Re: LF: EA5DOM-->FR5DH MF spots

[Andy Talbot <andy.g4jnt@gmail.com>]

Time lapse video ?

Many, many years ago when I was experimenting on 73kHz , G3PLX wrote the first recording and decimation software that could reduce an off air signal to a few milli Hz bandwidth, sampled in I/Q at a few Hz sampling rate (All pre-sound card days, using a Motorola DSP evaluation kit) .    The I/Q files could be saved for subsequent analysis - a bit like that used for Ebnaut, now.  This was the first QRSS

One trick I did was to take these recorded files, play them back at, say, 1000 times the sampling rate then upconvert to audio.    The resulting QRSS signal at 30 second dots then became 30ms dots or around 36 WPM morse

I then did this on an ionospheric broadcast carrier recorded overnight.    The resulting multipath and Doppler, when multiplied by 1000 times and converted gave the most amazing whale like 'natural' sounds I've heard. The sound of the ionosphere.  Unfortunately I've lost the .WAVs of that, and currently have no means to record HF signals in a narrow bandwidth to I/Q files.  (I have highly stable Caesium or GPS locked LF and microwave receivers, but not set up for locking a receiver at HF)

Andy

www.g4jnt.com

On 25 May 2018 at 12:54, DK7FC <selberdenken@posteo.de> wrote:

Hi Luis, LF,

The upper end of the spectrum is much more popular somehow.
Such videos would also be helpful to rise the interest in LF, but i don't know a similar one, except the SAQ and other commercial stuff of course.

On the other side, watching a video showing a "CQ EA5DOM" coming in in QRSS-6000 may take a bit long...
But certainly we could also offer fascinating videos showing what we do...

73, Stefan

Am 25.05.2018 13:06, schrieb VIGILANT Luis Fernández:

Hi Andy

 

We do! J

 

Last ODX two weeks ago was 303km in 47GHz

And also in digimodes, FT4 and Opera, but we didn’t try FT8

 

There is also a video if you want to see the opposite side of the spectrum going on

https://www.youtube.com/watch?v=INw8IJjn_LE

 

73 de Luis

EA5DOM

 

De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de Andy Talbot
Enviado el: viernes, 25 de mayo de 2018 12:47
Para: LineOne <rsgb_lf_group@blacksheep.org>
Asunto: Re: LF: EA5DOM-->FR5DH MF spots

 

You could always try the microwave bands

No dependence on the ionosphere

Too frequency-unstable to support FT8

Equipment home-brewed

Just as much fun...

 

Andy

www.g4jnt.com

 

 

On 25 May 2018 at 11:40, VIGILANT Luis Fernández <luis@vigilant.es> wrote:

Hi Pascal, MF

 

Uncharted territory. Or better said,  it was a very well known band in the past and now we have to re-discover

Who knows ?

 

The only CERTAIN is that all the radio universe will collapse into a single black FT8 hole  ;-)

 

73 de Luis

EA5DOM

 

De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de Pascal Deveaux
Enviado el: viernes, 25 de mayo de 2018 11:54
Para: rsgb_lf_group@blacksheep.org
Asunto: Re: LF: EA5DOM-->FR5DH MF spots

 

hello Luis, MF,
What will happen after the solstice? Will we have less luck?

Le 25 mai 2018 12:40:50 GMT+04:00, "VIGILANT Luis Fernández" <luis@vigilant.es> a écrit :

Hi  MF

 

Last night two unique decodes from Pascal, FR5DH. There were no decodes since may 21th

 

2018-05-25 01:30	EA5DOM	0.475608	-30	0	IM98xn	1	FR5DH	LG78pw	8783	129
2018-05-24 22:30	EA5DOM	0.475608	-26	0	IM98xn	1	FR5DH	LG78pw	8783	129

 

The DST has been high this days but there were many Solar X ray flares untill this settle down yesterday

 

Almost one moth for solstice and counting ! ;-)

 

73 de Luis

EA5DOM

 

De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de VIGILANT Luis Fernández
Enviado el: lunes, 21 de mayo de 2018 10:47
Para: rsgb_lf_group@blacksheep.org
Asunto: LF: RV: EA5DOM-->FR5DH 16spots last night

