Re: RE: LF: 8270Hz

[uwe-jannsen@kabelmail.de]

Hi Lubos es all,
nice you shifted your grabber.
yesterday at 1618UTC I switched the TX off and now at 1227UTC the carrier is on the air agn.

will Paul Nichelson shift his grabber too?

OK. Peter, some hours later Ill switch to Op.4H.
GL
Uwe/dj8wx

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Von: rsgb_lf_group@blacksheep.org
Gesendet: 04.01.2014 10:11
An: rsgb_lf_group@blacksheep.org
Betreff: RE: LF: 8270Hz

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Hello Uwe!

I saw your signal on 8270Hz yesterday afternoon. Are you transmitting now, please? There is a visible signal on 8269.93 on PA1SDB´s grabber, but it is out of my grabber window (8270 +/- 50mH). Is it your signal or some QRM?

73!

Lubos, OK2BVG

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Date: Fri, 3 Jan 2014 14:30:43 +0100
From: uwe-jannsen@kabelmail.de
To: rsgb_lf_group@blacksheep.org
Subject: LF: 8270Hz

OK.. OK. dreamers, the TX is on the air since 1309UTC.
QRG: 8270.000Hz.
WX: continuous rain but not so strong.
when ever the order comes, I can switch to Op-4H.
GL
Uwe/dj8wx

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Von: rsgb_lf_group@blacksheep.org
Gesendet: 03.01.2014 13:21
An: rsgb_lf_group@blacksheep.org
Kopie: paul@abelian.netcom.co.uk
Betreff: Fw: VLF: 8.275 kHz

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Paul Nicholson put forth the important argument that we'd better stay away from 8280 because it's a multiple of 60 Hz. Mains harmonics tend to drift a bit with the line frequeny so further away is better.

 

Thus I retract my preposition, and suggest instead to stay with the original 8270 Hz.

 

Uwe, go ahead!

 

Best 73,

Markus

 

PS Direct harmonics from 16.67 Hz are relatively weak here, even though the railway is only 400 m away. It looks more like carriers from switchmode power conversion units (eg near 8 kHz), accompanied by the telltale 33 Hz spaced sidebands. Unfortunately these frequencies are not easily predictable.

 

From: Paul

Sent: Friday, January 03, 2014 12:56 PM

To: Markus Vester

Subject: Re: VLF: 8.275 kHz

8970 is well placed with respect to harmonics of
both 50 and 60Hz.

8270/8275 not so good in a 60Hz region.

8124 to 8126 would be a good range, considering
harmonics of 16.67Hz, 50Hz, and 60Hz.

Let me know what is decided, I will switch my spectrogram
over to the new band.

--
Paul Nicholson
--