Receiving LES1 a satellite built in 1965!

A few weeks ago I read a news article about the miraculous reactivation of LES1, this satellite was built by the Massachusetts Institute of Technology and launched back in 1965. The satellite failed to reach its intended orbit owing to a wiring error and has been drifting out of control ever since, it was abandoned in 1967 as a piece of space junk but has seemingly begun transmitting again after 46 years.

Back in December Phil Williams G3YPQ from Cornwall noticed a peculiar signal and after some research determined it was LES1. The odd signal is probably caused by the satellite tumbling end over end every 4 seconds as the solar panels become shadowed by the engine. ‘This gives the signal a particularly ghostly sound as the voltage from the solar panels fluctuates’ Phil says. It is likely that the on board batteries have now disintegrated and some other component failure has caused the transmitter on 237Mhz, to start up when its in sunlight.

Eager to see if I could receive this ancient satellite I dug out an unused DAB 3-element antenna and mounted it on a tripod and successfully monitored two passes this afternoon.

I used my FUNCube Dongle (original version) and SDR-Radio V1.5 and this was the analysis of the resulting recorded IQ file for the pass that started around 17:30pm. You can clearly see the satellite signal as it undergoes Doppler shift and the four second regular frequency shift caused by the tumbling.

At its most northerly latitude the satellite orbit passes over North Africa, but due to its height has a longer orbit period than most other satellites and is receivable over much of Europe. How long it keeps transmitting is a mystery.

listen to ‘LES1 Signal’ on Audioboo

FITSAT-1 - Full telemetry decode achieved.

Had an excellent FITSAT-1 pass last night, successfully received nearly three full frames of CW telemetry.

The image above (from the heavens-above.com prediction site) shows a similar pass and illustrates the reception window which is just less than 8 minutes. Each frame of telemetry takes around 2.5 minutes to receive, so I was extremely happy with the results.

Again I recorded the pass using SDR-Radio and played back the doppler corrected IQ file later decoding with the MRP40 program, hear is a small video demonstrating the decoding process.



and this was the resulting telemetry data when run through the analyser program (see previous post).

---------------------------------------
FITSAT-1 NIWAKA Downlink CW Code
---------------------------------------
Input Data------------------
S1 :f00501bb
S2 :88db0101
S3 :02000102
S4 :1e20201f
S5 :1a12aae7
-------S1------
S-mater of 437MHz RX             :4.69[V]
Total Voltage of Solar cells       :0.1[V]
Total Current of Solar Cells       :0[mA]
Voltage of single cell battery     :3.65[V]
-------S2------
Current of single cell battery     :1054.69[mA]
Voltage of 3 series battery        :12.83[V]
Current of 3 series battery        :0[mA]
Voltage of 2.5V reference          :0.02[V]
-------S3------
Voltage of Solar cell + X          :0.07[V]
Voltage of Solar cell + Y          :0[V]
Voltage of Solar cell - X          :0.04[V]
Voltage of Solar cell - Y          :0.07[V]
-------S4------
Temperature of 3 series battery  　  :2.73[℃]
Temperature of single cell battery 　:6.25[℃]
Temperature of +Z side     　        :6.25[℃]
Temperature of –Z side        　    :4.49[℃]
-------S5------
S-meter of 1.2GHz RX                :0.46[V]
------Timestamp-----  
14day 3hour 49min 59sec

I have also uploaded a better recording of the audio.

FITSAT-1 CW Telemetry by nerdsville

Video of VO52(HAMSAT)

Due to work and family commitments and the currently inconvenient timing of the passes I really haven't had a serious attempt at receiving any of the downlinks from the numerous Cubesats launched on the Vega rocket back on Monday February 13.

I have managed to get some faint transmissions from what I believe is Masat-1 which has now been officially designated MagyarSat-OSCAR-72 (MO-72) I have also seen a number of other traces on the waterfall display of the sdr  (using the FUNCube dongle) They are in the correct frequency range and appear and disappear as the cluster of cubesats were predicted as passing overhead.

I have managed to make a video of  a pass of the SSB VO52(HAMSAT) downlink being received by the FCD this morning using just the antenna in the loft.



Operating a camera in one hand and trying to track the signal isn't that easy, but you get the idea!

I have got a chance this weekend to have a proper attempt at the Vega cubesats.

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.