Re: LF: VLF/ULF activity weekend 21th/22th

[Markus Vester <markusvester@aol.com>]

Hi Stefan,

in principle, combining transmissions from different frequencies should be possible, as long as a predefined common reference time is used for the phase  When using SpecLab's GPS-phaselock, the oscillator phase for any frequency will always start from 0 degrees at midnight UT.

So you mean that all your transmissions (both carrier and EbNaut, how about DFCW?) this weekend will be on 2970.000 Hz?

Best 73,
Markus

-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Fr, 20. Jan 2017 16:51
Betreff: Re: LF: VLF/ULF activity weekend 21th/22th

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