Piggybacking

Friday night, I switched over to 30m, tuned around a bit and heard W8UM working SP3EPK. W8UM is the ham station of the University of Michigan’s ham radio club and probably about two miles, as the crow flies, from here. W8UM is a great station. They have a 30-ft. tower on the roof of the Electrical Engineering and Computer Science (EECS) Building topped by a SteppIR beam. They’re driving it all with a kW from a restored Heathkit linear amplifier. Needless to say, they have a big signal.

Even so, I was SP3EPK was S5 here, and I reckoned that I could work him as well. Sure enough, when W8UM signed with him, I called him and bagged him. I noted to Les that W8UM was only about 3 km from me, and he had a good laugh at that.

After our short QSO, Steve, K8QKY, who was operating W8UM at the time, called me and we had a nice chat. I joked with him that W8UM warmed up the ionosphere for me, making it easier for my 75W into an inverted vee to work the Polish station. Thanks, Steve!!

Test Your Sound Card

One of the reasons it took me so long to try PSK31 is that I was using an old laptop whose sound card was questionable. I didn’t want to go through the hassle of getting all the cables and software only to find that the sound card wasn’t up to the task.

Well, if you’re in the same boat, here’s a tip from David, G3UNA, via the Elecraft mailing list:

I came across this in Elektor which folk might want to try with their sound cards.

Go the Elektor website and register as a new user. This will allow you to download quite a few articles free, after which you have to pay. Find the June 2007 issue and then the SDR Soundcard Tester article.

You will need to install some software to display the results. The article points to I2PHD but there seem to be several about.

It’s just a 15kHz 555 oscillator with 2 r/c outputs of opposite phase. These are applied to the sound input of your PC, which will then display the results to determine whether the card has the propoer anti-aliasing filters.

It looks fun.

Another Gem from the GlowBug Mailing List

If you’re as old as I am (52), I’m sure you remember the full-page ads for the National Radio Institute. They advertised courses purporting to teach you radio/TV repair. Well, now, NRI’s’ Radio Servicing Methods course is available for download. Unfortunately, it doesn’t say what year this course is from. My guess is that it’s from somewhere in the 1950s.

And if you were wondering whatever happened to NRI, Wikipedia says,

The National Radio Institute was founded by James E. Smith, a high school teacher, in Washington, D.C., in 1914. It was purchased by McGraw-Hill in 1968 and renamed NRI Schools. James E. Smith remained as NRI chairman until his death in 1973. McGraw-Hill announced in 1999 that it would phase out NRI Schools, citing “changes in the marketplace”. They ceased operation on March 31, 2002.

Thanks to Carl, KM1H, for posting this to the Glowbugs Mailing List.

Free Schematic Software for the Mac

As I’ve noted before, I subscribe to a couple dozen ham radio mailing lists. I keep thinking that I’m going to drop my subscription to one or another, but then someone posts a real gem to the list. For example, I was just getting ready to drop my subscription to the GlowBugs mailing list, when Joe, N6DGY posts this:

There is a freeware package called “jschem” available for all platforms (Windows, Mac, Linux/Unix) that is very glowbug friendly.  It’s very simple to add additional symbols as well.

I’ve only played around with this a little, but it seems like a very cool program.

Master’s Thesis Studies Aging of Electrolytic Capacitors

This master’s thesis not only studies the shelf life of electrolytics, but also some methods of reforming the delectric. The introduction describes the paper thusly:

The aluminum electrolytic capacitor is used extensively in the electric utility industry. A factor limiting the storage of spare capacitors is the integrity of the aluminum oxide dielectric, which over time breaks down contributing to a shelf life currently estimated at one nuclear power electric generating station to be approximately five years. This project examined the electrical characteristics of naturally aged capacitors of several different styles to determine if design parameters were still within limits. Additionally, the effectiveness of a technique known as “Reforming” was examined to determine its impact on those characteristics.

Thanks to Mike Mcarty for posting this link to the GlowBugs mailing list.

Do You Experiment? You Need This Notebook

For some reason, I’m on O’Reilly Media’s mailing list, and I get press releases for all their new books. Most of them are computer-related, so I don’t mention them here. This one’s different, however. This is one that hams could certainly use…..Dan

Maker’s Notebook–New from O’Reilly
Help for Getting Your Do-It-Yourself Mojo Working

Sebastopol, CA—Ask tech DIY enthusiasts, backyard scientists, and makers what their ultimate workshop notebook would look like (as the folks over at Make magazine did recently) and you’ll get a truckload of ideas, opinions, and preferences. So the Make & Craft editors and staffers put their heads together. They boiled down all the feedback, crafted a distinctive design, and devised an ideal wokshop notebook for makers of all ilks.

The result? The all-new Maker’s Notebook (O’Reilly Media, $19.99). Created for makers, crafters, backyard scientists, inventors, and engineers–actually anyone with a creative bent–the journal comes with engineering graph paper packed between its sturdy electric blue cover. And in true maker style, this notebook is born/designed to be hacked, inside and out.

Other maker and crafter notebook goodies include:

  • 150 pages of 1/10” engineering graph paper on a 60# Lynx Smooth Opaque recycled paper which can handle everything from mechanical pencils to fountain pens and sharpies.
  • 20 pages of reference material optimized for DIY projects, with everything from instructions on basic circuit testing with a digital multimeter, to how to chose LEDs, to what size needles to use in different sewing projects.
  • All pages are pre-numbered and non-removable. There’s a field on each page for project label, date, and designer and witness signatures. There are also “From Page___” and “To Page____” fields for threading project pages together.
  • Whimsical geekery packed reference pages, including such as variations on Asimov’s Laws of Robotics, the caffeine dosages of various beverages, how to say “Hello, World” in popular programming languages – things that might surprise people and get them talking to each other–for example, “Did you see the Kenny Rogers Rule of Robot Building?” There’s a saying the folks at Make love: “Keep moving, keep asking questions, keep modeling difference.” Now with the Maker’s Notebook you have a nifty journal in which to renders those models. So get to work!

Additional Resources:
For more information about the book, including table of contents, index, author bios, and cover graphic, see: http://www.oreilly.com/catalog/9780596519414

Nature’s CQ

The birds around here can get very noisy. This morning I woke up to a cacophony of bird calls, including robins, cardinals, and chickadees. And there were a couple of other calls I could not identify.

I asked myself, “Why do these birds have to be so noisy at 5:30 in the morning? Then, it occurred to me that these bird calls are their way of calling CQ. Bird calls are their way of advertising their presence and looking for another to contact.

I also think that sometimes they just sing for the fun of it. It’s what they do and enjoy. And why do we do ham radio? Because we enjoy it, of course!