ISS APRS/Packet

This week with the launch of the Russian Soyuz TMA-03M spacecraft to the International Space Station it occured to me that I have never seen it pass overhead or indeed made any effort to hear any transmissions from it. So off I went to the n2yo.com website to check the pass predictions for the week and was pleasantly surprised to discover that over the Christmas period there are a number of good evening passes (the potenitally visible ones are also listed on the Guardian website)

There are a multitude of  frequencies to potentially listen to, some of the operational ones could be quite interesting over the next few days, but at first I was interested in some of the ARISS frequencies.

On Tuesday (20th Dec) evening I popped outside with the 2Meter YAGI, Alinco DJ-X10  and my new found Satellite-AR Android App I did manage to see a faint moving point of light briefly as it came up over the horizon, but quickly lost it due to cloud cover and I think it passed into the Earth's shadow.

I was able to carry on tracking it using the Satellite-AR and picked up some very strong data bursts on 145.825MHz this is the APRS/Packet digirepeater. More details on the ARISS website. APRS in simple terms allows ham operators send a coded data message usually containing their GPS location, call sign and other information. This is received by the digirepeaters and rebroadcast, in the case of the ISS the digirepeater is moving around the earth at nearly 5 miles/second.

Last night (21st Dec) I used the loft mounted antenna and my Realistic PRO-2006 and captured and decoded some of the data on my PC using MultiPSK

Some of the data as it appeared in text form on the screen showing the coordinates, call signs and comments.

@215120h5218.35N/01624.62E-73! via ISS'yI1l -/]Paco en Leganes=
:F6GWB    :ack02!5214.25N/00043.40E`Aprx v2.02 SatGate@215356h5218.35N/01624.62E-73! via ISS=4542.75N/01142.00E`73' Via ISS de Cris {UISS52}=3919.07N/00259.59E`73' Via ISS {UISS52}!5310.76N/00532.86E- - 73 - Roland - www.pd2rld.nl -`vDjl -\`73's via ISS ea5hzz.raul@gmail.com_" :SP1TMN-6 :73{17 'vC$l S\]73 FOR ALL=
=4549.52N/01600.66E`[JN85AT] 73 via ISS de Robert - Zagreb - Croatia
!5310.76N/00532.86E- - 73 - Roland - www.pd2rld.nl -

  Some more good passes this evening that I might get a chance to capture with YAGI and weather permitting might get to see the point of light as it crosses the sky!