Hello Mike
I have found that JT65 provides a bit better than 10 dB more than a good cw
weak signal (read that as a real weak cw ) contact. I can copy signals by
ear that are listed as about -18 dB or more below the noise in JT-65, and
the rock bottom detection level for JT65 is about -28 or maybe a little more
with a few tricks. On HF, with all sorts of pops and squawks and
keyclicks/splatter, that 10 dB may not be a correct number. It could be
greater..I'm not sure. There is no way I could copy extremely weak CW with
QRM competing with the signal. The 10 dB number is only for listening to a
signal buried in galactic noise. In my opinion, copying CW in noise is much
more fun than reading callsigns on a monitor screen. There is no doubt
though that JT65 is a huge improvement for detecting weak signals. 10 dB is
a lot! JT65 cannot make up for a lack of propagation though!! (but what do I
know?) Does that help any?
Dave K1WHS
That's interesting, and brings to mind a question I've been wondering
about
for low-data-rate weak signal modes such as JT65, JT9 (which take 60
seconds to send a CQ), and QRSS (24 hours?!).
In the real world on 160, what would any of these modes really gain for an
operator already skilled in CW?
From reading posts about JT9 and JT65 on 160, the distance gain over
ordinary CW is really nothing to write home about. Does anyone have any
real-word experiences that say otherwise?
73, Mike
www.w0btu.com
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