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My 30m QRSS beacon transmitter is working very well. It has been on the air for more than a day now and has been received in Italy, Belgium, Holland and the UK. This is a 50 milliwatt signal being radiated by a magnetic loop antenna in the attic! Isn’t QRP amazing?

On Sunday I assembled the QRSS beacon into a nice case. This is not my favourite constructional task – give me toroids to wind any day! – but I do like the projects I build to look reasonable. The case I used was one I bought for the abortive 2m FM Fredbox project. I even used the SMA chassis socket I bought for that project as the case wasn’t really suitable for a BNC socket and I didn’t have any of the RCA phono chassis sockets I often use for QRP projects in my junk box.

This case has a compartment for a PP3 9V battery. I had toyed with the idea of using a PP3 battery and building in a regulator to reduce the voltage to the required 5V but space was tight and I was concerned that the heat given off by the regulator would affect frequency stability. Also with a current consumption of 70mA at 50mW output a rechargeable PP3 battery with a capacity of 280mAH would last for less than 4 hours between charges.

I observed that it is possible to squeeze 4 x AAA cells into the same space. Rechargeable NiMH AAA cells have a capacity of 1100mAH. Four of them will provide a voltage of 4.8 – 5.2V which will give 15 hours of operation and require no regulation at all. So that is what I will use.

Fitting the project into the box took a bit of time because it was a tight fit in the case. I had to be very careful positioning the antenna socket, switch and external power / charger socket to ensure they didn’t foul any of the components. One of the frustrating things about boxing-up projects is that you can never find a case of exactly the size you want.

As I didn’t have a suitable battery pack I started off powering the transmitter from the computer. I took a redundant USB cable, cut the end off, determined the +5V and GND leads and soldered a DC power connector to them. That got the rig on the air, where it was almost immediately spotted by PA0TAB. The stability of the transmitter is excellent. There is a slight drift down in frequency by 10Hz or so during the first few minutes of operation. After that it appears to be pretty steady. There does not seem to be any need to encase the crystal oscillator in insulating material or use an oven as some QRSS builders have done.

Later on I dug out a charger for a mobile phone which has a USB socket on it and I switched the power over to that so I could keep the QRSS transmitter on overnight after I had shut down the computer. Nobody spotted me overnight, but I will leave it on for a few days to see whether I can be received further afield than Italy. To be received on the other side of the Atlantic would be a great thrill!

Here is a selection of grabs from stations that received my signal in the last 24 hours:

The weekend before last while operating the Pennsylvania QSO Party, I noticed spots on the DX cluster for the “South Dakota Tea Party“.  At first I thought it was a joke, but Googling I found this contest announcement on the ‘zed.  The contest organizer claims that this contest has “an emphasis limited government and there are no rules.”  Extra points are offered for things like having a valid concealed weapons permit, a hunting license, or fishing license.  I’m not sure how this relates to limited government as all of these are issued by government agencies, as are amateur radio licenses.  (Several of the posts in this announcement thread have disappeared; I’m not sure why.)

For those in amateur radio blogademia outside of K/W/N land, the tea party in the United States is a political movement that has sprung up since the current president took office.  The tea party started out as a supposedly independent grassroots movement, but has clearly emerged as a right wing conservative Republican organization funded by commercial interests.  You can see footage of them here and here protesting taxes and healthcare reform.  Google “tea party signs” and make your own judgement.

While it appears this QSO party is the creation of a handful of amateurs and is somewhat an informal thrown-together event, and albeit on that armpit of an amateur radio forum known as QRZ, this is the first time I’m aware of an operating event with a political theme.  As if it wasn’t enough to have non-stop right wing politics in 80 meter roundtables and on amateur radio forums, now we’re luring people into working stations in a somewhat rare state under the semblance of a political movement and agenda.  It’s distasteful and not in the spirit of amateur radio.

Having politically-oriented operating events could open the door to a whole new realm of contests and special event stations, both conservative and liberal oriented that would offend just about everyone.  Can you imagine having operating events such as the Obama Re-election Party or the Sarah Palin QRO Sprint?  How about the National Rifle Association Worked All Free States Award or the QRP Pro-Choice Contest?  And while we’re bringing politics into amateur radio, why not religion?  How about a Mosques On The Air weekend, or a Westboro Baptist Church Koran Burning special events station?  I could go on and on, but I think you get the idea.  We don’t want to start an arms race of political and religious on-the-air events in amateur radio.

