I just learned about this forum through Youtube. Very interesting.
On October 7, 2018, at 1200 Z, while scanning for something to listen to, I picked up a bunch of guys on a net at 4.875 MHz., upper sideband. None of them were using a recognizable U.S. callsign. I could only write down what I took to be the net control operator. He signed- "AFS4FL". Nothing showed on a QRZ search. The topic of the net escaped me. They did seem to be talking about computer software at one point. I have heard other such nets which occurred just above the 80 meter band. They also used callsigns which were untraceable. Has anyone heard these guys around 4 MHz?