AmateurRadio.com

Sometimes it seems as if half the posts in this blog relate to trouble with computers.

After I got back from the hospital today I thought I would try some WSPR for a change. Paul PC4T had mentioned that conditions on 80m were good. 80 is not a band I often use so I thought I’d try there. But no sooner than I had tried to change band than the software beeped rudely at me. The console window contained an error message: serial_open: Unable to open COM13 – Invalid argument.

COM13 is a virtual serial port splitter on COM3 which I’d created using Eterlogic’s Virtual Serial Port Emulator, VSPE. I’ve used this utility for years to create virtual serial ports so that more than one program can open my radios’ computer control ports at the same time. I’d used one to try out CW Skimmer with KComm before Christmas. As I’d uninstalled Skimmer I removed the virtual serial port. WSPR, which does its rig control through hamlib, then opened COM3 up just fine.

That’s a temporary solution, but I haven’t given up the idea of running other ham software alongside KComm for good. I think there are other serial port splitters out there (there’s com0com which was far too complicated for me to figure out) but VSPE has always worked for me until now. Don’t you just love computers?

Julian Moss, G4ILO, is a regular contributor to AmateurRadio.com and writes from Cumbria, England. Contact him at [email protected].

Last weekend I attended the Houston Vintage Radio Association holiday dinner & picked up a Philco Tropic Model 3012 during the fundraiser auction. I had let a few other radios go without placing a bid and was beginning to think I might go home empty handed when I saw the Philco “on the block”. A few seconds later I was the proud owner of this vintage receiver.

Philco Tropic 3012

Information on this model seems a little scarce, however the style of case was introduced by Philco in 1951 and used in their line of AM/FM receivers for many years after that. This particular example is a transformer-less AC/DC set with a potentially live chassis and the unusual (to me) lineup of 14Q7, 7B7, 14B6, 35A5 & 35Y4 vacuum tubes.

What prompted me to bid on this particular radio was the inclusion of two shortwave bands in addition to the typical AM broadcast band. The dials are marked off in meters which also appealed to the ham radio side of my interests.

After attaching a short length of wire as an antenna I was able to pick up signals across the two SW1 & SW2 bands so I’ll be interested to see what it can receive with a long wire antenna at night.

After a gentle cleaning with dilute mild detergent to remove dirt I rubbed in some beeswax polish to restore the original gloss. Sadly the plastic dial is cracked in the middle but I can look past that given its a little more unusual than the typical All American Five receiver.

Being over fifty years old I wonder what this radio has been used to listen to and what stories it could tell. Perhaps it gave some youngster his or her first taste of ham radio, listening to shortwave stations and AM QSOs until they received the final demand to, “Switch that radio off and GO TO BED!”

Owen Morgan, KF5CZO, is a regular contributor to AmateurRadio.com and writes from Texas, USA. Contact him at [email protected].

who was in the pot of water, that little by little got warmer and warmer until it was boiling.

I was sitting in the shack having a QSO with Greg KD5EW on 15 Meters when I turned around and took a good look at my surroundings. How did it get this bad? How did this part of the basement become such a mess?

Beginning during the weeknights after work, and continuing next weekend, I am determined to clean this space up and make it more functional again.

It will be interesting to see how many things I find that I forgot about and didn’t realize that I have.

73 de Larry W2LJ
QRP – When you care to send the very least!

Larry Makoski, W2LJ, is a regular contributor to AmateurRadio.com and writes from New Jersey, USA. Contact him at [email protected].

This year, Santa was kind enough to bring me a Raspberry Pi computer for Christmas. I’d been aware of them throughout the year, but had become much more interested recently when I started to see some real solid amateur radio applications for the device.

The idea of having a £25 computer which could be tasked with running programs like WSJT or WSPR was very attractive, as well as being a handy machine for web browsing and general internet use (I’m writing this post on the Pi, for example).

