Tuesday 31 January 2012

Really annoying QRM Splatter!


Given the excellent positioning of the moon in the evening sky over the next few days I have been attempting some more decoding of weak signal EME (Earth-Moon-Earth) transmissions using my loft mounted homebrew wideband antenna, FUNCube dongle and SDR-Radio coupled with the MAP65-IQ application.

As you can see from last nights log, I had some success with this fairly rudimentary equipment, getting a reasonable number of decodes in a short space of time.

UTC Date: 2012 Jan 30
---------------------
  144.099 -215  0  0  0 -6.8    0  1 -26 2106  K1JT IW0DJB JN61        0 10  3
  144.100  320  0  2  0 -6.2    0  1 -24 2106  CQ VE4AAZ EN19          0 10  3
  144.100  352  0  1  1 -5.1    0  1 -25 2106  CQ DH6ICE JO61          0 10  3
  144.102  441  0  0  0  1.9    0  1**** 2106  RRR                     0  0  0
  144.104  301  0  1  0 -5.3    0  1 -24 2106  K1JT ZR6ABU KG33        0 10  3
  144.105  217  0  0  0  2.1    0  2**** 2106  RRR                     0  0  0
  144.107 -248  0  1  2 -4.5    0  1 -25 2106  CQ 9A1Z JN86            0 10  3
  144.107  -28  0  0  0  1.9    0  1**** 2106  RO                      0  0  0
  144.109 -470  0  0  0  1.9    0  1**** 2106  RO                      0  0  0
  144.110 -464 -4  1  0 -5.7    0  1 -23 2106  CQ OK1DCF JO80          0 10  3
  144.110   74  0  0  0 -4.1    0  1 -25 2106  K1JT N4LXB EM83         0 10  3
  144.110  440  3  1  2 -5.2    0  1 -25 2106  K1JT F9IE IN86          0 10  3
  144.114 -200 -2 -1  2 -5.2    0  1 -24 2106  K1JT EA6VQ JM19         0 10  3
  144.114  317  0  0  0  2.1    0  1**** 2106  73                      0  0  0
  144.115  113  0  0  0  2.1    0  1**** 2106  73                      0  0  0
  144.116  497  0  1  0 -6.5    0  2 -24 2106  K1JT N0AKC EN44         0 10  3
  144.117 -399  1  0  0 -5.2    0  2 -25 2106  CQ KB5WMY EM32          0 10  3
  144.117  136  0  0  0 -6.8    0  2 -23 2106  CQ W4AME EM75           0 10  3
  144.121  304  2  0 -1 -5.3    0  2 -26 2106  CQ EB2AYV IN83          0 10  3
  144.123  490  1 -3  0 -5.2    0  1 -25 2106  CQ EB2DTP IN82          0 10  3
  144.124 -115  3  0  1 -5.0    0  1 -26 2106  CQ DH8IAB JO30          0 10  3
  144.125  193 -1  0  0 -5.2    0  1 -24 2106  K1JT ES5RY KO38         0 10  3
  144.134 -463  1  0  1 -5.1    0  2 -25 2106  CQ IW0AKA JN61          0 10  3
  144.134 -419  0  0  0  2.1    0  2**** 2106  RO                      0  0  0
  144.134  -67  0  0  0  2.1    0  1**** 2106  RRR                     0  0  0
  144.136  316  0  0  0 -5.1    0  2 -25 2106  K1JT W6CAP DM14         0 10  3
  144.141 -202  0  0  0  1.9    0  2**** 2106  RRR                     0  0  0
  144.142  274  2  0  0 -7.0    0  1 -23 2106  CQ DC3VM JN39           0 10  3
  144.143 -180  1  0  1 -4.3    0  2 -25 2106  CQ W0DJM EN25           0 10  3
  144.143   33  4  0 -1 -7.0    0  1 -23 2106  CQ RK1B KO69            0 10  3
  144.143  155  6  0  0 -4.5    0  1 -24 2106  K1JT WA8CLT EN80        0 10  3
  144.143  274  7  0  0 -4.2    0  2 -18 2106  K1JT WD0APF EN10        0 10  3
  144.146  233 -1  0  0 -6.2    0  2 -23 2106  K1JT WN4KKN EM10        0 10  3
