Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mb01.r1000.mx.aol.com (Internet Inbound) with ESMTP id 99C023800009C; Thu, 3 Nov 2011 07:28:41 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1RLvSc-0000ne-J3 for rs_out_1@blacksheep.org; Thu, 03 Nov 2011 11:27:54 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1RLvSb-0000nV-UI for rsgb_lf_group@blacksheep.org; Thu, 03 Nov 2011 11:27:53 +0000 Received: from nm25-vm7.bullet.mail.ukl.yahoo.com ([217.146.177.151]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1RLvSb-0000gm-Qk for rsgb_lf_group@blacksheep.org; Thu, 03 Nov 2011 11:27:53 +0000 Received: from [217.146.183.183] by nm25.bullet.mail.ukl.yahoo.com with NNFMP; 03 Nov 2011 11:27:48 -0000 Received: from [217.146.183.162] by tm14.bullet.mail.ukl.yahoo.com with NNFMP; 03 Nov 2011 11:27:48 -0000 Received: from [127.0.0.1] by omp1003.mail.ukl.yahoo.com with NNFMP; 03 Nov 2011 11:27:48 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 455.54773.bm@omp1003.mail.ukl.yahoo.com Received: (qmail 38215 invoked by uid 60001); 3 Nov 2011 11:27:47 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.co.uk; s=s1024; t=1320319667; bh=bEM5HHHgGoC5BnIwyyLRHLPDdeddp5C7WXDPaYfWmuI=; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=ZW/8x2OdJS7ui+6PJpVHFcdIpCXsIAj900HPw+WseMjbfD0r8xYwVl5l9waILRpvUSW8FqLsSn4d9EpZ8G1RPdlG4WLQhe/upkxZxkYfXgRg/lx67Ut6In9PbV5f8SXxLO/Zzt12WKpfTDC4YDiyT5hUIkEUn7qi2h7fhF6nuhY= DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.co.uk; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=l2Vq/KIu0Vcwqo/VaZjRnoPottCUJ3vnzPEPRWlIQ34B1bRDZe14G+u6L/T+BvFpKM9JopXGp3M0pKurUwkp5FGT9InqTfYnEbVEOZuH0WphLEzU1oJT+Jfj/Z1DeRNNpL1po55xwkKt8MxgJMjZFnenS4FS2gFWQ3BFytZ5JMM=; X-YMail-OSG: gm0Z65EVM1mQNZ3NdjPlxKCY3XPHG6bPvh1ktv8yD4xVJZK eL7G33gzO5ooqds5OMwK3B_Ng5mOge8SIKX2.DDLN7FQRtEKGN_efr0EJrnn a7eFTTKPskUO2ritPqc2ssxUkkeOsTJTrgigQX7_FMSvgZ6mGRDkfO9XeXXY s52fP6FbtGyYQuweLIwQ6YumvPBmYVChzNtaKVCn3fbKXRenX1bA1B94AoJi fLc8YZCfSlGX3lxT_DV.q9t2UiPID2dpYAWKilXaysxzeN1OI7IvNHrQ_eVc OHAzOjfLRwe41ebjLd9pQ8xNFJCiIBDU7RH4lZaBqts19wMtCr1GpU3Kj9U6 d1p0lJodDedMjKVwjL.pEFWToBRHs2qpkSEqfB2IpujSSg0v3yCX4DCY4tUb TzPBnHQ-- Received: from [86.139.201.20] by web28103.mail.ukl.yahoo.com via HTTP; Thu, 03 Nov 2011 11:27:46 GMT X-Mailer: YahooMailWebService/0.8.114.317681 References: ,,, <052BA55206094BF087148BC8E0C97027@JimPC> <1320275789.81298.YahooMailNeo@web28104.mail.ukl.yahoo.com> <002301cc99c6$aed71f90$0401a8c0@xphd97xgq27nyf> Message-ID: <1320319666.38048.YahooMailNeo@web28103.mail.ukl.yahoo.com> Date: Thu, 3 Nov 2011 11:27:46 +0000 (GMT) From: M0FMT To: "rsgb_lf_group@blacksheep.org" In-Reply-To: <002301cc99c6$aed71f90$0401a8c0@xphd97xgq27nyf> MIME-Version: 1.0 DomainKey-Status: good (testing) Subject: Re: LF: Re: 8kHz of spectrum Content-Type: multipart/alternative; boundary="474782128-2036485322-1320319666=:38048" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: *** X-Spam-Status: No, hits=3.3 required=5.0 tests=AMATEUR_PORN,HTML_20_30, HTML_MESSAGE,TO_ADDRESS_EQ_REAL 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: 0:2:470224928:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-m009.2 ; domain : yahoo.co.uk DKIM : fail x-aol-sid: 3039ac1d60154eb27ae94e10 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none --474782128-2036485322-1320319666=:38048 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable =0A=0A=0AHi Mal its not the same. We are talking about a maximum of 3kcs se= paration but more likely to be only one to half a kcs. The IF selectivity c= an sort that OK but what it can't do is stop front end being flattened by t= he proximity of a station running hi power. On every other band HF of 600m = we=A0can achieve relatively wide separation. In other words if a station is= desensing my RX on 160 I can go and move and look for a QSOs in the worst = case about 850kcs away=A0or if its CW I would just have to give up like 600= m. But even=A0then on 160 its not too bad largely because of antenna select= ivity which you don't get on 600m owing to the narrowness of the band. Its = not so much the power alone its proximity and power and the=A0narrowness of= the frequency separation.