Re: LF: 2200m Trans-Atlantic QSO dream...

[Markus Vester <markusvester@aol.com>]

Hi Rob,

if you decided to go somewhere between 137445 and 137555 Hz we could pick it up here using the already running SpecLab instances for opds.

73, Markus (DF6NM) 


-----Ursprüngliche Mitteilung-----
Von: Rob Renoud <k3rwr@md.metrocast.net>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Do, 22. Mrz 2018 23:45
Betreff: Re: LF: 2200m Trans-Atlantic QSO dream...

Stefan,

As this is an amateur radio transmission, the minimum message should be my 5 character amateur call sign, k3rwr.

Your  suggestion in a previous post was 1/8K=19 Coding; CRC 24, 3 sec Period with a resulting transmission period of 28:48.  Is this still good even though the 3 sec period may be a bit longer than is optimum for 2200m.  Any other suggestions?

I will transmit on 137.395 KHz with 1W EIRP.  Transmissions will start once I reconfigure the TX hardware and verify that the EbNaut signal is being properly modulated and transmitted.  I will post when the station is up and operating.

Tnx & 73,

Rob - K3RWR

On Mar 22, 2018, at 17:35, DK7FC <selberdenken@posteo.de> wrote:

Hi Rob,

Indeed, i have a suggestion. If you can transmit EbNaut messages, then let's try if it works. My RX is not overloaded any more. Due to the high QRN i gave up with the 17 kHz TA attempt . Last night i copied N1BUG in DFCW-60, maybe 10 dB in 22 mHz in the best times.
If you could run a beacon transmission, repeating each 30 minutes, using these settings: http://abelian.org/ebnaut/calc.php?sndb=10&snbws=0.022&snmps=&code=16K21&sp=2&crc=18&nc=3&submit=Calculate
with a content that makes some sense (like 'YES' rather than 'T.4'), then i would try to decode you.

73, Stefan


Am 20.03.2018 12:17, schrieb Rob Renoud:

Hi LF’ers,

My LF station TX and RX hardware support EbNaut requirements and I currently have EbNaut TX capability implemented and tested into a dummy load.  Am working to implement EbNaut RX software and decode capability.  Expect it will be several weeks before that capability is functional and tested as I’m still learning what is required and how to implement it.

I do agree that EbNaut is most excellent for experimentation and possibly QSOs on LF.  I believe the LF community should formulate an initial signal configuration for development and testing and one that will possibly support minimum QSO requirements as well.  I am not smart enough about EbNaut at this point to offer any suggestions or make any recommendations about signal configurations.

I am also available to put a EbNaut signal at 1W EIRP on LF from my QTH at FM18qi while I continue implementing full EbNaut RX and decode capability.

All ideas, suggestions and recommendations welcome!

73,

Rob - K3RWR

On Mar 20, 2018, at 05:08, VIGILANT Luis Fernández <luis@vigilant.es> wrote:

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