 

Hi MF

 

On more night of good conditions as DST keeps up http://wdc.kugi.kyoto-u.ac.jp/dst_realtime/presentmonth/

 

2018-05-21 01:20  EA5DOM  0.475608  -31  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-21 00:20  EA5DOM  0.475608  -29  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-20 23:50  EA5DOM  0.475608  -30  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-20 23:40  EA5DOM  0.475608  -30  0  IM98xn  1  FR5DH  LG78pw  8783  129

2018-05-20 23:10  EA5DOM  0.475608  -24  0  IM98xn  1  FR5DH  LG78pw  8783  129 

2018-05-20 23:00  EA5DOM  0.475608  -29  0  IM98xn  1  FR5DH  LG78pw  8783  129 

 

73 de Luis

EA5DOM

 

De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de VIGILANT Luis Fernández
Enviado el: domingo, 20 de mayo de 2018 13:08
Para: rsgb_lf_group@blacksheep.org
Asunto: LF: Re: EA5DOM-->FR5DH 16spots last night

 

Hi Pascal, MF

 

Last night we got some spots again

 

2018-05-20 01:40  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-20 01:20  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-20 01:00  EA5DOM  0.475608  -30  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-19 23:40  EA5DOM  0.475608  -32  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-19 21:30  EA5DOM  0.475608  -30  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-19 21:20  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-19 21:00  EA5DOM  0.475608  -30  0  IM98xn  1  FR5DH  LG78pw  8783  129  

2018-05-19 20:10  EA5DOM  0.475608  -31  0  IM98xn  1  FR5DH  LG78pw  8783  129 

 

I'm afraid (and really hope) that there is no correlation between earthquakes and MF propagation

 

But really wondering why I'm getting so good chances in this path. It is not by brute force and ERP power

So, the other possibility is antenna radiation pattern in vertical plane. The 90m vertical has probably a

very low radiation pattern. And at sea coast that means even more chances to get a very flat take off

angle to FR5. So low that may be I can reach there with four hops instead of five, which would be the

case for an average antenna with higer radiation angle

 

Four hops for 8783Km distance is about 2196Km per hop. Which is under the theoretical maximum

of 2235Km for an E layer situated at 100Km height

 

Path profile from here to Reunion, providing four 2196Km hops shows that first hop would land in south

Libya desert area, second in Sudan desert and third into the ocean, not far away from the coast of Kenia

That third bouncing in sea water would be a bonus for a weak signal to reach Reunion in the next bounce at 

decodable levels. With five shorter hops the third would land on ground and the extra attenuation may

left no much for a fourth hop to the ocean and then a five one

 

This are just my thoughts. Would be interesting to know experts opinion

 

73 de Luis

EA5DOM

---

De: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] en nombre de Pascal Deveaux [fr5dh@hotmail.com]
Enviado: sábado, 19 de mayo de 2018 7:50
Para: rsgb_lf_group@blacksheep.org
Asunto: LF: EA5DOM-->FR5DH 16spots last night

Hi MF,
I am not a specialist in the MF propagation and earthquakes, but I ask if the recent earthquakes in Mayotte Island have influenced the reception here. Mayotte is on the path between EA and FR:


 2018-05-19 02:20  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-19 01:50  EA5DOM  0.475608  -26  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-19 01:40  EA5DOM  0.475608  -27  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-19 01:30  EA5DOM  0.475608  -29  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-19 01:20  EA5DOM  0.475608  -26  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-19 00:50  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-19 00:30  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-19 00:00  EA5DOM  0.475608  -30  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-18 23:30  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-18 23:10  EA5DOM  0.475608  -20  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-18 22:50  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-18 22:30  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-18 22:20  EA5DOM  0.475608  -30  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-18 22:10  EA5DOM  0.475608  -27  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-18 22:00  EA5DOM  0.475608  -23  0  IM98xn  1  FR5DH  LG78pw  8783  129  2018-05-18 21:10  EA5DOM  0.475608  -28  0  IM98xn  1  FR5DH  LG78pw  8783  129 

73, Pascal

73,
Pascal (FR5DH)