=0AMy guess is you don't have any competition on = 600m because I have never heard a station=A0on the band within your QRA squ= are so maybe you don't understand the phenomenon.=0A=A0=0AAnyway I am worki= ng on it over a period of time but at the moment 600m is a dead-loss around= here because I flatten ADSL in a big=A0way=A0even with mico power. The eff= ect is not temporary because the exchange DSLAM sees 500kcs as noise and sh= uts the data rate down to a level that seems to require human intervention = at the exchange to reinstate the miserly=A01.2mbs that BT laughingly call B= roadband.=0A=A0=0AAny way thanks for the prompt I'll try some more ..... ju= st thought, if you look at the PSK31 screen dumps I attached in another mai= ling yesterday you will see the effect just 50Watts RF out probably between= 1/4 to 1/2 W radiated does to my RX sensitivity from 6 miles away over fai= rly flat terrain.=0AI think it would mess your RX up as well.=0A=0A=A0=0A73= es GL Pete M0FMT IO91UX47VN=0A=0AFrom: mal hamilton =0ATo: rsgb_lf_group@blacksheep.org=0ASent: Thursday, 3 November 2011, 1:1= 9=0ASubject: Re: LF: Re: 8kHz of spectrum=0A=0A=0APete=0AWe all manage on 1= 60 metres where the same criteria applies. You just need selectivity and ex= pertise.=0ASome operators get nervous when Watts are mentioned and prefer u= Watts.=0AYou must be having a hard time with the Mega Watt commercial stati= ons adjacent to the amateur bands, how do you cope ?=0Amal/g3kev=0A=0A-----= Original Message ----- =0A>From: M0FMT =0A>To: rsgb_lf_group@blacksheep.or= g =0A>Sent: Wednesday, November 02, 2011 11:16 PM=0A>Subject: Re: LF: Re: 8= kHz of spectrum=0A>=0A>=0A>Hi all=0A>=0A>In my humble opinion high power on= ly goes with wide band width because ground wave on these medium frequencie= s travels. So I welcome the lower power suggestion (assuming anybody sticks= to it) with the narrow band width proposal. And don't jump on me about fro= nt end selectivity=A0 because I think it is insurmountable even by "Real" A= mateurs.=0A>=0A>73 es GL Pete M0FMT IO91UX47VN=0A>=0A>From: James Moritz =0A>To: rsgb_lf_group@blacksheep.org=0A>Sent: W= ednesday, 2 November 2011, 22:58=0A>Subject: LF: Re: 8kHz of spectrum=0A>= =0A>Dear LF Group,=0A>=0A>Well, I think this is a positive development - th= e only minor disappointment is the reduction in maximum ERP to about 3W.=0A= >=0A>As for the choice of frequency, the maritime people have a plan for a = sort of=A0 "super Navtex" using OFDM modulation with a bandwidth of 10kHz c= entred on 500kHz. It may be that this is just a pipe dream, and/or a way to= justify continued primary user status at 500kHz. But if it ever does come = into existence, it will certainly be using vastly higher powers than amateu= r stations, and the noise sidebands will extend well beyond the actual sign= al bandwidth due to "spectral re-growth" in the TX PA. So it will be good t= o have a significant difference in frequency between ourselves and the nois= y things. I expect all those REAL amateurs will manage to reduce their TX f= requency by 5 percent somehow ;-)=0A>=0A>Cheers, Jim Moritz=0A>73 de M0BMU --474782128-2036485322-1320319666=:38048 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable

