Автор Тема: ULF: Carrier on 2970.01 Hz - Успешный эксперимент DK7FC  (Прочитано 274 раз)

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Hello Markus, ULF,

The carrier was stopped after 2 hours (13:17 UTC).
What a great result! Again i did not expect such a S/N in 424 uHz at DL0AO. The QRB is 283 km, http://k7fry.com/grid/?qth=KO02MD&from=JN39WI
With that SNR and dureation, we could have transferred a 50 character EbNaut message on that frequency!
It is the new lowest frequency for DL0AO (amateur signal detection), so congrats to that!
That SNR indicates that even lower frequencies could be detected at DL0AO. Maybe it is worth to try 970 Hz again? So far the best distance on frequencies below 2.97 kHz is the 57.6 km path between here and my tree. At 1/3 of the frequency, do we expect about 10 dB less SNR? What about the local noise situation? 10 dB in 424 uHz, that would be fine.
If i would be even more crazy, i would buy another 120 Ah accu and build a stronger DC/DC converter and then run 1 kW from there. Everything is possible! But there is another idea that i will follow, which can improve the antenna efficiency a lot...

So, thanks to the crew for operating the RX site at DL0AO and the grabber service and these very good results in the end of the year!

73, Stefan

Am 30.12.2018 13:24, schrieb Markus Vester:

     Wow, a 20 dB peak on the DL0AO grabber !!!

    https://vlf.u01.de/
    https://vlf.u01.de/VLFgrabber/vlf5.jpg

    Congratulations to Stefan and the DL0AO crew!

    Best 73,
    Markus

    -----Ursprüngliche Mitteilung-----
    An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
    Verschickt: So, 30. Dez 2018 12:40
    Betreff: ULF: Carrier on 2970.01 Hz

    Hi ULF,

    The accu is fully recharged and i am on the hill again, transmitting on
    the ground loop antenna. This time, the accu has even more power. The TX
    power is 520 W (!), the DC measurement tells i need just 64 V for 1 A,
    and now, at 2970.01 Hz i am getting a record antenna current of 2.75 A!!
    The carrier ison the air since 11:17 UTC and i intend to run it for 2
    hours again, like yesterday.

    Reports are welcome :-)


    73, Stefan
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