Am 05.02.2017 17:31, schrieb Paul Nicholson:
Not significant: if I do a wide spectrum there are plenty
of peaks of similar or greater height. But it counts as
'interesting' because it's on the right frequency.
Hmm, plenty of peaks, sure, but not plenty of dashes, sharp dashes of
high SNR (white colour in the spectrum at
http://www.webalice.it/rromero/live_cumiana/last-LFtest_2970.jpg ) which
start exactly on the expected time and frequency.
The latest pixel is not so strong unfortunately, probably due to QRN.
But i bet the next ones will be, again.
And i bet the dash will end right after one week, just a dash between
two time makers. I intend to transmit one week exactly. And i increased
the antenna current to 170 mA a few hours ago. Yesterday it was quite
stormy and rainy and i transmitted anyway. Today, a visual inspection
showed no sign of HV stress, again, so things may be less critical than
expected. 150 mA to 170 mA, that's 1 dB at least.
From the early LF times we learned to read the weakest signals in QRSS
or DFCW. The complete spectrogram means information. And the peak hold
graph in the spectrum (green) shows that there only 3 peaks which have
the same strength or a higher strength. And these peaks are rather
blotches :-)
Anyway, a higher significance is desirable, thus i will run the
transmission a few days longer. Then we will see if its confirmed. A
frequency step will of course help even more to get a clear ID, but that
takes serveral days more then. So, we will see...
73, Stefan
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