Sending Christmas Greetings to the ISS

There was much media coverage in the UK of the “Santa pass” (Telegraph, Daily Mail) The International Space Station passed over the UK in the late afternoon and early evening on Christmas Eve and around 17:20GMT promised an especially bright display in the dark skies. So imaginatively we were asked to observe and imagine that the bright moving point of light was actually Santa off delivering his presents.

As luck would have much of the UK had a crystal clear sky and I even managed to get my 80 plus year old Mother-in-law out in the garden to watch the spectacle. She was impressed and it was great to overhear lots of excited children coming out in the nearby homes to watch Santa as he flew overhead.

Back in October 2013 after becoming a newly licensed radio amateur I managed to send APRS packets to the International Space Station which were digipeated and received back on earth by other operators. Back then I used a lowly Baofeng UV5R handheld and I decided to repeat the exercise this time using the FT857D (this time running around 20W) to talk to Santa!

The computer I used back then has been decommissioned so on the laptop I installed the UISS program from ON6MU which makes easy work of APRS to the ISS and instead of the cumbersome AGWPE I used the excellent soundcard modem from UZ7HO.

I attempted to send a message on the pass at 15:43 but failed completely, discovering I’d got my soundcard incorrectly set up. I corrected this and left the autobeacon mode running in UISS during the Santa pass and checking back much later could clearly see I’d sent and had a message repeated back from the ISS.

Checking the ariss website (www.ariss.net) I could see the repeated message had been received by another station and my position was showing up on the map (M0NRD)

I have successfully done it again today on Christmas Day! As the raw packets below confirm.

M0NRD>CQ,RS0ISS*,qAR,DM2RM:73' Happy Christmas from Andrew IO93OB
M0NRD>CQ,RS0ISS*,qAR,MB7USS:=5304.08N/00048.47W-73' Happy Christmas from Andrew
M0NRD>CQ,RS0ISS*,qAR,HG8GL-6:73' Happy Christmas from Andrew IO93OB

It was a nice achievement and another nice Christmas present was achieved early this morning while running WSPR on 40m, managing to get received in New Zealand

Anyway enjoy the rest of the festive season and I wish you all the best in 2015

My APRS broadcasts received by the ISS

This evening I managed to successfully send some APRS messages to the International Space Station that were successfully digirepeated. It might not be a major technical achievement but after monitoring and decoding many passes in the past to now actually send something myself 300 miles up to something traveling at 5 miles/second left me feeling a little chuffed!

I screen capped the evidence from the website http://ariss.net which documents Amateur Radio data digipeated by the ISS. In order to appear on the page, a position report in a valid APRS format must be received and then digipeated through the ISS system, then be heard by an internet gateway station, which then forwards it on to the APRS Internet System.

Okay it sounds a bit more impressive when put like that 😉

The map showing received stations, M6GTG is me!
The detail of my report
List of stations with time stamps, showing me!
List of digirepeated messages

The equipment I used was very similar to that I used for the APRS IGate setup last month.

It consists of a small embedded PC running embedded XP, the sound card output was connected to the microphone input of my Baofeng UV-5R+ operating in VOX mode set to 145.825MHz. The radio was connected through my power/SWR meter in to the X-50 antenna. I used the UV-5R+ instead of the UV-3R since it has a little more power and better audio. I had a SWR of around 1:1.2 and outputting 4W.

The software I used was UISS from ON6MNU and the AGWPE packet engine. It has taken a little time to work out how to setup UISS into auto-beacon mode and putting in the time of the next decent pass (approx 45 degrees elevation) I set it to broadcast position and text data messages every 30 seconds.

The embedded PC running UISS
UV5R+ in VOX mode on 145.825MHz
The power meter showed 4W output, SWR about 1:1.2

I stood out in the dark, hoping to see the ISS pass over but the cloud cover was too thick and monitored using a handheld scanner. I heard my transmissions obviously and the ISS broadcasts as it repeated received messages, but I didn’t know if any were mine till I got back to the PC.