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[195.171.43.25]) by mx.google.com with ESMTP id e1si3730384wiz.21.1969.12.31.16.00.00; Wed, 25 Sep 2013 05:13:56 -0700 (PDT) Received-SPF: neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) client-ip=195.171.43.25; Authentication-Results: mx.google.com; spf=neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) smtp.mail=owner-rsgb_lf_group@blacksheep.org; dkim=pass (test mode) header.i=@btinternet.com Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1VOncJ-0002fB-IY for rs_out_1@blacksheep.org; Wed, 25 Sep 2013 12:50:51 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1VOncI-0002f2-Hg for rsgb_lf_group@blacksheep.org; Wed, 25 Sep 2013 12:50:50 +0100 Received: from smtpout01.bt.lon5.cpcloud.co.uk ([65.20.0.121]) by relay1.thorcom.net with esmtp (Exim 4.77) (envelope-from ) id 1VOncF-0002jG-3M for rsgb_lf_group@blacksheep.org; Wed, 25 Sep 2013 12:50:49 +0100 X-CTCH-RefID: str=0001.0A090203.5242CE14.01F7,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0 X-Junkmail-Premium-Raw: score=38/97,refid=2.7.2:2013.9.25.44515:17:38.343,ip=86.171.166.126,rules=__HAS_MSGID, __SANE_MSGID, MSGID_32HEX_LC, INVALID_MSGID_NO_FQDN, __HAS_FROM, __PHISH_FROM2, __FRAUD_WEBMAIL_FROM, __TO_MALFORMED_2, __TO_NO_NAME, __BOUNCE_CHALLENGE_SUBJ, __BOUNCE_NDR_SUBJ_EXEMPT, __FRAUD_SUBJ_ALLCAPS, __MIME_VERSION, __CT, __CTYPE_MULTIPART_ALT, __CTYPE_HAS_BOUNDARY, __CTYPE_MULTIPART, __HAS_X_PRIORITY, __HAS_MSMAIL_PRI, __HAS_X_MAILER, USER_AGENT_OE, __OUTLOOK_MUA_1, __USER_AGENT_MS_GENERIC, __ANY_URI, URI_ENDS_IN_HTML, __FRAUD_BODY_WEBMAIL, __URI_NO_WWW, __CP_URI_IN_BODY, __STOCK_PHRASE_8, __SUBJ_ALPHA_NEGATE, SUPERLONG_LINE, __HAS_HTML, BODY_SIZE_10000_PLUS, __MIME_HTML, __TAG_EXISTS_HTML, __STYLE_RATWARE_NEG, RDNS_GENERIC_POOLED, __URI_NS, SXL_IP_DYNAMIC[126.166.171.86.fur], RDNS_SUSP_GENERIC, __PHISH_FROM, __OUTLOOK_MUA, RDNS_SUSP, __FRAUD_WEBMAIL, FORGED_MUA_OUTLOOK X-CTCH-Spam: Unknown Received: from gnat (86.171.166.126) by smtpout01.bt.lon5.cpcloud.co.uk (8.6.100.99.10047) (authenticated as alan.melia@btinternet.com) id 52409C4E00115360 for rsgb_lf_group@blacksheep.org; Wed, 25 Sep 2013 12:50:44 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=btinternet.com; s=btcpcloud; t=1380109847; bh=2BTx/E0unydMO3BIHvMGnwxbEUATPFprcFXoA1pdbyo=; h=Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:X-Mailer; b=QdpUMlmj7NYMTurgdhCzKTLlTvhzKWoTaHyGsZCtSkhqCSchbHmvbG/Crcn1D5LO2avHAzQ1J/U4nLCJlaXl9F2vMCTmVrbyrG3WPmDbuecVxrbA9E5WT5xfejddxvytnWLMnfizQeTr6ZOIiPSxs6OqTxR882DKrzIWoa9Skm0= Message-ID: <7899F5895DF041D487F0057532E92440@gnat> From: "Alan Melia" To: References: ,<524213E5.5000509@iup.uni-heidelberg.de> ,<8C15231456D14C7EA62378D07C17171D@gnat> Date: Wed, 25 Sep 2013 11:22:27 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 X-Antivirus: avast! (VPS 130925-0, 25/09/2013), Outbound message X-Antivirus-Status: Clean X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hi Bob that sounds a good set-up. Excuse my "telling Grandma how to suck eggs" (as we call it) in my last, but I have seen many frustrated LF ops after much work and investment in copper, gain little in ERP :-)) It is all a matter of your local conditions. [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 254fb1f92e9e6a3597761e1cd9a3a730 Subject: Re: LF: TA CW? Content-Type: multipart/alternative; boundary="----=_NextPart_000_0006_01CEB9E1.841175C0" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.6 required=5.0 tests=FORGED_MUA_OUTLOOK, 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: 2994 This is a multi-part message in MIME format. ------=_NextPart_000_0006_01CEB9E1.841175C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi Bob that sounds a good set-up. Excuse my "telling Grandma how to suck = eggs" (as we call it) in my last, but I have seen many frustrated LF ops = after much work and investment in copper, gain little in ERP :-)) It is = all a matter of your local conditions.