A quick google search yielded the a schematic designed by KK6GIP. A good place to start.
A quick dig around in the junk box yielded the necessary components, a piece of recycled project board, an old busted iPhone headset, and the cheap headset that came with the radio. A few minutes later after some wire trimming and soldering – Voila! – an iPhone to BaoFeng audio interface.
I tuned the radio into 144.390 MHz (a common 2m APRS frequency) and transmitted an APRS data burst. This resulted in my coordinates and message being received by K2PUT (a local digipeater) which was forwarded to an internet gateway.
Ok that was fun. What next?
When the International Space Station isn’t using its ham radio for voice, it operates as a FM Packet Radio Digipeater on 145.825 MHz.
So I connected my homemade 2m yagi antenna, tuned to 145.825 and set my digipeater path to ‘VIA ARISS’.
Now all I had to do was wait for the ISS to pass overhead. The ISS completes around 15 orbits a day, so this didn’t take too long.
Using an iPad application called ProSatHD, I was able to determine down to the minute when and where the station would pass overhead.