After much twiddling of knobs and changing various parameters here and there, including on my Ten-Tec Jupiter, it started receiving signals. Pretty cool! Unlike PSK-31, all the JT-65 signals seem to pile on top of each other, but the software can sort them out. Tentatively, I tried answering a CQ. I had to let the system go a few rounds until I got the transmit levels sorted out, but before long, I answered KB7ZZ’s CQ and actually had a legitimate QSO! Woohoo!
JT-65 originated with moonbounce in mind and specializes in weak signal work. It isn’t really designed for ragchewing and pretty much limits you to the basics: callsign, signal strength (automatically determined by the decoding algorithm), and location (coded in the form of grid squares). It’s the hot new thing and is said to be great for working DX (long-distance contacts with hams in other countries). Indeed, I saw CQs from all over Europe, including Russia. I shall investigate this more!