=20 Yes the 150' runs of your dipole will make substantial capacitive top = load (~600pF) but I guess they droop, as in an inverted "V"?? Paralleled = wires help, provided they are spaced more than about 3 feet apart, = current direction is unimporant as they are not radiating. There are = some interesting measurements on a small antenna at = http://g3nyk.ham-radio-op.net/spiraltop.htm. It was a little impractical = because of the windage :-)) but an interesting experiment, that was = stimulated by an article in a Canadian Broadcast Engineering journal. = (I hope all the links work....I have had some troubles with them) Laurie G3AQC found the the more top capacity he could add the lower his = ground loss became and he finished with a meander that gave around = 1500pF I believe......at 6pF per metre you can see what that means in = length. By measurement we found that once the ground loss ceased to = decrease by adding extra rods and wire.....doubling the top capacity = would further half the ground loss. The catch was the top-load needed to = be over "clear ground" not foliage (he had a bank of Rhododendrons in = his garden, and had to avoid going over those, or any roofs) The = commercial stations use umbrella loading (CFH Halifax NS) or enormous = "fans" at NAA Cutler Ma. The classic GBR Rugby "figure of eight" was = filled-in in later years to increase the capacity of the 16kHz antenna. = This effect does seem to lie unappreciated by a lot of ops but many = can't use it because of lossy trees and buildings in the region of their = antenna. Of course as you will be well aware at these power levels insulator = loss, and corona starts to be a major concern. I think Warren has set = fire to several lengths of plastic water pipe used as insulators and = spreaders :-)) =20 Best wishes. I am sure that if you make the West to East crossing on = 73kHz you will be the first to do it in that direction. Alan G3NYK =20 ----- Original Message -----=20 From: Bob Raide=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Wednesday, September 25, 2013 2:01 AM Subject: RE: LF: TA CW? Alan; I appreciate your input on 73. It was my idea to have Warren Zeigler = file an app just to see what might happen at our FCC. I had heard the = staff at our FCC was instructed to welcome experimenters for the lower = freqs. Warren filed it but told me nothing may come of it but they = granted us the license! I am using a tube amp [3cx3000A7] with pi-net output and can make 2 kw = easily. But only have a 90' high tower and at the top is the center = feed point of my 75 meter double extended zepp. I simply short the open = wire line which runs almost vertically and fed it with allot of = inductance in series! I assume the two 150' legs acts as top loading. = Ground system is from my broadcast experience where for field intensity = surveys 36" wide chicken wire was used with a 100' tower most often and = a 250 transmitter. Eight 50' chicken wire radials produced decent field = on the midband channels [1000 kHz or so] to measure from. Here I am = using several 150' radials of chicken wire radials. I hope to stretch = some out to 300' but that's going to be about it at my location. I have = made it out to Kansas just two days ago with solid QRSS 60 sigs daytime. = =20 I am running just about 1.5 KW into the ant. The voltage at the = feedpoint draws over a 2" spark to a screw driver so am about at the = power top end I think. Here in the finger lakes region of NY State the winter ground = conductivity goes to 8 or better to the NE with several finger lakes = East of me. If I were on the coast I think it would be a snap to hit = the UK over the salt water. Going to be harder for me inland here. Any comments would be appreciated-Bob -------------------------------------------------------------------------= ----- From: alan.melia@btinternet.com To: rsgb_lf_group@blacksheep.org Date: Wed, 25 Sep 2013 01:16:12 +0100 Subject: Re: LF: TA CW? Hi Bob, the propagation conditions are very similar to the other LF = bands ....there is skywave but the ground wave is stronger further. The = usual problem is antenna efficiency .....in rounded figures 73 is 4 = times more difficult than 136, which is 10 times more difficult than = 470/500.