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 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.

Still waiting! But did get a new toy

Everyday last week I have picked up the newly delivered post with growing anticipation only to be disappointed. I am still waiting for the official notification of my foundation pass from the RSGB so I can apply for my call sign. They do say it can take six days from when they receive the tests, so hopefully it will be early this week.

Something did turn up in the post on Saturday morning, I was awoken at 7:30am by a knock on the door, bleary eyed I took delivery of my latest purchase from eBay, a Baofeng UV-5R+ handheld. This is a Chinese made VHF/UHF dual-band FM transceiver suitable for the 2 metre and 70cm bands. The package came with an official Baofeng USB programming lead and a small handheld speaker/microphone that can be plugged into the main unit all for the pricely sum of £37 including postage.

I can admit now to already owning a Baofeng UV-3R which I have had for some time but have only ever used for receiving and the odd transmission on the PMR446 band. It cost about the same price and considered it a bargain then but on first impressions the UV-5R+ seems even more of one. It is a much more substantial device, it feels very solid in the hand. The display is bright and clear and the proper volume control and keypad make for a more pleasant experience, you can actually turn it down unlike the UV-3R which is deafening or off! It came with a proper drop in charger, a USB programming lead and a small hand-held speaker/microphone/PTT unit.
These units are just stop gaps until I get around to getting a decent amateur rig, the current front runner being the Yaesu FT-857D which is a nice small affordable(ish) unit giving me all-modes on HF and VHF/UHF. The 2013 National Hamfest which takes place in couple of weeks, right on my doorstep, could be a dangerous place for my credit card!
As well as having a chinwag I have already got a plans for a project to investigate APRS. I am hoping to use an old echolink/eQSO interface I built, around 10 years ago, linked to the UV-3R and a computer sound card. I am still investigating it but it seems the software which will be AGWPE to act as a TNC driven by the APRSISCE/32 the Amateur Radio client for windows.
I am especially looking forward to trying to contact the digi-repeater on board the International Space Station, some details here.