  144.148 -460  0  0  0  1.9    0  1**** 2106  RRR                     0  0  0
  144.149    5  2  0 -2 -4.2    0  1 -31 2107  K1JT K9JK EN52          0 10  3
  144.149   87 -1  0  2 -4.9    0  1 -30 2107  CQ YU1S JN94            0 10  3
  144.150  464  2  0  0 -4.2    0  2 -32 2107  K1JT WB0TEM EN12        0 10  3
  144.151 -323  0  0  0 -4.2    0  1 -31 2107  K1JT F5KCR JN26         0 10  3
  144.151  499  2  0  1 -5.3    0  1 -25 2107  CQ DJ9KV JN68           0 10  3
  144.152 -164 -1  1  1 -3.2    0  1 -37 2107  CQ DL3BWG JO62          0 10  3
  144.152   77  1  0  0 -6.0    0  1 -28 2107  CQ DH8IAB JO30          0 10  3
  144.152  115 -8  0  0 -5.6    0  2  -6 2107  CQ GW8ASA IO81          0 10  3
  144.152  263  4  0 -1 -4.7    0  1 -33 2107  CQ DH8IAB JO30          0 10  3
  144.153  -68  0  0  0  2.1    0  1**** 2107  RO                      0  0  0
  144.153  429 -1  0  0 -2.6    0  1 -25 2107  CQ DL3BWG JO62          0 10  3
  144.154   86 -1  0  0 -4.6    0  1 -36 2107  CQ RN6BN KN95           0 10  3
  144.155 -394 -3  0  0 -6.6    0  2 -36 2107  K1JT RL1X KO59          0 10  3
  144.155  164  0  0  0 -5.6    0  1 -23 2107  K1JT N5KWB EM32         0 10  3
  144.157 -179  0  0  0  1.9    0  2**** 2107  73                      0  0  0
  144.157    1  2 -1  3 -6.1    0  1 -25 2107  CQ ZS6MRK KG34          0 10  3
  144.157  193  0  0  0  1.9    0  2**** 2107  RRR                     0  0  0
  144.158  -81  2  0  0 -5.0    0  1 -23 2107  K1JT DL4SUN JO63        0 10  3
  144.158  -55  0  0  0  2.1    0  1**** 2107  73                      0  0  0
  144.099  206  1  0 -1 -5.0    0  1 -24 2114  CQ PA6T JO32            0 10  0
  144.100   23  2  0  1 -7.2    0  1 -24 2114  K1JT DK9ZY JO40         0 10  0
  144.100   55  1  0 -2 -5.2    0  1 -25 2114  K1JT K4DD EM60          0 10  0
  144.100  270  0  0  0  1.9    0  1**** 2114  RRR                     0  0  0
  144.100  477  2  0  0 -7.0    0  1 -22 2114  CQ N9XG EN60            0 10  0
  144.102 -152  0  0  0  1.8    0  7**** 2114  RRR                     0  0  0
  144.102    8  0  0  0  2.1    0  2**** 2114  73                      0  0  0
  144.102  331 -2 -1  1 -6.8    0  2 -25 2114  K1JT 9A1DFG JN85        0 10  0
  144.103 -111  0  0  0  1.8    0  1**** 2114  RRR                     0  0  0
  144.103  197  1  0  1 -5.7    0  2 -25 2114  K1JT K0RL EM49          0 10  0
  144.104 -364 -2  0  0 -6.7    0  1 -25 2114  K1JT IW1DJS JN35        0 10  0
  144.105 -382 -2  0  0 -5.3    0  1 -24 2114  K1JT RZ3QS KO91         0 10  0
  144.107  310 -1  0  0 -5.3    0  1 -25 2114  K1JT DJ8MS/P            0 10  0
  144.108 -138 -2 -1  0 -7.2    0  1 -24 2114  K1JT F1VJQ IN95         0 10  0
  144.110 -362  0  0  0  1.9    0  2**** 2114  RO                      0  0  0
  144.111 -124  0  0  0  2.5    0  2**** 2114  73                      0  0  0
  144.113 -401  0  0  0  1.9    0  1**** 2114  RO                      0  0  0
  144.113  102  1  0  0 -5.2    0  2 -24 2114  K1JT OE3R JN88          0 10  0
  144.117  -27  0  0  0  1.6    0  1**** 2114  RRR                     0  0  0
  144.118  -70  4 -3  0 -4.9    0  1 -24 2114  CQ LA3BO JO59           0 10  0
  144.118  156  2  0  0 -6.9    0  1 -24 2114  K1JT W9EME EN54         0 10  0
