When decoding utility signals I use either RadioRaft or HamComm. Both programs run from DOS. Radioraft is interesting because it decodes any number of utility signals automatically.
With HamComm you have to select with the keyboard the correct baud rate, etc. but it does have all the facilities for doing this and more.

The interface is connected from the audio-out of your radio and fed to either port one or port two on the the PC. Once this is done you select from the software which port you're connected to then you're ready to go.

The interface is the same as used for decoding Slow-Scan TV (SSTV). There are interesting utility signals scattered all over the short-wave spectrum and the table below shows a few frequencies worth listening out for.

We may be in the days of 'everything digital' but there are still thousands of utility signals waiting to be decoded on the HF bands. And you don't need a multi-squillion dollar setup to decode 'em. My RTTY decoding setup consist of the following...

• HF General-Coverage Receiver
• Homebrew'ed HamComm Interface
• HamComm 3.1 SoftWare
• 33MHz Low-Spec PC Running DOS O/S