Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mb02.r1000.mx.aol.com (Internet Inbound) with ESMTP id 9B10A38000081; Wed, 3 Aug 2011 07:05:19 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1QoZF4-0008TN-Kk for rs_out_1@blacksheep.org; Wed, 03 Aug 2011 12:04:02 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1QoZF3-0008TE-OC for rsgb_lf_group@blacksheep.org; Wed, 03 Aug 2011 12:04:01 +0100 Received: from imr-da05.mx.aol.com ([205.188.105.147]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1QoZF1-0005GN-Dx for rsgb_lf_group@blacksheep.org; Wed, 03 Aug 2011 12:04:01 +0100 Received: from mtaomg-mb01.r1000.mx.aol.com (mtaomg-mb01.r1000.mx.aol.com [172.29.41.72]) by imr-da05.mx.aol.com (8.14.1/8.14.1) with ESMTP id p73B3pHh012482 for ; Wed, 3 Aug 2011 07:03:51 -0400 Received: from core-msa001c.r1000.mail.aol.com (core-msa001.r1000.mail.aol.com [172.29.233.65]) by mtaomg-mb01.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id 65226E000081 for ; Wed, 3 Aug 2011 07:03:50 -0400 (EDT) References: <8CE1F480AFAA39A-BE4-3E91@webmail-d146.sysops.aol.com> <4E386F31.10900@iup.uni-heidelberg.de> To: rsgb_lf_group@blacksheep.org In-Reply-To: <4E386F31.10900@iup.uni-heidelberg.de> X-MB-Message-Source: WebUI MIME-Version: 1.0 From: Markus Vester X-MB-Message-Type: User X-Mailer: AOL Webmail 34007-STANDARD Received: from 194.138.39.59 by webmail-d128.sysops.aol.com (149.174.18.18) with HTTP (WebMailUI); Wed, 03 Aug 2011 07:03:50 -0400 Message-Id: <8CE1FE428977AE4-22B4-1BF2@webmail-d128.sysops.aol.com> X-Originating-IP: [194.138.39.59] Date: Wed, 3 Aug 2011 07:03:50 -0400 (EDT) X-AOL-SCOLL-SCORE: 1:2:421944576:93952408 X-AOL-SCOLL-URL_COUNT: 1 X-Spam-Score: 0.3 (/) X-Spam-Report: autolearn=disabled,FORGED_AOL_TAGS=0.281,HTML_MESSAGE=0.001,UNPARSEABLE_RELAY=0.001 Subject: Re: LF: Fieldstrength and radiated power Content-Type: multipart/alternative; boundary="--------MB_8CE1FE428AF48A4_22B4_4114_webmail-d128.sysops.aol.com" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=FORGED_AOL_TAGS,HTML_20_30, 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 x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 1:2:451258048:93952408 X-AOL-SCOLL-URL_COUNT: 1 x-aol-sid: 3039ac1d60164e392b6f43cb X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. ----------MB_8CE1FE428AF48A4_22B4_4114_webmail-d128.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Hi Stefan, LF, there is no peak-hold function, so your carrier has to be present at the gr= abber capture time. Allowing for a bit of clock uncertainty, you would want= to transmit for say 20 seconds around any five minute multiple. Here's an example for ERP calculation:=20 E =3D 20 uV/m at R =3D 200 km distance would give EMRP =3D 26 + 46 + 4 - 49.5 =3D 26.5 dBm =3D 450 mW Dipole ERP =3D 0.82 W To calculate the distance R to my receiver you could use http://no.nonsense.ee/qthmap/?qth=3DJN59NJ69ES Best regards, Markus (DF6NM) -----Urspr=C3=BCngliche Mitteilung-----=20 Von: Stefan Sch=C3=A4fer An: rsgb_lf_group Verschickt: Di., 2. Aug. 2011, 23:46 Betreff: Re: LF: Fieldstrength and radiated power Thanks Markus,=20 Will try now if it works and see what my level will be ;-) Good for PA adju= stments, at least in times without a skywave component. Anyway... So, do we have to send a longer dash or acidentally transmit to the right t= ime? :-) 73, Stefan/DK7FC Am 02.08.2011 18:26, schrieb Markus Vester:=20 Dear LF, =20 to support estimates of radiated power, I have added a fieldstrength readou= t on my LF grabber=20 =20 http://www.alice-dsl.net/df6nm/grabber/Grabber.htm =20 It simply displays the peak frequency and amplitude within the QRSS subband= at the time of the capture (ie. every five minutes). Due to different cali= bration issues, the readout will be accurate only to within about 3 dB. The= re may also be considerable day-to-day variation, for example from switchin= g between different receive antennas. =20 In the region of groundwave dominance (up to 400 km daytime, 200 km in dark= ness), radiated power in dBm or milliwatts can be roughly estimated based o= n distance R using =20 EMRP[dBm] =3D 20 log E[uV/m] + 20 log R[km] + 0.02 R[km] - 49.5 EMRP[mW] =3D 10^(EMRP[dBm]/10) =20 To convert to halfwave-dipole ERP or EIRP, you would have to apply the usua= l factor of 1.83 or 3. =20 Hope this may be useful... =20 Best 73, Markus (DF6NM) ----------MB_8CE1FE428AF48A4_22B4_4114_webmail-d128.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8"
Hi Stefan, LF,
 
there is no peak-hold function, so your carrier has to be present= at the grabber capture time. Allowing for a bit of clock un= certainty, you would want to transmit for say 20 seconds around any fi= ve minute multiple.
 
Here's an example for ERP calculation:
 E =3D 20 uV/m at R =3D 200 km distance would give
 EMRP =3D 26 + 46 + 4 - 49.5 =3D 26.5 dBm =3D 450 mW
 Dipole ERP =3D 0.82 W
To calculate the distance R to my receiver you could use
 
Best regards,
Markus (DF6NM)


= -----Urspr=C3=BCngliche Mitteilung-----
Von: Stefan Sch=C3=A4fer <Stefan.Schaefer@iup.uni-heidelberg.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Di., 2. Aug. 2011, 23:46
Betreff: Re: LF: Fieldstrength and radiated power

Thanks Markus, =

Will try now if it works and see what my level will be ;-) Good for PA adju= stments, at least in times without a skywave component. Anyway...

So, do we have to send a longer dash or acidentally transmit to the right t= ime? :-)

73, Stefan/DK7FC

Am 02.08.2011 18:26, schrieb Markus Vester:=20
Dear LF,
 
to support estimates of radiated power, I have added a fieldstrength r= eadout on my LF grabber
 
 
It simply displays the peak frequency and amplitude within the QRSS su= bband at the time of the capture (ie. every five minutes). Due to different= calibration issues, the readout will be accurate only to within about 3 dB= . There may also be considerable day-to-day variation, for example from swi= tching between different receive antennas.
 
In the region of groundwave dominance (up to 400 km daytime, 200 km in= darkness), radiated power in dBm or milliwatts can be roughly estimated ba= sed on distance R using
 
 EMRP[dBm] =3D 20 log E[uV/m] + 20 log R[km] + 0.02 R[km] - 49.5<= /div>
 EMRP[mW] =3D 10^(EMRP[dBm]/10)
 
To convert to halfwave-dipole ERP or EIRP, you would have to apply the= usual factor of 1.83 or 3.
 
Hope this may be useful...
 
Best 73,
Markus (DF6NM)


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