  144.118  357  2  0  0 -6.4    0  1 -24 2114  K1JT VE2WHZ FN08        0 10  0
  144.119 -486  0  0  0 -6.2    0  1 -22 2114  K1JT KI4M EM95          0 10  0
  144.119  278  0  0  0  1.9    0  2**** 2114  RO                      0  0  0
  144.120 -326 -2  0  0 -6.8    0  2 -23 2114  K1JT JO1LVZ PM95        0 10  0
  144.120  -13  2  1 -1 -5.1    0  1 -25 2114  CQ IK1EFM JN44          0 10  0
  144.121  -39  2  0  0 -6.6    0  3 -25 2114  CQ AF6O DM14            0 10  0
  144.121  135  0  0  0 -5.3    0  2 -25 2114  CQ M0VHF IO82           0 10  0
  144.122  225 -3  0 -2 -6.7    0  2 -25 2114  K1JT MM0BQI IO85        0 10  0
  144.123  376 -1  0  1 -6.5    0  1 -24 2114  CQ DL3BWG JO62          0 10  0
  144.124  141 -1  0  0 -6.6    0  1 -25 2114  CQ KB0CY DM79           0 10  0
  144.125  109  2  1  1 -4.8    0  2 -24 2114  K1JT AA1OV FN43         0 10  0
  144.127 -488 -2  0  0 -7.2    0  1 -25 2114  CQ ON1DSQ JO21          0 10  0
  144.127 -302 -2 -1 -1 -6.9    0  1 -26 2114  CQ ON1DSQ JO21          0 10  0
  144.128 -476  0  0  0  1.9    0  3**** 2114  73                      0  0  0
  144.128  -20  3  0  0 -4.9    0  1 -25 2114  CQ JR4BRS PM65          0 10  0
  144.132 -468 -4  0  1 -4.9    0  1 -24 2114  K1JT HV0A JN61          0 10  0
  144.132 -329  1  1  0 -5.1    0  1 -25 2114  K1JT DL9NDD JN59        0 10  0
  144.133   32  0  0  0  1.9    0  2**** 2115  73                      0  0  0
  144.134 -105  0  0  0  1.9    0  1**** 2115  RRR                     0  0  0
  144.135   81  0  0  0  2.1    0  1**** 2115  RRR                     0  0  0
  144.138  196  0  0  0 -6.5    0  1 -24 2115  CQ VA3NFA FN25          0 10  0
  144.140 -426  2  0  0 -5.1    0  2 -25 2115  CQ IK1EFM JN44          0 10  0
  144.140 -173  0  0  0  1.9    0  1**** 2115  RRR                     0  0  0
  144.143 -316  0  0  0  1.6    0  1**** 2115  RRR                     0  0  0
  144.146  140  0 -1 -1 -5.1    0  1 -25 2115  CQ GW0PZT IO72          0 10  0
  144.148  151  1  1 -1 -6.6    0  1 -27 2115  CQ PR8ZX GI64           0 10  0
  144.148  299  0  0  0  1.4    0  2**** 2115  RRR                     0  0  0
  144.150 -480  0  0  0  1.8    0  1**** 2115  73                      0  0  0
  144.151 -172  1  0  0 -7.0    0  1 -24 2115  CQ DF7RG JN68           0 10  0
  144.153  -19  0  0 -1 -6.3    0  1 -25 2115  CQ SV3KH KM07           0 10  0
  144.155  344  0  0  0  2.7    0  1**** 2115  RRR                     0  0  0
  144.156  225  0  0  0 -5.2    0  1 -32 2115  K1JT K4TAX EL96         0 10  0
  144.156  373  2  0  0 -6.7    0  1 -25 2115  K1JT 9A1CCB JN85        0 10  0
  144.157  -63  0  0  0  1.9    0  3**** 2115  RO                      0  0  0
  144.157  -17  4  0 -1 -6.5    0  1 -38 2115  CQ UT8AL KO61           0 10  0
  144.157   13  0  0  0  2.1    0  2**** 2115  RO                      0  0  0
  144.157   44  0  0  0 -6.8    0  1 -35 2115  CQ ON1DSQ JO21          0 10  0
  144.157  158  0  0  0 -6.9    0  2 -31 2115  CQ N0LL EM09            0 10  0
  144.157  324-18  0  0 -6.5    0  1 -13 2115  K1JT F1CCM IN93         0 10  0
  144.159 -281  0  0 -1 -6.4    0  1 -24 2115  K1JT DL8GAM JN37        0 10  0