 
Hi Mal its not the same. We are talking about a = maximum of 3kcs separation but more likely to be only one to half a kcs. Th= e IF selectivity can sort that OK but what it can't do is stop front end be= ing flattened by the proximity of a station running hi power. On every othe= r band HF of 600m we can achieve relatively wide separation. In other = words if a station is desensing my RX on 160 I can go and move and look for= a QSOs in the worst case about 850kcs away or if its CW I would just = have to give up like 600m. But even then on 160 its not too bad largel= y because of antenna selectivity which you don't get on 600m owing to the n= arrowness of the band. Its not so much the power alone its proximity and po= wer and the narrowness of the frequency separation.
My guess is you don't have any competition on 60= 0m because I have never heard a station on the band within your QRA sq= uare so maybe you don't understand the phenomenon.
 
Anyway I am working on it over a period of time = but at the moment 600m is a dead-loss around here because I flatten ADSL in a big = ;way even with mico power. The effect is not temporary because the exc= hange DSLAM sees 500kcs as noise and shuts the data rate down to a level th= at seems to require human intervention at the exchange to reinstate the miserly = 1.2mbs that BT laughingly call Broadband.
 
Any way thanks for the prompt I'll try some more= ..... just thought, if you look at the PSK31 screen dumps I attached in an= other mailing yesterday you will see the effect just 50Watts RF out probabl= y between 1/4 to 1/2 W radiated does to my RX sensitivity from 6 miles away= over fairly flat terrain.
I think it would mess y= our RX up as well.

 
73 es GL Pete M0FMT IO91UX47VN
From:= mal hamilton <g3kevmal@talktalk.net>
To: rsgb_lf_group@blacksheep.org
Sent: Thursday, 3 November 2011, 1:= 19
Subject: Re: LF: Re: = 8kHz of spectrum

Pete
We all manage on 160 metres where the same criteria= applies. You just need selectivity and expertise.
Some operators get nervous when Watts are mentioned= and prefer uWatts.
You must be having a hard time with the Mega Watt c= ommercial stations adjacent to the amateur bands, how do you cope ?<= /DIV>
mal/g3kev
 
----- Original Message -----
From: M0FMT
Sent: Wednesday, November 02, 2011 1= 1:16 PM
Subject: Re: LF: Re: 8kHz of spectru= m

Hi all

In my humble opinion high power only goes with wide band= width because ground wave on these medium frequencies travels. So I welcom= e the lower power suggestion (assuming anybody sticks to it) with the narro= w band width proposal. And don't jump on me about front end selectivity&nbs= p; because I think it is insurmountable even by "Real" Amateurs.

73 es GL Pete M0FMT IO91UX47VN
<= BR>From: James Moritz <james.moritz@btopenworld.com>
To: rsgb_lf_g= roup@blacksheep.org
Sent: Wednesday, 2 November 2011, 22:58
Subject: = LF: Re: 8kHz of spectrum

Dear LF Group,

Well, I think this is= a positive development - the only minor disappointment is the reduction in= maximum ERP to about 3W.

As for the choice of frequency, the mariti= me people have a plan for a sort of  "super Navtex" using OFDM modulat= ion with a bandwidth of 10kHz centred on 500kHz. It may be that this is just a pipe dream, and/or a way to justify continued primary user statu= s at 500kHz. But if it ever does come into existence, it will certainly be = using vastly higher powers than amateur stations, and the noise sidebands w= ill extend well beyond the actual signal bandwidth due to "spectral re-grow= th" in the TX PA. So it will be good to have a significant difference in fr= equency between ourselves and the noisy things. I expect all those REAL ama= teurs will manage to reduce their TX frequency by 5 percent somehow ;-)
=
Cheers, Jim Moritz
73 de M0BMU
=

--474782128-2036485322-1320319666=:38048--