Hi Don,
i think you have heard JT-65 transmissions. The K1JT Software WSJT-X can decode JT-65 ans JT-9 signals if you set your trx to 3576 (JT-9) or 3578 (JT65) as dial frequency in USB .....
The K1JT software has "occupied" this frequencies in the 80 m band
The melodic transmission is JT-65, JT-9 is more a verry small audio signal and you can´t hear so much changes in the NF frequency as in JT65 ....
For decoding tests connect your transceivers audio out to the microphone input of your soundcard and setup the software to this audio port. For transmit and receive its better to use a digital soundcard modem like a signalink USB or equivalent .....
I have experimented with all the different digital modes and it´s nice to see what distances are possible with power below 5 watts .... but also there are "crocodiles" with 50 or more watts power