On being able to hear signals at -12 to -17 dB on FT8, I do broadly agree. A CW
signal at those levels would be easily heard and copied by any decent CW
operator.
I think a lot of the FT8 “processing gain” claims, assumes a really poor CW
operator. A 0dB FT8 signal is not at noise level, it is way way above noise
level.
That said, this morning at my sunrise (noon in Europe) I was printing Italian
stations on 40M FT8 and I was being decoded in Europe too, often at the -22 to
-24 dB level. (I was barefoot and I’m assuming the italiAns too). Those are
levels below what I can hear or copy on CW. I can work Europe midday on 40CW in
winter but not so easy in spring or summer.
Tim N3QE
> On Apr 22, 2018, at 10:17 AM, David Olean <k1whs@metrocast.net> wrote:
>
> I have been playing around with FT8 on 160M and am a bit puzzled. I have made
> plenty of contacts, but with many stations, it seems to require an inordinate
> amount of power to get their attention, or they do not respond at all. I also
> have noted that I can hear in a 2.8 kHz passband, signals that register from
> -12 to -17 dB. About the weakest that I see is a bit more than -20 dB. Does
> this mean that FT8 is only a few dB better than CW? I have my time set
> accurately and I try to place my TX signal away from whomever I am calling on
> a clear spot on my waterfall.
>
> Some stations are easy to work, and I have worked across the country (FN43 to
> a CM grid) running just 1 watt. It just seems that there are many stations
> that are not hearing much, but are making plenty of noise. Am I wrong?
>
> I am working on cleaning up my 160 setup and have 8 beverages running and
> they are all pretty quiet now that I installed plenty of ferrite chokes
> around on the RG-6 feed lines. I am looking forward to next fall and winter.
>
> 73
>
> Dave K1WHS
>
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