The only problem is at the moment is an annoying source of interference that keeps popping up across the band!

I have struggled repeatedly monitoring 2 meter amateur radio (144-146Mhz) with my various receivers due to noise and now the FCD watefall display has illustrated exactly how bad it is.

Here is a small video capture of the waterfall display this evening across the 2 meter EME band (no sound)



This QRM 'splatter' is intermittent and when present slowly moves up and down the band. I suspect this might possibly be interference from someone using an evil PLT device (more details at http://www.rsgb.org/emc/the-rsgb-and-ofcom.php) but it could be something more mundane.

I have discovered my own router/access point generate a number of signals (the two distinct bands either end of the waterfall display in that video are from the router) but the source of the more annoying splatter is as yet unidentified.

Thursday 26 January 2012

January update

January has been a busy month. Work and social commitments aside I have also dusted off the Nintendo Wii and am currently addicted to completing The Legend of Zelda - Skyward Sword. I am not an avid player of video games but really enjoyed Twilight Princess so treated myself to the game just before Christmas but hadn't had chance to play it. It is great fun, but sucks hours of your time without realising it.

Most of my radio monitoring this month has been done with my lovely FUNCube Dongle (FCD) which I have used for terrestrial signals as well as those from space. The ability to adjust the width of the demodulation makes it ideal for data decoding, got some very good VHF ACARS results and it is interesting to see the wonderful patterns the pagers, trunking and telemetry signals make on the waterfall display

I captured another ARISS contact from the ISS on January 18th on my traditional scanner but I haven't got around to editing and uploading the audio as it was conducted in Dutch.I have also done some further decoding of APRS packets from the ISS.

I have been getting to grips with the FCD's various idiosyncrasies and issues. The main one being it is very susceptible to overloading and image problems.One important lesson I have learned is turning down the front end LNA (Low Noise Amplifier) section actually helps to bring in those weak signals as they aren't lost in the mush!

That revelation came about while attempting to listen to some earth-moon-earth transmissions 'moon bounce' inspired by this posting on the Southgate Amateur Radio News website. Using the MAP65-IQ software and SDR-Radio I did manage to successful decode a handful of messages over the course of a few evenings but ironically it was from the loft mounted antenna using my main PC rather than from the hand-held directional YAGI. I suspect this was mainly because the laptop I was using outdoors was struggling to run both applications. The neighbours must have thought I nuts standing out in the garden in the dark, lit only by the security lights waving around a big antenna on a wooden pole - apparently pointing it at the full moon!

I have also had a go at receiving the VO52 - HAMSAT amateur radio satellite with the FCD this week as it currently has a decent morning and evening pass. This is an interesting satellite as the transmissions are SSB rather than FM and during the pass the waterfall display is awash with lots of overlapping transmissions all shifting frequency with what sounded like lots of 'whistling'

You can get a idea of what it sounds like from these videos  http://www.southgatearc.org/news/april2010/hamsat_vo52_videos.htm

To be honest I was a bit confused by what I receiving until I saw these videos. What I believe is happening is the operators are trying to correct for the doppler and overshooting or undershooting. I will be making some videos myself once I have mastered the art of chasing the signal!

Monday 9 January 2012

ISS ARISS Contact January 9th 2011

This morning was an opportunity to hear ISS astronuat Dan Burbank, KC5ZSX as he took park in a planned ARISS contact.

At approximately 1014 UTC, an International Space Station (ISS) amateur radio contact took place with students at Descartes High School, located in Montigny-Le-Bretonneux, France.

The contact was in English and the downlink signal was audible in the British Isles and Europe on 145.800 MHz FM.

I was away from the shack so left the Realistic PRO2006 connected to the discone in the loft and set up an unattended recording of the audio on the computer.

I didn't get the full exchange but got over 5 minutes worth and this is the edited version, I have inserted silence during the 'uplink' transmission.

I am suffering from a great deal of interference on the 2 meter band at the moment but it doesn't spoil it too much.

ISS ARISS Contact January 09 2011 by nerdsville
There is a full video of the contact available here, starts at around the 27 minutes in..


