If you haven’t had a chance yet, try checking out Jack Dunigan’s HAMRADIOSAFARI.COM blog. He’s (from his sidebar) the Senior Management Leader of Aidchild Inc., a project which provides homes for children for orphans living with AIDS in Uganda. While that’s important far in excess of anything having to do with ham radio, he is also a dedicated radio amateur, and has taken to blogging his ham radio adventure in Uganda. Building antennas, assembling a Tuna Tin 2, making a PTT switch, and even the adventure of getting licensed and (unfortunately) dealing with malaria have all been subjects.

Put it in your daily list of reading. And Jack, if you are reading this, best wishes to your endeavors, ham radio related and otherwise.

This 40m transceiver only has around 16 parts, and only a single active device: the ubiquitous IRF510 power transistor which you can even get at Radio Shack. Okay, it’s not exactly a complete receiver: they wired it to a PC sound card, and run an SDR application to get receive audio, but still, impressive!

ea3ghs – MOSQUITO Minimalist Transceiver.

The other day I was in HRO and scanning for some reading material for the long weekend. I ran across Brian Cake’s new book, The ARRL Antenna Designer’s Notebook. A brief skim of it showed that it actually covered a couple of interesting antenna types which I had never heard of: the Box Kite Yagi and the Twin C antenna and some brief forays into other topics, including ground planes and small transmitting loops.

About half the book is dedicated to the Box Kite Yagi, which are basically a collection of Yagi antennas which are carefully designed to optimize gain relative to previous state of the art Yagi antennas. For instance, a six element 2m Boxkite has a boom length of approximately 85 inches, and has a gain of approximately 14.6dBi. If I try to make a 144Mhz Yagi using DL6WU’s classic long Yagi design and with similar gain, I end up with a boom 427 inches long (almost five times as long). I frankly am not experienced enough at antenna design to understand the tradeoffs involved here, or whether there (say) the box kite is more sensitive to fabrication errors, but reducing the overall boom length to such a dramatic degree is very interesting. He also has designs for interesting dual band designs, such as a small 6m/2m yagi that has around a 7 foot boom. Very nice, and thought provoking. I’m wondering whether an antenna like this aimed toward the moon rise/set positions would enable me to receive JT65 EME transmissions. Very neat.

I’m also quite interested in the “C-pole” antenna design. It’s a short vertical antenna which has very good low angle takeoff, and requires no radial system. There was an article about them in QST a while back, but a lot more details in the book.

Some of the more thought provoking antenna design notes I’ve seen in a while. I am glad I picked it up.

There has been a lot of work in recent years toward making amateur level UAVs. This one is a tricopter, and is completely open source. They claim that it can fly for “under $100 in parts, not including the airframe”. Sounds like a very cool project. It splits the computational load between an onboard pic that handles rate damping, PWM of the servos, and sensor capture, and a ground station computer which creates an interface and runs the navigation. Nifty.

Vicacopter.

I’ve got the RFSPACE SDR-IQ hooked up as a receiver again, and using it to feed WSPR. There is a ton of loud RTTY signals swamping the 40m band in the vicinity of the WSPR signals, but I’m still getting some signals. Here is the reports thusfar this evening:

Excerpt

Addendum: Picked up CX2ABP in Uraguay:

Addendum: Overnight, I picked up LA3JJ and VK4YEH among others:

Addendum: Overnight, it appears that my monitoring PC decided to download some security updates and reboot. Hence, logging ceased about 3:15AM local time. I just fired it back up, and got 7L4IOU in Japan and VK6POP in Australia.

I subscribe to quite a few mailing lists relating to ham radio. A few months back, I decided to give the QRP-L a whirl. Unlike many lists like the EMRFD list, QRP-L had a fairly high NSR (noise to signal ratio), but hey, it’s a mailing list. It doesn’t take long to skip over stuff that doesn’t interest you. It’s not worth complaining that people spend more time talking about computer viruses and which sound card interface they use than actual interesting bits of homebrewing and QRP operation.

Today, I unsubscribed not just because it was boring, but because it is whining. Not just whining, but members seem to be piling on the idea that if someone doesn’t operate in a particular way that you approve, that they are entitled to maliciously jam your transmissions.

That’s illegal. It’s also first-order dyed-in-the-wool jackassery.

Goodbye QRP-L. It was nice knowing you.

On second thought, maybe it wasn’t that nice.

Roger, G3XBM has a terrific blog and website, and is always tinkering things together that I find interesting and inspiring. This morning, I see that he’s got a small 2 transistor transceiver for 80m that looks like it could be really fun, and constructed from bits you’d probably find in your junkbox. I like the circuit a bit more than the Pixie, since it doesn’t use an LM386, but that does mean that you need a high-impedance earphone because the audio power developed on receive is pretty low. On transmit, it’s basically a simple crystal oscillator, tapped on the collector. I’m a bit hazy on exactly how it operates on receive though. Of course, that means that there is an opportunity for thinking and experimentation with LTSpice. Very nifty. I might have to breadboard this one up myself.

XBM80-2 An Experimental 80m CW Transceiver G3XBM.

Joachim, PA1GSJ has decided to put up a blog for the KnightsQRSS. I recommend all those interested in QRSS operations to go ahead and subscribe, then we’ll have a common place to talk besides the mailing list.

That reminds me, I really do need to get my own site, QRSS.info working again.

KnightsQRSS.