple decades, chances are you at least saw the Radio Shack ProbeScope at some point in time.

The Radio Shack ProbeScope
The Radio Shack ProbeScope

I bought one back in the late ’90s and found it to be fairly handy for a number of things. Its sampling rate, as I recall, was 4MHz, meaning you could use it to at least detect the presence of RF in a circuit. I also used it to help me debug the code I wrote to emulate serial communications in the microcontroller for my Digital Setting Circles project.

The ProbeScope included a floppy disk with software on it for both DOS and Windows that allowed you to view the waveforms on your PC by connecting the ProbeScope to the PC’s serial port. Alas, the software was written back in the 16-bit days and won’t run on the 64-bit operating systems on most modern PCs. Plus, who has a floppy drive to read that disk anymore? But if you’ve read any of my other blog posts, you know I have a habit of finding ways to revive old but still useful technology that’s long since been left behind.

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After having not touched the bluetooth-serial interface I built for over a year, I pulled it out of the drawer recently and found it to be dead–specifically, the BT2S module. Seeing that a replacement was going to be $17.95 plus shipping, I began looking for alternatives. I selected the BT2S specifically because it worked at +5V voltage levels. There are a number of similar-looking modules on eBay that sell for much less, but they all use +3.3V supply and logic levels (search for HC-06 on eBay and you’ll see what I’m talking about). Could my circuit be converted to run at 3.3V?

It turns out the answer is yes. I was able to modify the circuit to operate at 3.3V by replacing the MAX232 chip with a MAX3232, the 78L05 voltage regulator with a 78L33 3.3V regulator, and the BT2S with one of the HC-06 bluetooth slave modules available from Amazon, eBay, and several other sources. No changes to the circuit board are needed. I’ve added details on the changes to the project page.

One of the things that intrigued me about my new Elecraft KX3 is that it has a built-in serial interface (the ACC1 port). I thought it might be a fun project to see if I could interface it with my Google Nexus 7 Android tablet via bluetooth, reminiscent of my old GOLog project with the Serial Sender. I couldn’t find much in the way of Android apps that would interface to the KX3 in a useful way, but I decided to put together a bluetooth-serial interface and then see if I could write an app of my own that might be handy for, say, SOTA activations and Field Day.

Although I haven’t gotten anywhere yet with writing my own Android app, I did come up with a bluetooth serial interface that works with the KX3. The detailed project description is here. A PC board is available from FAR Circuits, and the project is designed to fit nicely into an enclosure with a built-in 9V battery compartment.

My bluetooth-serial interface
My bluetooth-serial interface

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So, you probably saw the post I put up a day or two ago about having just gotten a Celestron NexStar 6SE telescope. I’ve been having a ball with it so far. My plan last night was to try using my digital camera to take some video of Jupiter and then run it through Registax software to see what came out of it. I followed the instructions posted on this page at Stargazer’s Lounge. I can’t claim to have done anything original here–just followed the cookbook.

My final image of Jupiter, created from video processed by Registax
My final image of Jupiter, created from video processed by Registax

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I’ve never been crazy about my Meade Starfinder 8″ equatorial Newtonian telescope. The optics seem fine, but the mount is heavy, hard to move, and hard to use. Even with my digital setting circles it’s difficult to get the thing pointed exactly where you want it, and a modest breeze can make it almost unusable. Even getting it set up was a chore. So I didn’t really use it much, and I felt bad about that. So, a week ago I decided to buy myself a new telescope, and this time I chose something much more compact–a Celestron NexStar 6SE SCT.

My new Celestron NexStar 6SE on my living room floor just after unboxing
My new Celestron NexStar 6SE on my living room floor just after unboxing

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If you’re an ARRL member, you probably know that their flagship publication, QST, is now available in a digital edition. It’s good to see that the ARRL has followed many other publications down this path. I already receive digital editions of Sky & Telescope and American Rifleman magazines. What these other magazines allow me to do that QST does not, however, is save the digital edition to my computer as a PDF file so I can view it offline. It’s possible to overcome that limitation with a little work, however.

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If you read any of the tech blogs, you know that the Windows 8 Consumer Preview is now available for anyone to try. What holds most people back from trying pre-release versions of Windows is having someplace to install it that won’t trash your existing OS installation. Often times this is done by creating a new partition on a hard disk and installing the preview OS there. Easier, in my mind at least, is to install the new OS in a virtual machine. That’s what I decided to do this morning. I already use virtual machines for other purposes (for example, I have a virtual machine running Windows XP so I can run some older software that’s not compatible with Windows 7). I use VMWare Player, a free product from VMWare.

It took me a few tries to successfully install the Windows 8 preview, so I thought I’d document what worked for me. Here we go:

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I love my HTC Incredible Android phone. I’ve had it for several months now and I continue to find new and cool ways to use it. Last fall, for example, I was looking for a way to connect my laptop to the internet while visiting my parents in rural Minnesota (they don’t have wifi in their home). I discovered PdaNet, an Android app that allows you to use your phone to connect your PC to the internet–for free. Of course, this is the same kind of functionality for which Verizon and other carriers want to charge you $20 a month–waaaay more than I’d pay for it, considering I’d only use the functionality once every few months. So PdaNet was a great solution for me.

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It’s no secret that I’m not really a big fan of Apple. I do own a 3rd-gen iPod, and that it’s a pretty impressive little device. But by and large, I find Apple products overpriced, and the trend towards being closed systems (you will buy from the App Store, and only the App Store) is disturbing. That being said, I do run iTunes on my PC–thankfully, Apple chose not to release it only for their Mac systems. I find iTunes to be fairly bloated but otherwise usable. I have, over time, ripped almost all of my CDs into iTunes, so it’s my primary repository of music.

Last fall I finally replaced my crappy LG Venus cell phone with a way cool HTC Incredible phone running Android. As you would expect, it’s capable of playing pretty-much any type of music file, either with the included player or one of many third-party apps you can find. What it lacked was a straightforward way of getting music onto the phone. Verizon included a CD with some PC software and a synchronization application, but it was clunky and horrible, and it completely ignored the fact that my entire music collection (like those of millions of other people) was stored in iTunes. I needed a better solution.

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