http://www.cs.helsinki.fi/u/okraisan/selostus2.mp3

Location telemetry from the helicopter?

Update: Apparently the video downlink to ground was transmitted using a transmitter similar to Nucomm Skymaster TX that is able to send live GPS coordinates. And this is how they seem to do it.

Update 2: Yes, it's 7-bit Bell 202 ASCII. I tried decoding it as 7-bit data earlier, ignoring parity, but must have gotten the bit order wrong! So I just chose a roundabout way and kept looking at the hex. When fully decoded, the stream says:

http://www.windytan.com/2014/02/mystery-signal-from-helicopter.html