Paul,
Can you combine two transmissions on different frequencies or will that
cause trouble? I changed the frequency for the tomorrows carrier
between 8...17 UTC to 2970.005 Hz now but i could turn it back as well.
Oh yes, that may be a good idea anyway because Renato is watching in 5
uHz: http://www.webalice.it/rromero/live_cumiana/last-LFtest_2970.jpg
One week is just a few pixels long there, so i should stay on 2970.000
Hz for the carriers. So i hereby change the transmission plan...
73, Stefan
Am 20.01.2017 16:17, schrieb DK7FC:
...sorry i just see that my frequency is 2970.000 Hz, not 2970.005 Hz
as announced...
73, Stefan
Am 20.01.2017 14:53, schrieb DK7FC:
Am 19.01.2017 22:54, schrieb Paul Nicholson:
Looks good Stefan. I'll be looking for your signals.
Is there already a visible peak? The ERP is 2.8 uW. The carrier is now
running since almost 6 hours. I'm curious! Also it is interesting that
you can find optimised settings relative to 8270 Hz. I don't yet
understand why it should make a difference to duplicate the stream and
get and apply the blanker from and to different filter settings on the
separate channels. Exiting stuff to experiment with.
BTW, it is always a bit strange to claim to do the first whatever
(records...), but a few years ago the computer technique was not as
developed to handle modes like 16K25A. So can we conclude that it was impossible
to manage a message transfer over several 100 km on the lower VLF (
< 10 kHz ) with such power levels?
The PC causes a lot of phase glitches which are corrected immediately
but one can see a noise spectrum at -20 dBc :-/ I just didn't find the
time to prepare a better setup during the last days but i'm already
working on it...
73, Stefan
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