X-GM-THRID: 1233793876433813848 X-Gmail-Labels: rsgb lf Delivered-To: daveyxm@gmail.com Received: by 10.115.73.3 with SMTP id a3cs215097wal; Sun, 15 Apr 2007 04:45:32 -0700 (PDT) Received: by 10.67.115.11 with SMTP id s11mr1186205ugm.1176637532047; Sun, 15 Apr 2007 04:45:32 -0700 (PDT) Return-Path: Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mx.google.com with ESMTP id 24si7441227ugf.2007.04.15.04.45.28; Sun, 15 Apr 2007 04:45:32 -0700 (PDT) Received-SPF: neutral (google.com: 193.82.116.20 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Hd363-0006P6-2O for rs_out_1@blacksheep.org; Sun, 15 Apr 2007 12:40:43 +0100 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Hd362-0006Ox-7x for rsgb_lf_group@blacksheep.org; Sun, 15 Apr 2007 12:40:42 +0100 Received: from proxy45.bvx.cz ([212.96.165.45]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Hd360-0003MS-PP for rsgb_lf_group@blacksheep.org; Sun, 15 Apr 2007 12:40:42 +0100 Received: from localhost (localhost.localdomain [127.0.0.1]) by proxy45.bvx.cz (Postfix) with ESMTP id 43C5F4E45F0 for ; Sun, 15 Apr 2007 13:42:58 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at smtp.bvx.cz Received: from proxy45.bvx.cz ([127.0.0.1]) by localhost (proxy45.bvx.cz [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id cdy0bnWE4jxc for ; Sun, 15 Apr 2007 13:42:57 +0200 (CEST) Received: from rtv5f9d8dfdf44 (u-220-36.breclav.lan [192.168.220.36]) by proxy45.bvx.cz (Postfix) with ESMTP id 39B6B4E40DA for ; Sun, 15 Apr 2007 13:42:57 +0200 (CEST) From: =?iso-8859-2?Q?Lubom=EDr_Bobal=EDk?= To: Date: Sun, 15 Apr 2007 13:40:11 +0200 Message-ID: <000001c77f52$d3b6d910$0600a8c0@rtv5f9d8dfdf44> MIME-Version: 1.0 X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.2627 Importance: Normal In-Reply-To: <002401c77ef4$cb5f7820$0100a8c0@W1KW> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3028 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: LF: RE: [500 kHz] DI2BO has 1.7 mW ERP! Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C77F63.973FA910" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.3 required=5.0 tests=HTML_50_60, HTML_FONTCOLOR_UNKNOWN,HTML_MESSAGE autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false Status: O X-Status: X-Keywords: X-UID: 6929 This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C77F63.973FA910 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Hello Geri! Thanks for very interesting informations and for your ERP field-measurements. It is really incredible, that I can take snapshot DI2BO in as good quality as I sent you some days before. It is fine, you practice DI2BO with 1.7mW ERP only. DI2AG and BHZ are more stronger (DI2AG especially) and it is useful to have a chance testing RX, ANT and PC receiving signal near the noise. (I have got Praecitronic GF61, MV61, SV61 as well. Good for my LF experiments!) GL and 73! Lubos, OK2BVG ********************************************************************** -----Original Message----- From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Holger 'Geri', DK8KW Sent: Sunday, April 15, 2007 2:27 AM To: rsgb_lf_group@blacksheep.org Subject: LF: [500 kHz] DI2BO has 1.7 mW ERP! Hello Dave and also all the others observing DI2BO (and the other beacons on 500 kHz), Today the weather was fine and I took the chance to drive around and do some ERP field-measurements. Technically I used the MV-62 Measurement Receiver that reads the signal strength in dBu. As an antenna I used a simple open loop with 1 m diameter. To measure the distance to DI2BO I used a Garmin XL-45 handheld GPS system. Mathematically I used a set of formulas that Markus, DF6NM helped me to develop (thanks, Markus!). These formuals come up with the EIRP, the effective radiated power above an isotropic radiator. For those interested in the forumas, please find attached a samle XLS file. For techical details, please ask Markus, he is much of an expert in this than I am ;-) Next I used some ITU definitions to convert EIRP to ERP (DEFINITIONS OF RADIATION IN LF, MF AND HF BROADCASTING BANDS), in which is stated: The value of the e.r.p. is related to the e.i.r.p. by the expression: e.r.p. = 0.61 e.i.r.p. (linear scale) e.r.p. = e.i.r.p. - 2.2 dB (logarithmic scale) Here are the results, measured at three different locations: 1,02 km distnce: 1,63 mW ERP 1,57 km distance: 1,85 mW ERP 2,01 km distance: 1,56 mW ERP The average of these three measurementsis around 1,7 mW ERP! This makes alle your observations even more astonishing. I would not have guessed that a 500 kHz at that ERP level signal would span that distance, espeically audiably. With this low power level it also shows the important efect of QSB from variations in the ionosphere. Until further notice DI2BO will transmit on 505,015 kHz with 1,7 Watt ERP day and night (24/7), so please keep watching and observing and keep thos reports coming in. Best 73 Geri, DK8KW / DI2BO DI2BO: antenna system is a "long wire", simply about 8 m wire vertically up to a 10m mast, then another 8m wite horizontally to the roof of my house. OOutpur power is around 10 Watt (DEBEG 7121 on "reduced power"). ----- Original Message ----- From: "Dave Sergeant" < dave@davesergeant.com> To: < rsgb_lf_group@blacksheep.org> Sent: Saturday, April 14, 2007 7:39 AM Subject: Re: LF: DI2BO > Just to report that when I came back into the shack at 2100z DI2BO > was clearly audible to my ears, peaking 439 here in Bracknell IO91PJ. > I was rather amused to clearly hear it send its CW id 'DI2AG' !! > GI4DPE was also heard beaconing in normal CW around 501.15. > > This maybe highlights the problem with QRSS on 500kHz. I have already > noted slow and very deep QSB on many signals. While I was watching > DI2BO on Argo last night I found that it would pop above my noise > level for only 1 out of 3 or 4 callsign sequences and between that > there was little more than the odd dot visible. When it appeared most > but never all of a complete call was visible and it clearly peaked > quite strong for just a few characters. If I had not known what the > call was I would have had to listen a long time to postively identify > it. However when it sent its ID on normal CW when listening without > Argo later that was copyable in its entirety (admittedly wrong!). > > 73 Dave G3YMC > > > > http://www.davesergeant.com > > ------=_NextPart_000_0001_01C77F63.973FA910 Content-Type: text/html; charset="iso-8859-2" Content-Transfer-Encoding: quoted-printable

