Are you saying that to get JT signal reports similar to what you are giving you have to run 60 watts out? I have noticed pretty much the same thing though I keep it to 30ish watts normally.
A lot of my signal reports are a lot less than the reports I give. I haven't done the math in quite a while but I think I'm consistently getting reports about 6 dB less than what I send. Sometimes the spread is much bigger.
For the longest time I thought that meant something was wrong but if I read you correctly, it actually might be that my Flex receiver is just that much better than most other receivers?
I'm giving a talk at Quartzfest next week on "how to get started in JT modes", and will be running live demonstrations on the special event station (usually W7Q) with my 6500 starting Sunday evening, probably on 20M.
We ran some A/B tests a couple of years ago with an IC7700 and a microham interface vs a 6700 and internal DAX. Invariably the 6700 outperformed the 7700 by about 3-6 dB on JT-65. Some of the gain advantage was explained by the lower internal phase noise of the 6700 but the rest likely came from avoidance of the external interface.
Signal reports are specified as signal-to-noise ratio (S/N) in dB, using a standard reference noise bandwidth of 2500 Hz. Thus, in example message at UTC 0003 above, K1ABC is telling G0XYZ that his signal is 19 dB below the noise power in bandwidth 2500 Hz. In the message at 0004, G0XYZ acknowledges receipt of that report and responds with a –22 dB signal report. JT65 reports are constrained to lie in the range –30 to –1 dB, and values are significantly compressed above about -10 dB. JT9 supports the extended range –50 to +49 dB and assigns more reliable numbers to relatively strong signals.Signals become visible on the waterfall around S/N = –26 dB and audible (to someone with very good hearing) around –15 dB. Thresholds for decodability are around -23 dB for JT4, –24 dB for JT65, –26 dB for JT9.
Note that in JT65 mode the reports are compressed up against an artificial -1 dB ceiling. This means that as the reported JT65 signal strength goes up, it means less and less. This is not the case in JT9, where positive reports do occur.
Reported signal strength is entirely a matter of how the signal propagates and the local receiving conditions. Pouring in lots of power may help a little, but brief band openings are probably more important. I have a number of JT65 and JT9 DX QSOs in my log that suddenly popped up out of no where and just as suddenly collapsed.
I suspect that the new decoder performs better at the lowest signal power levels and the JT65 lower limit has been extended downward somewhat.
Regardless, I think its safe to say that Flex radios are just about the best possible choice for operating in this mode.
http://www.frenning.dk/OZ1PIF_HOMEPAGE/SignaLinkUSB-mods.html, but as noted before, staying in the digital realm is a bonus for deeper noise decoding. I have yet to do long term listening on my Flex, as I am still in the "new radio" mode, and shut if off at bed time, rather than leaving it run all night, and see what I "catch" in the morning...
Interesting Experiment using PSKReports
1. Run CQ at Low Power... see how far they hear you
2. Run CQ at High Power (Tight XMT Filters and Low Drive Audio to reduce splatter) - See how far they hear you
3 Run CQ at High Power but don't adjust the filters or drive...see how far they hear you
I found that #2 easily went the furthest. YMMV