This may come as a surprise, but I did participate in the South Dakota tea party event.  I made no contacts, but since there are no rules I awarded myself 10 billion points and I made a clean sweep of all counties in South Dakota.  Such is life without rules.  Perhaps next year I’ll actually get on the air, but make up my own callsign in the spirit of limited government and regulation, and political inanity….

Before I tell you about the weekend and SDR – I want to do a shameless plug. My lovely wife, Julie is very talented in many dimensions. She’s just set up an online shop on ETSY where you can see some of the beautiful craft items that she makes and perhaps buy them too! Do have a look there – with Christmas coming up, you might find a nice gift for someone special.

Anyway. Back to Software Defined Radio. It’s funny how sometimes you can’t escape a particular topic! On Saturday, the latest Practical Wireless dropped through the door. Naturally I checked the VHF column had come out ok (it had, thanks Rob and the team!) and then started to look through the other examples. I was particularly interested in the review of the FlexRadio 1500 QRP SDR transceiver by Phil, G3XBZ.

What a fascinating looking little box that you plug an aerial and a morse key into, connect the USB to your computer and control the rig and all the filtering from within the computer. Phil had obviously had a good time with the rig and had made some nice CW and SSB QSOs with it. Ideal too, I should think for data modes. Very tempting. I don’t need another rig or anything like that. But if I did….

The next ‘nudge’ towards SDR came from an interesting posting via the Southgate club’s blog about the AMSAT-UK FuncubeDongle. This is a dongle, which takes antenna input via an SMA adapter and plugs into your USB port. It forms a VHF/UHF/SHF receiver, obviously aimed at the satellite market which operates between around 64 to 1700MHz. You can use it with any of the current raft of SDR control programs and thus decode all sorts of modes.

Interestingly, there will be two versions of the dongle – a basic one aimed at the educational/schools market – to allow them to listen / decode transmissions from the Funcube satellite and a ‘Pro’ one with a little more flexibility. The feature set of the basic and Pro models isn’t entirely clear at the moment. This looks a brilliant project. Pricing for the ‘Pro’ model looks to be around £100. A 64-1700MHz receiver for £100. That sounds worth keeping an eye on, doesn’t it!

See the FuncubeDongle site here. But before you do, go and see Julie’s ETSY shop and tell her I sent you 🙂

My QRSS beacon is now on the air, running 50mW into my MFJ magnetic loop in the attic. It is showing up very well right now on the grabber of PA0TAB.

I also saw it less strongly on the grabber of I2NDT, but I forgot to grab the image before it faded into QSB.

Reception reports will be most welcome to:

Benoît Mandelbrot (courtesy of Rama via Wikimedia Commons)

It was sad to read late last night that Benoît Mandelbrot had just died.  He was an outstanding mathematician and the individual that coined the term ‘fractal’.   Obituaries can be found at the New York Times and the BBC.

A closer look into a Mandelbrot set. (Courtesy of Dr. Wolfgang Beyer and reproduced from Wikimedia Commons).

Beside the fractal he is perhaps most famous for the Mandlebrot Set (see an image above), which of course has fractal geometry.  As a grad student, in the late ’80s and early ’90s, myself and a few others would run our computers in our spare time to generate Mandlebrot sets and we would zoom in and explore different regions.  This was outside our main research work but these images were so beautiful it was fun to explore the set by mathematically zooming in to different regions. Professionally I still work in nonlinear science and I was sad to hear of the passing of Mandlebrot.  His legacy to our understanding of the natural world and nonlinear science is considerable.  Here is a clip of a BBC documentary that explains some of what he helped us understand.

Here is the man himself talking earlier this year at a TED talk.

If you are wondering if there is a connection to amateur radio.  Well besides a better understanding of our natural world, Mandelbrot’s work gave us fractal antennas.

Fractal antenna (from a patent via Wikimedia Commons)

QRSS reception by ON5SL in Belgium

I received a reception report today via the KnightsQRSS e-mail list.  Pierre, ON5SL, received my QRSS signal last night in Belgium along with the signals from WB3ANQ and W4HBK, as shown above.  My signal is running QRSS3, that is a 3 second dit, and is the bottom trace.

My set-up was the homebrew transmitter putting out 160mW into the homebrew Z-match and an 88′ doublet (again homebrew).  Helping match the short coax feed to the outside of the house to the doublet’s ladderline is an Elecraft BL2 balun.

Thanks goes to Pierre for the reception report.  This is not the first time he has sent reception report, he sent me one in April and also one in March 2009. I am sure I speak for all who run such beacons that we all welcome and appreciate reception reports of our signals.