On Sun, 21 Jun 2009 20:26:01 +0100, "tg" wrote:

I've picked up several frequencies on my scanner (here in the UK
midlands) that have this sound.
http://www.person.eclipse.co.uk/scanner/scan.htm
I didn't find anything on google. It's obviously some kind of data
transimission - can anyone tell me what it is exactly and if there's any
software available to decode it? Thanks for any pointers.


That is radio teletype. There are many modes of teletype: Here is a web site
with a pricey way to decode transmissions:
http://www.hoka.com/

This is a discussion group of people interested in monitoring so called
utility transmissions on HF.

http://groups.yahoo.com/group/utility_listening/

Good Luck,

--
Best Regards, Keith
http://home.comcast.net/~kilowattradio/