Sunday 25 November 2012

500kHz WSPR 24 November

After watching the football decided to have a look on 600m using the HPSDR and the DX-B antenna for 160/80/40/30m which slopes to the north east at a height of 20'. WE6XGR (WE2XGR/6 but wspr takes twice as long to send that call!) said he would be QRV so first look there:-



0442 -19 -1.5   0.499500  0 WE6XGR FN12 50
0444 -23 -1.2   0.499500  0 WE6XGR FN12 50
0446 -21 -1.3   0.499500  0 WE6XGR FN12 50
0448 -21 -1.2   0.499500  0 WE6XGR FN12 50
0450 -22 -1.3   0.499500  0 WE6XGR FN12 50
0452 -22 -1.2   0.499500  0 WE6XGR FN12 50
0454 -26 -1.5   0.499500  0 WE6XGR FN12 50
0456 -26 -1.4   0.499500  0 WE6XGR FN12 50
0500 -26 -1.0   0.499500  0 WE6XGR FN12 50

after WE6XGR faded out just to check the receiver I retuned to WG2XIQ on 475.7kHz who was his usual strength

0504 -5 -0.5   0.474700  0 WG2XIQ EM12 30

Tuning around also heard WD2XSH/31 in VA and WE2XSH/7 in MS

To protect the wideband frontend of the HPSDR (0.1MHz to 55MHz) from the 40m QRSS transmissions I was making I had to use my 1kW rated 500kHz low pass filter in front of the receiver as it was the only suitable filter I had, the smaller ones are in England

28MHz WSPR 24 November


Lots of skip around the USA but not as much abroad

Saturday 24 November 2012

28MHz WSPR 23 November

Slightly better conditions, more European stations and  into south america
10m WSPR 11/23

Thursday 22 November 2012

Digital modes at Thanksgiving

Being Thanksgiving today time for some radio. I dusted off my ARDMEPT trannsmitter which is capable of multiband WSPR and QRSS running 250mW. Having the HF6V multiband Vertical switching antennas between bands was not an issue
I loaded the code for QRSS on 30m  30m WSPR and 10m WSPR. The results were interesting:-

10m WSPR
One station in England (G4HZW), two in Australia (VK7BO, VK2ZMT),  the rest in North America

30m WSPR
One station in Venezuela, the rest in North America

 Due to issues with grabbers hosted on QSL.net I used the new grabber in New mexico at http://qrss.nmsu.edu/SPOTD-30M.html

30m WSPR received in New Mexico

500kHz in USA

From the LF reflectors I had noticed new LF licences had been issued in the USA and new modes had appeared so it was time to take a look with my HPSDR and DX-B wire antenna

Monday night I looked on 474.2kHz and saw a signal from WG2XIQ (identified by his 12wpm ID) but couldnt decode as WSPR or the new JT9-2 digital mode, indeed they didnt look on the panadaptor like either mode. It was late so I switched off

Tuesday morning I tried the setup on 30m QRSS and noticed a lot of jitter on the Argo display. I was suspicious of the VAC connection between PowerSDR and WSJT-X so I ran a cable from the headphone output of the HPSDR to the computer mic input. QRSS looked fine and was easy to copy

Tuesday evening listened on WSPR on 474.2MHz. saw 2 signals

WG2XIQ in Fort Worth 0520 to 1432z

121121 814 30 0 -0.5 0.475686 WG2XIQ EM12 30 0 1 0

WG2XJM in PA from 0606 to 1156z

121121  820  8    -24      -0.5  0.475775  WG2XJM  EN91    37      0       1       0

Wednesday evening listened on the new JT9-2 (-2 is 2 second transmissions) on 474.2MHz. saw 2 signals

WG2XIQ in Fort Worth 2352 to 0532z

0820
10
-5
0.1
1420.6
0
14
WG2XIQ EM12

WG2XJM in PA was also seen at -33dB at 0254.

I also heard the "local" WD2XSH/6 and WD2XSH/7 beacons and the WD2XSH/31 beacon in Virginia

Sunday 11 November 2012

ADS-B aircraft reception

For a change today I hooked up my Modesbeast ADS-B aircraft receiver to my homebrew colinear, placed on the inside window sill and left it running for the day. The following shows the trails of the aircraft I decoded and plotted using planeplotter software:-


Surpising coverage. Flights to Guernsey/Jersey are seen along with planes over France, Belgium and Holland. More planes are seen East of me but I was surprised to see the planes due west of me which are blocked by the Malvern Hills

Sunday 4 November 2012

WSJT on Raspberry Pi using Raspbian



After the previous success on WSJT on UBUNTU it was next time to try WSJT on the Raspberry Pi. It only needed a few tweaks, all related to where portaudio19 was installed on the RPI:-

 svn co svn://svn.berlios.de/wsjt/trunk

 cd ../trunk

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

it did a whole load of things starting at "Compiling wsjt" and ended with "Installing into: /usr/local"

still in trunk:-:

make clean

make

after it finishes make sure you have permissions to execute  ../trunk/wsjt.py:-

sudo chmod 777 wsjt.py

Even though the serial port isnt used, WSJT still tries to talk to it so make sure /dev/ttyAMA0 permissions are set appropriately

to launch WSJT:-

./wsjt.py

Set the options. Make sure that the serial port is set to /dev/ttyAMA0, which is not the default

Saturday 3 November 2012

WSPR on a Raspberry Pi using Raspbian

I revisited this topic in my jan 28 2013 blog wspr-on-rpilapdock-under-raspian.html. The method below does not work due to issues with the "latest" revision of software on the svn. It works fine if revision 2840 is used

 Having got WSPR and WSJT working on my Ubuntu laptop, the next challenge was to get WSPR working on the more restricted  Raspberry Pi

