Just discovered the JT65 Reverse Beacon mode (thanks Gary K7EK). After 2 days of activity here is a quick summary:

- The JT65 RB mode is RX only... so you just send RX spots to W6CQZ database... see http://www.w6cqz.org/ for more details. This said you may run QSO's, meanwhile reporting RX details to the DB. So something close to a conventional DX-cluster (with auto-spot ON)
- The main drawback of JT65 RB (in auto mode), is that it takes only the strongest station within the RX- monitored bandwidth . It also takes more bandwith, so only a limited number of stations in each period (basicaly only 1 at any given time... This said if you are at the station and have time to spend to click on traces... you may report more than one station in each period....)
- The main advantage (and a consequence of the a/m point) is that JT65A is more resistant than WSPR to polar flutter. For example the 40m path K7EK to F6IRF, proved to be unusable with WSPR due to polar flutter... (strong signal but no decode...).
- The JT65A-RB database is not searchable, there is no map available, etc... only the last spots, are visible at http://jt65.w6cqz.org/receptions.php
- JT65A being mainly a QSO mode, you sometimes don' t get the locator, or even the callsigns (when stations exchange working conditons, names, 73, etc...), and of course no indication of TX power... basicaly only the received report, "for your eyes only" !
- On the other hand, outside 30m there is more activity in JT than in WSPR (and stations active from PY, LU, ZS, DU etc...). This said, the main activity is on 14076, and I had to leave my RB on for 4 hours and announce it everywhere, before getting the 1st station to decode on 17m... (I was hearing the 4U1UN 17m beacon for quite some time !)
- JT65A is slightly less sensitive than WSPR (some 3dB), but the periods being shorter (45s vs 115), it is not a problem to run 3dB more...

That's it... as propagation tool, I still continue to prefer WSPR, but if this mode continues to be 30m only, I will drop it, like many others before me...

Come on guys, there is a life above 30m !!!
73's - Pat

PS: I have nothing against 30m, it is a nice band (I have produced several thousands of 30m spots myself)... just that I am interested by propagation, and that propagation is not limited to 30m propagation. Looking at the maps, or statistics it is quite obvious that the WSPR activity lacks some geographical and frequency diversity... isn't it ?