Re: LF: EbNaut at 8270.01953125

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

To properly measure that frequency would indeed take 3.17 years, and require a frequency standard comparable those  NPL, NIST etc. have.  ie appreciably better than 1 part in 10^12

I suspect that is just a quoted theoretical frequency

The best we as radio amateurs can usually do is to use GPS which over the long term, ie hours or days, can be considered "spot on" which really means a few parts in 10^12 - probably on a good day, perhaps.

Over the short term,  seconds, tens of seconds, minutes  I wouldn't expect a GPS derived standard to offer much better than a part in 10^10 so only allowing that frequency to be measured as  8270.019531

Andy  G4JNT

On 9 January 2018 at 16:09, David Weinreich <David.Weinreich@globalstar.com> wrote:

Gentlemen,

 

Please excuse a question from one who watches from the sidelines, the amazing reports of contacts at 8.2 kHz.

 

My question is how long does it take to measure 8270.01953125 Hz? Based on my experience, it seems that it would take more than 3 years. Where am I going wrong.

 

Thanks and keep up the good work!!

 

73,

David Weinreich

WA2VUJ/8

 

 

	David Weinreich | Director, Spectrum & Regulatory Engineer 20146 Beach Cliff Blvd. | Rocky River, OH 44116 (OFFICE) 1-216-767-5091 (EMAIL) David.Weinreich@globalstar.com

 

 

From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of DK7FC
Sent: Tuesday, January 09, 2018 10:47 AM
To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: EbNaut at 8270.01953125

 

Hello Riccardo,

My tree is back and i could try to receive you tonite for the first time.
Will you repeat the message again tonite? I would need to switcb to my NS-loop...

73, Stefan


Am 08.01.2018 22:33, schrieb Riccardo Zoli:

 

Hi Paul, VLF

 

Thanks, Paul. Now the noise is a little bit higher. Anyway, the 4th repeat is started at 18:30 UTC (antenna current: about 600mA, windy WX here).

 

All the best

 

73 de Riccardo IW4DXW

 

 

 

 

 

Il 07/Gen/2018 21:20, "Paul Nicholson" <vlf0403@abelian.org> ha scritto:

Riccardo IW4DXW wrote:

> QRG: 8270.01953125
> 3 chars
> 60 sec/sym.
> coding 16K21A
> CRC 8
> duration: 12h 16'

>  start time 18:30 UTC

Sorry, a bit late with today's report.

Todmorden (1412.5 km)
---------------------

 05/06 Eb/N0  +9.4 dB, S/N -24.7 dB/1Hz, phase -141.8 *Decoded*

 06/07 Eb/N0 +10.7 dB, S/N -23.4 dB/1Hz, phase   99.3 *Decoded*

 Previous S/N:
 17/18 -31.5 dB/1Hz;
 18/19 -29.5 dB/1Hz;
 19/20 -27.9 dB/1Hz;
 20/21 -30.9 dB/1Hz;

 Average improvement +5.9 dB;

Bielefeld (845.3 km)
--------------------

 05/06 Eb/N0 -3.7 dB, S/N -37.8 dB/1Hz, phase  -30.8;

 06/07 Eb/N0 +3.5 dB, S/N -30.1 dB/1Hz, phase -163.3 *Decoded*

Cumiana (370.5 km)
------------------

 05/06 Eb/N0 -7.7 dB, S/N -41.8 dB/1Hz, phase 102.4;

 06/07 Eb/N0 +1.2 dB, S/N -32.9 dB/1Hz, phase -54.9 *Decoded*

Warsaw (1035.0 km)
------------------

 05/06 Eb/N0  -4.9 dB, S/N -39.0 dB/1Hz, phase -62.3;

 06/07 Eb/N0 -15.6 dB, S/N -49.7 dB/1Hz;

--
Paul Nicholson
--