Pete 2E0SQL had posted about getting RTL_SDR running on the Pi which was a very useful and interesting. The only issue that I had was with libusb1.0 – because I was compiling it seemed that I needed to install the libusb-1.0.0-dev package. Once I did that, everything worked well.

Initially, I tried the Remote_SDR which certainly worked, although was a little stuttery. What was more interesting to me was the rtl_adsb program, which I was able to use to decode ADSB messages from aircraft and send these across the network to the Windows laptop running ADSBScope. This was done simply by piping the output of rtl_adsb using netcat as follows:

rtl_adsb |netcat -lp portnumber (where the portnumber is where ADSBScope is pointing)

I was impressed and this worked pretty well and the receiver and decoder seemed sensitive – considering the antenna was downstairs and away from a window.

Dave G4FRE had posted about compiling WSPR on his Raspberry Pi which made a great basis for getting WSPR going.

I had to amend my configure statement as follows:

./configure -with-portaudio-include-dir=/usr/include -with-portaudio-lib-dir=/usr/lib/arm-linux-gnueabihf

Finally, when I ran the make install, I got an error which was quite terminal!

(no rule to make target mept162.f needed by WsprMod.w.so. Stop

However, Googling around a little, I found that a number of people had had the same issues compiling the latest release of WSPR, so I downloaded the 2840 version from the repository using the following command:

svn co http://svn.berlios.de/svnroot/repos/wsjt/branches/wspr -r2840

I still needed to use the amended configure statement but this seemed to work ok. The program compiles up and starts and I was able to select a USB sound card. I haven’t yet tried a decode (the Pi is in the lounge and not the shack!) but will aim to do that soon.

Next to compile was WSJT and I used Dave G4FRE’s post to guide me. There were no nasty surprises requiring too much thought and the process was simple and straightforward.

Finally, was a new ADSB decoder that could be used with an RTLSDR device. Called Dump1090 it was written by Salvatore Sanfilippo that I saw mention of on Twitter – this was very simple to get going:

git clone git://github.com/antirez/dump1090.git

cd dump1090
make

Once the program was built, I particularly liked running Dump1090 in interactive mode with the RTLSDR dongle in one of the USB Hub slots connected to the Pi

./dump1090 –interactive

This produces a simple, but interesting list of aircraft that the the decoder is seeing. Unlike any of the other decoders I’ve used recently, it gives an interesting indication of the sheer volume of messages that are being decoded.

It was good fun getting these different programs working and remembering some of my lost Unix skills!

Thanks particularly to Pete 2E0SQL and Dave G4FRE for their inspiration for these experiments.

Tim Kirby, G4VXE, is a regular contributor to AmateurRadio.com and writes from Oxfordshire, England. Contact him at [email protected].

Just before the New Year my PC had what seems to be a software problem and I ended up losing all my data on my PC and had to start from scratch with a reformatted hard drive. I did not realize how much junk I had on my computer and that does explain why it was getting rather slow. Now that the hard drive is re-formatted and most (but not all) of my software is loaded back on I am able to get on the radio and have some fun!!! I still have some computer to radio and radio to computer communications to sort out but I felt it was time to take a break and just hobby.

Some of E77DX's antennas!!!

I had a look at the propagation and it looks not to bad at all I have not had that much time to really be paying attention to band conditions with all the "making the shack computer happy" again. Flux at 145 and sunspot in the 180's I thought WOW things are looking up! It was now time to turn on the K3 pump the power to a top end of 5 watts and let-r-go............
I was able to make a fast DX 599 and go report to E77DX in Bosnia and I check on QRZ.COM and he sure does have a wild setup!! Emir was coming in around an S3 and I had to use my APF to really pic him out of a rising noise floor. This was on 30m's and I seem to find this a really go to band for me. I then for some reason jumped down to 10m's and VA7WW was calling CQ and he was in around an S2 to S3 here

Now that is some great looking landscape!!

