Return-Path: Received: from rly-mc03.mx.aol.com (rly-mc03.mail.aol.com [172.21.164.87]) by air-mc04.mail.aol.com (v126.13) with ESMTP id MAILINMC044-d674b27d4f02e6; Tue, 15 Dec 2009 13:27:23 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-mc03.mx.aol.com (v125.7) with ESMTP id MAILRELAYINMC037-d674b27d4f02e6; Tue, 15 Dec 2009 13:26:58 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NKc3T-0008Bs-Sd for rs_out_1@blacksheep.org; Tue, 15 Dec 2009 18:23:27 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NKc3T-0008Bj-CR for rsgb_lf_group@blacksheep.org; Tue, 15 Dec 2009 18:23:27 +0000 Received: from mailout.toya.net.pl ([217.113.224.27] ident=postfix) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NKc4w-0007TA-Jx for rsgb_lf_group@blacksheep.org; Tue, 15 Dec 2009 18:25:00 +0000 Received: from mail.toya.net.pl (localhost.localdomain [127.0.0.1]) by mail.toya.net.pl (Postfix) with ESMTP id 5426E20000594 for ; Tue, 15 Dec 2009 19:25:15 +0100 (CET) Received: from [192.168.1.103] (unknown [10.11.152.246]) (Authenticated sender: unimlyn) by mail.toya.net.pl (Postfix) with ESMTPSA id 2FF4520000591 for ; Tue, 15 Dec 2009 19:25:15 +0100 (CET) Message-ID: <4B27D48A.7080802@toya.net.pl> Date: Tue, 15 Dec 2009 19:25:14 +0100 From: =?UTF-8?B?UGlvdHIgTcWCeW5hcnNraQ==?= User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <38A51B74B884D74083D7950AD0DD85E828AC77@File-Server-HST.hst.e-technik.tu-darmstadt.de> In-Reply-To: <38A51B74B884D74083D7950AD0DD85E828AC77@File-Server-HST.hst.e-technik.tu-darmstadt.de> X-AV-Checked: ClamAV using ClamSMTP X-Karma: unknown: X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: AW: AW: LF: "Gain" between qrss3 and qrss10? Content-Type: multipart/alternative; boundary="------------070100070409000104040305" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.5 required=5.0 tests=HTML_30_40, HTML_FONTCOLOR_UNKNOWN,HTML_MESSAGE,HTML_TITLE_EMPTY 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-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --------------070100070409000104040305 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Stefan Sch=C3=A4fer wrote: > Mni tnx Rik for your answer! > > =20 > > No, you didn=E2=80=99t spoil the fun at all ;-) > > =20 > > I have some remarks/ideas. > > The coil losses increase linear with the power but not more than=20 > linear. So, 10x the power wouldn=E2=80=99t decrease the antenna efficien= cy (if=20 > no arcing occurs, of course). If we assume an antenna, e.g. in 8m=20 > height with many toploads, then the efficiency will be poor but the=20 > capacitance will be high and thus the needed L will be small.=20 > Therefore we get a low voltage even with very high power and due to=20 > the low efficiency we will keep the legal limit. So, if one has no=20 > possibility to increase the antenna height QRO is one choice,=20 > especially when the operator is already in pension and cannot do a qso= =20 > in qrss10000000000000000000000000 any more ;-) > > =20 > Dear Stefan, LF group I did read all the answers within the topic you've started or , being= =20 more precise, how to get the 1 watt of permitted ERP limit using=20 different ideas concerning antennae, TX power, "gain" due to different=20 modulations ( qrss , FEC related, etc...) Of course, in practical=20 terms an appropriate mixture of all the factors mentioned along with=20 propagation paths and its duration , results in an ability of a given=20 station to make a qso As we all have also some fun with that issue, especially looking at=20 the qrss1//endless repetition of zeros// so let us make this fun to= =20 stay a little longer.. There was one conclusion: bad antenna - go for a QRO - i would go=20 for another extreme .. "good" antenna - go for a QRP the lambda for 137 kHz is, say, 2200 meters, its quarter 550 meters so=20 why not making a GP ( ground plane antenna) :) Assuming 3db loss of a GP wrt dipole to get 1 watt erp we must have a=20 tiny 2 Watt transmitter and.. hire a helicopter for an hour or so =20 to rise that 550 meters of wire and stay in a suspension mode while ,=20 at this time , one can make tens of qso using normal CW ( i did not=20 mention about lambda/4 counterpoises ) when reading about kiloWatts of TX power, corona effects already=20 compared to Northern lights i immediately thought about the 'opposite' = :) = =20 73 de Piotr, sq7mpj qth: Lodz/jo91rs/ p.s . Does anyone know the cost of a helicopter rental ? ( i mean,=20 in practice, statistical average or so) --------------070100070409000104040305 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Stefan Sch=C3=A4fer wrote:

= Mni tnx Rik for your answer!

= =C2=A0

No, you didn=E2=80=99t spoil the fun at all ;-)

=C2=A0

= I have some remarks/ideas.

The coil losses increase linear with the power but not more than linear. So, 10x the power wouldn=E2=80=99t decrease the antenna efficiency (if no arcing occurs, of course). If we assume an antenna, e.g. in 8m height with many toploads, then the efficiency will be poor but the capacitance will be high and thus the needed L will be small. Therefore we get a low voltage even with very high power and due to the low efficiency we will keep the legal limit. So, if one has no possibility to increase the antenna height QRO is one choice, especially when the operator is already in pension and cannot do a qso in qrss10000000000000000000000000 any more ;-)

=C2=A0

Dear Stefan, LF group
I=C2=A0 did read=C2=A0 all the answers within the topic you've started=C2= =A0 or , being more precise,=C2=A0 how to get=C2=A0 the 1 watt of permitted=C2=A0= ERP=C2=A0 limit=C2=A0 using different ideas concerning antennae, TX power, "gain" due to different modulations ( qrss , FEC related,=C2=A0=C2=A0 etc...) Of course,= in practical terms an appropriate mixture of all the factors mentioned=C2=A0 along with propagation paths and its duration , results in an ability of=C2=A0 a given station to make a qso
As=C2=A0 we all have=C2=A0 also some fun=C2=A0 with that issue, especially= looking at the qrss1//endless repetition of zeros// =C2=A0=C2=A0=C2=A0 so let us make= this fun=C2=A0 to stay a little longer..
There was=C2=A0 one=C2=A0 conclusion:=C2=A0 bad antenna=C2=A0 - go for a= QRO=C2=A0=C2=A0 - i would go for another extreme .. "good" antenna - go for a QRP
the lambda for 137 kHz is, say, 2200 meters, its quarter=C2=A0 550 meters= so why not making a GP ( ground plane antenna)=C2=A0=C2=A0 :)
Assuming 3db loss of a GP wrt dipole=C2=A0 to get 1 watt erp we must have= a tiny 2 Watt=C2=A0 transmitter=C2=A0 and.. hire a=C2=A0 helicopter=C2=A0 fo= r=C2=A0 an hour or so=C2=A0 to rise that 550 meters of wire and stay in a suspension mode=C2=A0 while= , at this time , one can make tens of=C2=A0 qso using normal=C2=A0 CW=C2=A0= ( i did not mention about=C2=A0 lambda/4 counterpoises )

when reading about kiloWatts of=C2=A0 TX power, corona effects already compared to Northern lights i=C2=A0 immediately thought about the 'opposite'=C2=A0 :)

=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 73 de Piotr, sq7mpj
qth:=C2=A0 Lodz/jo91rs/

p.s .=C2=A0 Does anyone know=C2=A0=C2=A0 the cost of=C2=A0 a helicopter re= ntal ? ( i mean, in practice, statistical average or so)

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