Re: VLF: Weekend carrier on 8270.005 Hz...

[Markus Vester <markusvester@aol.com>]

My 8270.0025 carrier from Nuremberg was on for seven hours until 20:30 UT. Three traces are now visible in the Todmorden spectrogram.

73, Markus


-----Ursprüngliche Mitteilung-----
Von: Markus Vester <markusvester@aol.com>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Sa, 11. Feb 2017 13:52
Betreff: Re: VLF: Weekend carrier on 8270.005 Hz...

I will try a short EbNaut sequence first

Frequency 8270.100 Hz,
5 characters 8K19A,
3 second symbols,
start 17-02-11 13:00:00, end 13:25:36

and later send some more carrier on 8270.0025.

Best 73,
Markus (DF6NM)

PS: On Stefan's grabber, there was a stable trace on 8270.0015 last night. Seems to be the same source as the slightly bent traces whiche were seen before in 424 uHz. A new station in the process of getting getting on air?



-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Sa, 11. Feb 2017 13:27
Betreff: VLF: Weekend carrier on 8270.005 Hz...

Hi VLF,

I'm running another carrier on 8270.005 Hz.

The antenna current is 700 mA, that's 100% of the capability of that
coil. That's about 29 kV across the antenna wire, about 75% of the
voltage limit.
The linear mode PA is now consuming 10.6 A at 25 V, i.e. 265W. I
estimate the PA losses are 65W, i.e. about 200W for the coil and ground
losses. These are 400 Ohm then. The loses of the warm coil are about 300
Ohm. So the ground losses are in a range of 100 Ohm, quite low!
Today i have covered the coil with a trash bag, just to be able to
continue transmitting during rain. The upwarming of the coil under this
bag causes an increase of the resistance which leads to a significant
increase of the needed TX power to hold the 700 mA level...

Markus, Uwe, do you want to join? It would be nice to see 3 peaks from
us showing on one of Paul's nice looking spectrum peaks! Furthermore,
RN3AUS is running spectrograms in 47 uHz and 180 uHz. These spectrograms
are now tracked by PPS+NMEA, whereas it was locked to GBZ/19.58 kHz
during the first detection of my signal.

If all works well i intend to run the carrier until monday morning.

73, Stefan

PS: There are a number of further 'newcomers' trying to detect a signal
on 8270 Hz these days, so its worth to be on the air...