qam/qpsk on HF
 

I see numerous band limited noise-like signals on HF.
I'm tuned to one now at 14.730 MHz at 10:30 am pacific time.
They all seem to be bandwidth limited to about
2500 Hz, perfect for reception with a common
communications receiver.
Are these QAM or QPSK digital signals?
It seems like this would be a pretty secure cheap
way to send data long distance.
I gotta think people are doing that.
Does anybody know anything about it?
Who is sending? What the actual modulation is?

--
Ron Baker