Watch live video from f6krk2 on Justin.tv

Wednesday 4 January 2012

Farewell ARISSat-1

There has been no official announcement yet, but it appears that plucky satellite ARISSat-1 finally de-orbited early this morning.

The last frame of received telemetry on ARISSATTLM site hasn't changed since 06:02:14 UTC.

The DK3WN SatBlog posted the last report and some of the last heard voice telemetry earlier this morning. There is a post on the Yahoo FUNCube group from Konstantin RN3ZF claiming a very intermittent later contact at around 08:42, with links to some IQ wav files.

Several users on twitter have also reported no further contact with ARISSat-1, I monitored an pass myself earlier and got nothing.

I will miss it, I have enjoyed experimenting and receiving transmissions and I have learned a lot more about amateur satellites. It prompted me to join AMSAT-UK and am looking forward to having a go with the other satellites out there and the FUNCube project which will be launching later in the year.


Update, AMSAT-UK have confirmed ARISSat-1 is now silent key

Monday 2 January 2012

Howard Long G6VLB 2011 DCC FUNCUBE Dongle presentation

Howard Long G6VLB traveled to the 2011 ARRL/TAPR DCC from London to address the group on this project. He details the trials and tribulations behind designing and manufacturing what turned out to be an extremely popular product.

The primary aim of the FUNcube Dongle is to interest young students in science, satellites and radio. The FUNcube iteslf is a satellite that will be launched specifically to be monitored by all those dongles that Howard has sold.


ARISSat-1 SDR Videos

Just composed a couple of videos showing the use of the FUNCube Dongle Software Defined Radio to decode yesterdays data.

The first shows the FM decode



This video shows the CW/BPSK Telemetry beacon and what appears to be someone using the transponder, both these were using the USB modulation. It also demonstrates the problem of tracking because of the doppler effect.



Note both decodes were preformed on the captured IQ-Wave file.

The videos were created using CAMStudio

Sunday 1 January 2012

First FCD experiments

I was feeling shattered after a hectic Christmas and being back at work, so it was nice with the New Year break to have a chance to recover. I have spent the weekend around the house and so had a good chance to try out my FUNCube Dongle (FCD) to do some proper satellite reception!

First off I spent a while calibrated my dongle using the excellent user guides available on the yahoo group, and getting to grips with the excellent but somewhat daunting SDR-Radio application. 

I fired up another of my ancient laptops a Sony Vaio, with XP and a pitiful 512MB of RAM. It is a nice machine, with an excellent large display but is a little underpowered. However undeterred with the prospect of some timely satellite passes I installed the necessary software and set off to the summerhouse at the top of the garden with my YAGI and a warm coat.

NOAA Weather Satellites

As I posted about back in October I was hoping if I did get an SDR radio to capture some of the APT images broadcast by the NOAA polar orbiting weather satellites. (Noaa 15, 18 and 19 are currently active)



The SDR-Radio application has the facility to decode the noaa images directly and along with it's built in satellite prediction and doppler correction features it was fairly easy to get some decent images. The huge advantage of the SDR system is being able to alter the bandwidth to accommodate the 34KHz deviation required (as you can see in the image above)


The image above was captured on 31st December at 13:26 GMT from NOAA-19 on 137.100MHz, the left image is the IR, the right being the visible image. If you click to enlarge you can clearly see Spain and the Balearic Islands at the bottom, the UK and most of Northern Europe is covered in dense cloud and is rapidly going into shadow. There is some noise, caused in part by pager transmissions and some course manual doppler correction.


ARISSat-1

As I posted before Christmas this little satellite is still going strong but it's time is very short as reaches the atmosphere. I have been able to receive four afternoon passes in the last two days


As you can see from the image shows, the FCD makes the entire ARISSat-1 2 meter downlink band plan available. The slight slope shows the doppler effect.

On the left you can clearly see the Morse code beacon and the BPSK telemetry segment and the right the FM voice and SSTV transmission. I am really really pleased to have successfully managed to decode some telemetry frames before she meets her fiery death. The decode was done after the passes by processing the recorded IQ wav file. I probably have just one more day to have a chance to try to decode some live telemetry and hopefully forward it via the internet to ARISS.


It goes without saying I have some excellent audio and decoded a couple of SSTV images too.


I love my new toy!