Topband: New digital mode?
RadioXX at charter.net
Mon Oct 3 21:35:59 EDT 2016
Thanks for all the replies. I thought I had already tried everything
suggested, but maybe not, and now I am carefully going back through
everything again. Since these signals are on the band right now, I am
doing it as I am writing this. When listening for JT65 I always set
WZJT-X to decode both FT65 and JT9. I wasn't expecting this to be JT9,
so I'm testing again right now. It's not decoding anything, after many
Yesterday I tried for several hours trying all combinations of
bandwidth, USB, LSB, CW, and CW reverse and various modes in WSJTX.
Never decoded anything except when JT65 appeared and I did recognize
that. Most of the signals were 25 to 35 dB above the noise floor, so
the software had lots of signal to work with.
I'm not sure if this mode will be useful but it bugs me when I can't get
something like this to work.
Now trying WSPR-2 per Merv's instruction (K9FD/KH6 ). Rig on 1836.6
USB, no noise blankers and no noise reduction. And I just got my first
decode, W3PM. Thanks Merv!
Now to figure out why the setting I had before didn't work. Before I
didn't have the rig set to any particular frequency. I just set it to a
frequency that included the signal. So I will move the receiver up freq
a little. Still got several signals coming through well within the
bandpass, but no decodes. Amazing! All it took was moving the rig freq
up 200 Hz to kill all decodes.
So now setting the receiver back to 1836.6 and narrowing the passband
down to 800 Hz with the signals in the middle of the passband. It
works. So passband isn't a problem as long as the signal is within it.
Switching to CW mode with 1 KHz bandwidth and signals in the middle of
the passband, no decodes using either CW or CW reverse settings. Amazing
I don't know if this info was in the instructions on how to operate this
mode, or not, but it's obvious I don't follow instructions very well.
Thanks to all that replied.
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