First discovery was that a new version of the RPI image was available 2012-10-28-wheezy-raspbian.zip so that was downloaded and installed. At installation time I took the opportunity to overclock the board at 1GHz and in the same menu allow the memory space to fill ALL the memory card (if you dont you only have 2GB to use, even on a 16GB card!
Searching the internet I came across a blog "Compiling WSPR on a Raspberry Pi" at http://timbertops.co.uk/blog/?p=88  I also found some improvement pointers at http://www.vk2mev.net/?p=96

the "merged" steps (before I forgot how I did it) are:-




sudo apt-get update

sudo apt-get install build-essential subversion python2.7-dev python-numpy python-imaging-tk python-pmw libportaudio2 portaudio19-dev libsamplerate0-dev gfortran cl-fftw3 python-dev hamlib-utils

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

cd wspr


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

To make sure the hardware floating point processor is used (speeds up decode), the Makefile created by configure needs editing.

vi Makefile (edit wouldnt work on my machine on this file)
make sure line 5 reads:-
FFLAGS = -g -O2 -fno-range-check -ffixed-line-length-none -Wall -Wno-character-truncation -Wno-conversion -Wtabs -fPIC -mfloat-abi=hard
make sure line 9 reads:-
CFLAGS = -Wall -O0 -g -Wall -O0 -g -mfloat-abi=hard
next

sudo make 

programme created, now to consider hardware:-

The RPI has an audio output but no audio input. Some have used $5 USB soundcards, but I   did not have one in my collection. Fortunately I still had the I-MIC which I used with my Ipad to run ISDR. A web search revealed this should work with the RPI without any software updates. 
Plugging in the Imic it appeared in the list of audio playback and recording devices:- 
aplay -l **** List of PLAYBACK Hardware Devices **** card 0: ALSA [bcm2835 ALSA], device 0: bcm2835 ALSA [bcm2835 ALSA] Subdevices: 8/8 Subdevice #0: subdevice #0 Subdevice #1: subdevice #1 Subdevice #2: subdevice #2 Subdevice #3: subdevice #3 Subdevice #4: subdevice #4 Subdevice #5: subdevice #5 Subdevice #6: subdevice #6 Subdevice #7: subdevice #7 card 1: system [iMic USB audio system], device 0: USB Audio [USB Audio] Subdevices: 1/1 Subdevice #0: subdevice #0

arecord -l
**** List of CAPTURE Hardware Devices ****
card 1: system [iMic USB audio system], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

time to launch WSPR:-

wspr

The usual screen for WSPR3.0.1 appeared which looked like success. I selected the imic as   audio in and audio out source in options

Hooked it up to the K3 and got decodes!


Time to try Transmit. I usually key the transmitter via the radio RS232 port but although the RPI has an RS232 port it needed a level converter which I did not have. I resorted to   using the K3 VOX with success and my signal was successfully decoded:-

2012-11-03 16:10  G4FRE  14.097139  +1  0  IO82uc  5  IX1CKN  JN35pr  995  132 
 2012-11-03 16:10  G4FRE  14.097140  +3  0  IO82uc  5  EA2COA  IN83  961  184 
 2012-11-03 16:10  G4FRE  14.097113  -22  1  IO82uc  5  GW7PEO  IO83gh  156  330 
 2012-11-03 16:10  G4FRE  14.097110  -23  0  IO82uc  5  VK3GMZ  QF22sf  17060  70 
 2012-11-03 16:10  G4FRE  14.097129  -9  1  IO82uc  5  LB1A  JP50mt  1264  35 
 2012-11-03 16:10  G4FRE  14.097121  0  0  IO82uc  5  OH2MUI  KP10wj  1843  50 
 2012-11-03 16:10  G4FRE  14.097181  -8  0  IO82uc  5  EW6BN  KO45hm  2047  67 
 2012-11-03 16:10  G4FRE  14.097112  -2  0  IO82uc  5  LY2BOS  KO24or  1833  70 
 2012-11-03 16:10  G4FRE  14.097118  -25  0  IO82uc  5  VU2LID  MJ88lm  8527  93 
 2012-11-03 16:10  G4FRE  14.097096  -24  0  IO82uc  5  G4SFS  IO81qf  100  193 
 2012-11-03 16:10  G4FRE  14.097097  -9  -1  IO82uc  5  LA9JO  JP99gb  2177  22 
 2012-11-03 16:10  G4FRE  14.097086  -20  0  IO82uc  5  ON7KB  JO21ei  466  98 
 2012-11-03 16:10  G4FRE  14.097104  -20  1  IO82uc  5  DG0OPK  JO50gq  903  95 
 2012-11-03 16:10  G4FRE  14.097129  -21  0  IO82uc  5  DV1VHK  PK04ll  10830  55 
 2012-11-03 16:10  G4FRE  14.097104  -11  0  IO82uc  5  OH2MZA  KP20kf  1890  51 
 2012-11-03 16:10  G4FRE  14.097101  -5  0  IO82uc  5  OK/AD6XP  JN89ff  1355  96 
 2012-11-03 16:10  G4FRE  14.097115  -21  0  IO82uc  5  DU1MGA  PK04  10830  55 

One thing I did discover during the above process was that although the RPI sets its clock via NTP this only happens if the internet connection is available at boot time. If you   connect the internet lead after boot time the clock will be off
The observant will have noticed I did not add "dwc_otg.speed=1" to cmdline.txt as recommended by VK2MEV. I did try it once, but when booting,  the RPI didnt find the keyboard or USB mouse and hence wouldnt let me log in. I had to resort to removing the phrase from the SD card using my windows laptop to get it to boot properly