=20 Beware of using HF or commercial "folklaw" on ground systems You MUST = measure as you go otherwise you will waste a lot of time and dollars to = no great effect. I measured Ground Loss in experiments with Finbar early = in the 137 era (using a simple transformer-ratio-arm-bridge), and = rolling out "radials" can be a big mistake.....it all depends on your = environment. the first one or maybe two make a difference then it gets = you wont notice the difference To be effective radials on amateur sizes = antennas need to be at least 1/8 wavelength which is over half a mile! = Unlike 160m skin depth in the ground can be 30 feet or more at these = frequencies. A lookat commercial VLF antennas is more helpful. They use = massive capacity top loading, but they can usually choose their site for = its suitability. The only station to make the crossing on 73 when we still had it on = this side was Laurie G3AQC (now SK) He was using 1200W from an ex Decca = Nav TX and a reasonably efficient antenna...... but not that good.His = ERP was probably close to 1watt. Best of Luck ..... its a pity we will not get an allocation there = again. Alan G3NYK (an original UK 73kHz "licence" holder) ----- Original Message -----=20 From: Bob Raide=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Wednesday, September 25, 2013 12:01 AM Subject: RE: LF: TA CW? Stefan; 73 kHz band is going to be difficult from my preliminary tests. = Seems to be a lack of skywave. I think skywave is going to be rather = scarce and best I am doing so far is out to Kansas but it is ground wave = am sure. Got to get the ground system rolled out here soon as lawn = mowing ends. That should help to give me more field strength on all the = bands. Going to try 73 periodically and see what shakes out! I have worked PA0A on CW by ear last winter on 500. Yes our 500 = licenses go down to 470 region. In winter we should have no trouble = working CW by ear am sure and will be looking forward to it as you would = be even further away from me than PA. I also worked into N. Ireland and = I went to SSB and was heard and worked Finbar, EI0CL [I forgot the = suffix of his call] cross mode as he has no SSB authorization. Jay, = Warren and I work regularly Sunday evenings on 510 upper throughout the = Winter months. I see no takers for 73. Gary has a grabber on 73 for us and using = QRSS 500 spec lab and I tried last nite but never saw a trace. With = ground system out this Winter his grabber may be a winner-Bob =20 -------------------------------------------------------------------------= --- Date: Wed, 25 Sep 2013 00:36:21 +0200 From: Stefan.Schaefer@iup.uni-heidelberg.de To: rsgb_lf_group@blacksheep.org Subject: LF: TA CW? Hi Bob,=20 Success! :-) Welcome! :-) Sorry i can't receive on 4000m here since my receivers are mono band = homemade DC converters (for 137 kHz and 472 kHz) and direct sampling = receivers at 0...24 kHz. But, i remember you were the strongest station on MF (is that = 472...479 kHz for your licence?) last season. Are you a CW man as well? = Do you think it is realistic to try for a TA CW QSO? If, then it could = work in november to february. So far i'm only getting sporadic WSPR-2 = decodes at WD2XSH/17. My WSPR signal is QRP though. At least VO1NA = copied my signal in GN37OR last year... Worth a try? I'm continuously doing overnite WSPR-2 tests on 630m. 73, Stefan/DK7FC Am 24.09.2013 23:45, schrieb Bob Raide:=20 All; With Stefan's help I seem to have finally made it into the group. = I am Bob Raide W2ZM with exp. license's for 500, 137, and most recently = 73 kHz band.=20 I am ready to fire up on 72.401 with Qrss 60 if anyone is = interested to try for a capture tonite. Or I can change to 137 if no = one is interested in 4000 meters. 500 kHz call-WE2XGR/6, 137-WE2XEB, 73-WG2XRS/4 Thanks all, Bob ------=_NextPart_000_0006_01CEB9E1.841175C0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi Bob that sounds a good set-up. = Excuse my=20 "telling Grandma how to suck eggs" (as we call it) in my last, but I = have seen=20 many frustrated LF ops after much work and investment in copper, gain = little in=20 ERP :-)) It is all a matter of your local conditions.
 
