Some new test signal software has been made available by Fulvio Cornetta via his website at:
http://www.webalice.it/fulvio.cornet...signalsgb.html
It runs on any computer running W2K or newer. It has a variety of test signals and includes a provision for typing in your call letters, name or whatever.
To get it down to TV rate, you'll need a scanconverter if your PC does not have an NTSC output.
Its very easy to use but most of all, its FREE.