at VE3WDM. Bill had a good copy on me and we exchanged info and then conditions changed and we had
to cut the QSO short but it was nice to have a CW conversation as to the 599 and move on. At this moment I am on 10m's again with VFO A in my right ear listening to QX3XR and KR7Q in my left ear on another spot on 10m's. Well I just contacted Peter OX3XR in Greenland he gave me a 559.......radio is so much more fun than farting around with the computer....
Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

Over the past three days I have made two-way amateur radio contacts (a “QSO” to hams) via an unusual short wave propagation path – the long way, over the south pole – from my home in Glade Park, Colorado to amateur radio stations in the Arabian Peninsula, each day in the late morning my time.  Signals have been surprisingly strong and audible for hours.

Short wave radio signals usually follow the shortest path from point A to point B, the ‘great circle path.’  From my house to the United Arab Emirates this is approximately 13,000-km.  Since the circumference of the earth is just over 40,000-km the long path to the UAE is around 27,000-km and crosses the equator twice!  The DX Atlas Map below has markers for my home (QTH), where the map is centered, and the UAE and also shows the location of the sun, dusk/dawn zones and areas of darkness for 1744z on January 5, 2013 (this is the time for one of the YouTube videos I made of this event).

Here are the QSOs I’ve made over this path (so far, fingers crossed this path will be here tomorrow and beyond):

• Jan 3     1805z     A65BR     28076-kHz     JT65A
• Jan 4     1839z     A65BP     24893-kHz      CW
• Jan 4     1844z     A45XR     24902-kHz     CW
• Jan 5     1702z     A45XR     28009-kHz     CW

My four contacts were made with a simple vertical antenna and 100-watts transmitter power (except for the JT65A mode contact which was made with a mere 10-watts).  The footprint of the propagation was very specific – the southern Arabian/Persian Gulf area on one end and western North America on the other.  Here is what the A65BP DX Cluster spots looked like as of this morning.  You can get a feel for the where the signals were landing in this part of the world from the spotting stations’ locations:

Why did this path open now?  A recent spike in the solar flux above 140 helped refract the 25/28-MHz radio waves a long distance, a ‘quiet sun’ (low Kp and Ap indexes) helped the signals transverse the auroral zone around the south pole and a double crossing the trans-equatorial zone – where radio waves from the upper HF all way up to low UHF can get a turbo boost plus the seasonal geometry of the sun and earth which puts a lot of solar radiation in the southern hemisphere all played a part.  I wonder if higher solar flux would have resulted in a rare (for the USA) long path opening in the amateur 50-MHz (6 meter) band?

Here is a recording of A65BP operating from the United Arab Emirates with a great signal on 28,012.26-kHz as heard in Glade Park, Colorado (DM59pa) today 2013-Jan-05 morning at 1743z with a simple vertical antenna. The signal was propagating via long path over the south pole. A45XR was also strong on 10m CW on this path around this time. I completed QSOs with A65BP and A45XR on 24.9-MHz long path on January 4th and had a 28,076-kHz JT65A QSO with A65BR on January 3rd. Nice to hear some 10m long path in Cycle 24!

Here is a recording of A65BP operating from the United Arab Emirates just a little later with a great signal on 24,902.00-kHz, also captured with a simple vertical antenna.

These last few days have really lit a fire under me to get off my ass and build the 3-element 12-meter LFA Yagi and 5-element 10-meter LFA Yagi from InnovAntennas that are sitting in my shed.  If I can work stuff like this on my vertical what will I be able to do with a pair of state-of-art antennas?  Who cares that hasn’t been above freezing here since December 17th when there is DX to be worked!

(Sunday morning update – A92GR & VU2XO are audible on 10m SSB at approximately 1600z, looks like another good morning on the long path.)

Bill Hein, AA7XT, is a regular contributor to AmateurRadio.com and writes from Colorado, USA. He is co-owner of Force 12 and InnovAntennas. Contact him at [email protected].