Yes the 150' runs of your dipole will = make=20 substantial capacitive top load (~600pF) but I guess they droop, as = in an=20 inverted "V"?? Paralleled wires help, provided they are spaced more than = about 3=20 feet apart, current direction is unimporant as they are not radiating. = There are=20 some interesting measurements on a small antenna at http://g3nyk.ham-rad= io-op.net/spiraltop.htm.=20 It was a little impractical because of the windage :-)) but an = interesting=20 experiment, that was stimulated by an article in a Canadian Broadcast=20 Engineering journal.  (I hope all the links work....I have had some = troubles with them)
 
Laurie G3AQC found the the more top = capacity he=20 could add the lower his ground loss became and he finished with a = meander that=20 gave around 1500pF I believe......at 6pF per metre you can see what that = means=20 in length. By measurement we found that once the ground loss ceased to = decrease=20 by adding extra rods and wire.....doubling the top capacity would = further half=20 the ground loss. The catch was = the top-load=20 needed to be over "clear ground" not foliage (he had a bank of = Rhododendrons in=20 his garden, and had to avoid going over those, or any roofs) The = commercial=20 stations use umbrella loading (CFH Halifax NS) or enormous "fans" at NAA = Cutler=20 Ma. The classic GBR Rugby "figure of eight" was filled-in in later years = to=20 increase the capacity of the 16kHz antenna. This effect does seem to lie = unappreciated by a lot of ops but many can't use it because of lossy = trees and=20 buildings in the region of their antenna.
 
