Recent sporadic-E propagation openings on 6 meters and elsewhere have pointed up the need for a digital mode having faster turnaround time than currently available software versions offer. A recent WSJT-X reflector discussion allowed that, while the slow ’JT modes like JT65 and JT9 have excellent sensitivity, their 1-minute long transmissions may not permit completion of a contact when evanescent signals pop up and quickly disappear under certain E-skip conditions. MSK144 and the fast JT9 submodes allow much shorter transmissions, but they do not offer the multi-decode capability that JT65 users find so effective. Iain MacDonnell, N6ML, was among those remarking that, while the use of JT65 for working E-skip on 6 meters has really taken off, it’s too slow to be practical for openings that only last a couple of minutes or so.
Joe Dzekevich, K1YOW, of Harvard, Massachusetts, sounded a similar theme. “A few days ago we had a great opening on 6 meters, especially here in the New England USA area, given our latitude,” he noted. “I often find that often one cannot complete a QSO due to QSB and the ins and outs of Es. Yet, being a propagation buff, I love the idea that I can leave the rig on 50.276 in JT65 mode and then see who I hear throughout the day via PSK Reporter.”
WSJT-X developer Joe Taylor, K1JT, weighed in to express his appreciation to all who shared their ideas and experiences using JT9 and JT65 modes during recent multi-hop E-skip openings on 6 meters.
“We are very much aware that a mode with most of the excellent characteristics of JT65, but with faster turnaround time, would be a big winner in such situations,” Taylor commented on behalf of the WSJT-X development team. “We are experimenting with several such possibilities. Tentative goals include 15-second T/R sequences, sensitivity around S/N = –20 dB, occupied bandwidth less than that of JT65, and capability to decode as many as 10 or 20 signals in a 2-kHz bandwidth.”
But, Taylor added, developing new modes takes a lot of time, and results are not guaranteed. “We will report significant progress if and when available,” he pledged.
According to the WSJT-X page, JT9 is optimized for LF, MF, and HF, and it’s some 2 dB more sensitive than JT65 while using less than 10% of the bandwidth. Both JT9 and JT65 permit DX contacts at very low power levels and modest antennas. — Thanks to Joe Taylor, K1JT
How to get on JT65
David Clark DC PRO-X Hybrid ENC Technology in a Supra Aural (Rest-on-Ear) Headset Design Leading edge technology and sleek, supra aural design put the new DC PRO-X a generation ahead of any other aviation headset in its class. Hybrid Elec... Read more
AC6V’s GUIDE TO FM REPEATERS This book is six months in the writing and features the advice of several noted Amateurs and technical gurus. It is intended for those entering the world of FM Repeaters and Amateur Radio. The guide... Read more
In December, Joe Taylor, K1JT, released the latest version (1.7) of his WSJT-X software suite, designed to facilitate basic Amateur Radio communication using very weak signals (WSJT stands for “Weak Signal communication by K1JT”). Version 1... Read more
The new FTM-300DR provides stable and reliable 50W RF power output. As in recent YAESU mobile transceivers, the FTM-300DR is also equipped with a... Read more
Jim Heath W6LG talks about antenna gain using a light bulb. He shows a simple yagi and 2 brands of antenna rotator Read more