RE: [english 100%] Re: LF: 2200m Trans-Atlantic QSO dream...

[VIGILANT Luis Fernández <luis@vigilant.es>]

Hi Domenico, LF

 

I agree with you that EbNaut is the way to go for DX in LF. And QSOs can be made using short symbol durations at least equal to a long QRSS mode

Would be interesting if you recall the modes and time windows involved in that QSOs that took place in LF

 

But (at least muy experience, for a dummy and NON Lynux user) the different software packages needed and the lack of clear descriptions on how to

setup all the switches is a BIG problem and scares most OMs. The reward is to gain a LOT of dBs using the same station setup. So it really worths the effort

 

>> Of course, i'm also at disposal to put on air a small EbNaut signal on LF from my locator JN80nu

 

Please do it. Would be very important to get your EbNaut transmissions in LF as a reference. Specially to check if one can do it with an stable receiver

but not GPSDO disciplined. This last step is complicated for many receivers and not easy for many OMs. I’m using Perseus SDR which needs a GPSDO at

88MHz, but the existing TCXO looks very stable and think would work just determining the QRG shift and compensating for that

 

>>I believe that using EbNaut on LF (i.e. dealing with more robust signals than VLF) can be a very good training for acquiring the skill necessary to use EbNaut on VLF.

Absolutely agree ! J

 

73 de Luis

EA5DOM

 

De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de Domenico IZ7SLZ
Enviado el: martes, 20 de marzo de 2018 0:17
Para: rsgb_lf_group@blacksheep.org
Asunto: Re: [english 100%] Re: LF: 2200m Trans-Atlantic QSO dream...

 

Hi LF'ers

i suggest to the operators that are looking for any kind of ancient software for a T/A two-way contact, to have a look at

EbNaut.

EbNaut is a bpsk mode with FEC designed by Paul Nicholson for the VLF world.
But two years ago some EbNaut QSO's took place on LF between EU stations using short symbol durations. Signals from VO1NA have been nicely decoded even in Italy and also

a signal from DF6NM and IW4DXW have been decoded at VO1NA (without having a disciplinated oscillator at RX side).

See Paul Nicholson's Log:  http://abelian.org/vlf/amateur-radio/

So, i think that  a two-way QSO is possibile with EbNaut even in this coming Spring.

For starting this FB mode, it is necessary, as first step,  to achieve a good frequency precision with the RTX radios. This, sometime,  can be easly achieved by building some reference oscillators that use cheap GPS solutions.

Here, i've built a 10 MHz reference oscillator with a PLL locked with a 10 kHz coming from a GPS. This 10 MHz  reference signal goes to my RX and to the Exciter. Some 'scrapped' 10 MHz /GPS reference oscillators are on the market and easy to found.

Then you have to deal with different softwares.

For Windows' users, we can use Paul Nicholson's EbNaut-tx and EbNaut-rx together with other necessary programs as SpectrumLab and the DF6NM's tools.
But if you are using Linux (Ubuntu,...) , then  'vlfrx-tools' is the only fb suite needed for managing EbNaut Linux native program.

This mode is not well documented. Some EbNauters already wrote useful instructions. But i think that 'live' assistance on this mail reflector can help more: Questions from who is trying to use EbNaut and the answers from the Group can be more useful.

 

So i'm at disposal if some operator wants to try this mode.

Some month ago i have built-up a program for  auto-decoding EbNaut transmissions scheduled at certain time and frequencies (see the log on  http://www.qsl.net/i/iz7slz/EBNAUT/DECODED.TXT)

This setup can be again on-line if needed, also with different settings.

Of course, i'm also at disposal to put on air a small EbNaut signal on LF from my locator JN80nu.

I believe that using EbNaut on LF (i.e. dealing with more robust signals than VLF) can be a very good training for acquiring the skill necessary to use EbNaut on VLF.

73, Domenico IZ7SLZ