Hello Geri!

Thanks for very interesting informations and for your = ERP field-measurements. It is really incredible, that I can take snapshot = DI2BO in as good quality as I sent you some days = before.

It is fine, you practice DI2BO with 1.7mW ERP only. = DI2AG and BHZ are more stronger (DI2AG especially) and it is useful to have a = chance testing RX, ANT and PC receiving signal near the = noise.

(I have got Praecitronic GF61, MV61, SV61 as well. = Good for my LF experiments!)

GL and 73!

 

Lubos, OK2BVG

 

******************************************************= **************** =A0=A0

 

 

-----Original = Message-----
From: owner-rsgb_lf_group@blacksheep.org = [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Holger 'Geri', = DK8KW
Sent: Sunday, April 15, = 2007 2:27 AM
To: = rsgb_lf_group@blacksheep.org
Subject: LF: [500 kHz] = DI2BO has 1.7 mW ERP!

 

Hello Dave and also all the = others observing DI2BO (and the other beacons on 500 = kHz),

 

 

Today the weather was fine = and I took the chance to drive around and do some ERP field-measurements. =

 

Technically I used the = MV-62 Measurement Receiver that reads the signal strength in dBu. As an = antenna I used a simple open loop with 1 m diameter. To measure the distance to = DI2BO I used a Garmin XL-45 handheld = GPS system.

 

Mathematically I used a set = of formulas that Markus, DF6NM helped me to develop (thanks, Markus!). These formuals come up with the EIRP, the effective radiated power above an isotropic radiator. For those interested in the forumas, please find attached a samle XLS file. For techical details, = please ask Markus, he is much of an expert in this than I am = ;-)

 

Next I used some ITU = definitions to convert EIRP to ERP (DEFINITIONS OF RADIATION IN LF, MF AND HF = BROADCASTING BANDS),  in which is stated:  =

 

 

The value of the e.r.p. is = related to the e.i.r.p. by the expression:

e.r.p. =3D 0.61 e.i.r.p. (linear = scale)

e.r.p. =3D e.i.r.p. – 2.2 dB = (logarithmic scale)

 

Here are the results, measured at three = different locations:

1,02 km distnce: 1,63 mW ERP
1,57 km distance: 1,85 mW ERP   
2,01 km distance: 1,56 mW ERP

The average of these three measurementsis around 1,7 mW = ERP!

This makes alle your observations even more astonishing. I would not have guessed that a 500 kHz at that ERP level = signal would span that distance, espeically audiably. With this low power = level it also shows the important efect of QSB from variations in the = ionosphere.

Until further notice DI2BO will transmit on = 505,015 kHz with 1,7 Watt ERP day and night (24/7), so please keep watching and observing and keep thos reports coming in.

Best 73

Geri, DK8KW / DI2BO =

DI2BO: antenna system is a "long = wire", simply about 8 m wire vertically up to a 10m mast, then another 8m wite horizontally to the roof of my house. OOutpur power is around 10 Watt = (DEBEG 7121 on "reduced power").

 

 

----- Original Message = -----

From: "Dave = Sergeant" <dave@davesergeant.com= >

Sent: Saturday, April 14, = 2007 7:39 AM

Subject: Re: LF: = DI2BO

 

> Just to report that = when I came back into the shack at 2100z DI2BO
> was clearly audible to my ears, peaking 439 here in Bracknell = IO91PJ.
> I was rather amused to clearly hear it send its CW id 'DI2AG' !! =
> GI4DPE was also heard beaconing in normal CW around 501.15.
>
> This maybe highlights the problem with QRSS on 500kHz. I have = already
> noted slow and very deep QSB on many signals. While I was watching =
> DI2BO on Argo last night I found that it would pop above my noise =
> level for only 1 out of 3 or 4 callsign sequences and between that =
> there was little more than the odd dot visible. When it appeared = most
> but never all of a complete call was visible and it clearly peaked =
> quite strong for just a few characters. If I had not known what the =
> call was I would have had to listen a long time to postively = identify
> it. However when it sent its ID on normal CW when listening without =
> Argo later that was copyable in its entirety (admittedly = wrong!).
>
> 73 Dave G3YMC
>
>
>
> http://www.davesergeant.com<= /span>
>
>

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