For the past several months I've seen odd-patterned signals consisting groups of parallel lines of dots in the 8 - 9, 10- 11, and 14.5 - 15 MHz portion of the HF band. I'm using an Airspy HF + Discovery and am looking at the waterfall. The signals not always present, they come and go with band condx. Disconnecting the antenna makes them disappear so they're definitely legit. Been a SWL over 60 years and this one's got me stumped. Wonder if anyone's seen these on the band?
I've tried posting a .JPG image here but no luck, forgot how it's done, a senior moment I guess, hihi. Tnx and 73's.