Of course as you will be well aware at = these power=20 levels insulator loss, and corona starts to be a major concern. I = think=20 Warren has set fire to several lengths of plastic water pipe used as = insulators=20 and spreaders :-))  
 
Best wishes. I am sure that if you = make the=20 West to East  crossing on 73kHz you will be the first to do it in = that=20 direction.
 
Alan
G3NYK   
----- Original Message -----
From:=20 Bob = Raide=20
Sent: Wednesday, September 25, = 2013 2:01=20 AM
Subject: RE: LF: TA CW?

Alan;
I appreciate your input on 73.  It was my = idea to=20 have Warren Zeigler file an app just to see what might happen at our=20 FCC.  I had heard the staff at our FCC was instructed to welcome=20 experimenters for the lower freqs.  Warren filed it but told = me=20 nothing may come of it but they granted us the license!
I am using = a tube=20 amp [3cx3000A7] with pi-net output and can make 2 kw easily.  But = only=20 have a 90' high tower and at the top is the center feed point of my 75 = meter=20 double extended zepp.  I simply short the open wire line which = runs=20 almost vertically and fed it with allot of inductance in = series! I=20 assume the two 150' legs acts as top loading. Ground system is = from my=20 broadcast experience where for field intensity surveys 36" = wide chicken=20 wire was used with a 100' tower most often and a 250=20 transmitter.  Eight 50' chicken wire radials produced=20 decent field on the midband channels [1000 kHz or so] to measure=20 from.  Here I am using several 150' radials of chicken wire=20 radials.  I hope to stretch some out to 300' but that's going to = be about=20 it at my location.  I have made it out to Kansas just two days = ago with=20 solid QRSS 60 sigs daytime. 
I am running just about 1.5 KW = into the=20 ant.  The voltage at the feedpoint draws over a 2" spark to a = screw=20 driver so am about at the power top end I think.
Here in the finger = lakes=20 region of NY State the winter ground conductivity goes to 8 or better = to the=20 NE with several finger lakes East of me.  If I were on the coast = I think=20 it would be a snap to hit the UK over the salt water.  Going to = be harder=20 for me inland here.
Any comments would be appreciated-Bob
From: alan.melia@btinternet.com
To: = rsgb_lf_group@blacksheep.org
Date:=20 Wed, 25 Sep 2013 01:16:12 +0100
Subject: Re: LF: TA CW?

Hi Bob, the propagation conditions = are very=20 similar to the other LF bands ....there is skywave but the ground wave = is=20 stronger further. The usual problem is antenna efficiency .....in = rounded=20 figures 73 is 4 times more difficult than 136, which is 10 times more=20 difficult than 470/500.
 
Beware of using HF or commercial = "folklaw" on=20 ground systems You MUST measure as you go otherwise you will waste a = lot of=20 time and dollars to no great effect. I measured Ground Loss in = experiments=20 with Finbar early in the 137 era (using a simple=20 transformer-ratio-arm-bridge), and rolling out "radials" can be a big=20 mistake.....it all depends on your environment. the first one or maybe = two=20 make a difference then it gets you wont notice the difference To be = effective=20 radials on amateur sizes antennas need to be at least 1/8=20 wavelength which is over half a mile! Unlike 160m skin depth in = the=20 ground can be 30 feet or more at these frequencies. A lookat = commercial VLF=20 antennas is more helpful. They use massive capacity top loading, but = they can=20 usually choose their site for its suitability.
 
The only station to make the crossing = on 73 when=20 we still had it on this side was Laurie G3AQC (now SK) He was using = 1200W from=20 an ex Decca Nav TX and a reasonably efficient antenna...... but not = that=20 good.His ERP was probably close to 1watt.
 
Best of Luck .....   its a = pity we will=20 not get an allocation there again.
Alan
G3NYK (an original UK 73kHz "licence" = holder)
-----=20 Original Message -----
From:=20 Bob Raide=20
To:=20 rsgb_lf_group@blacksheep.org= =20 Sent:=20 Wednesday, September 25, 2013 12:01 AM Subject:=20 RE: LF: TA CW?

Stefan;
73 kHz band is going to be difficult from = my=20 preliminary tests.  Seems to be a lack of skywave.  I = think=20 skywave is going to be rather scarce and best I am doing so far = is out=20 to Kansas but it is ground wave am sure.  Got to get the ground = system=20 rolled out here soon as lawn mowing ends.  That should = help to=20 give me more field strength on all the bands.  Going to try 73=20 periodically and see what shakes out!
I have worked PA0A on CW by = ear=20 last winter on 500.  Yes our 500 licenses go down to 470 = region. =20 In winter we should have no trouble working CW by ear am sure and = will be=20 looking forward to it as you would be even further away from me than = PA.  I also worked into N. Ireland and I went to SSB and was = heard and=20 worked Finbar, EI0CL [I forgot the suffix of his call] cross mode as = he has=20 no SSB authorization.  Jay, Warren and I work regularly Sunday = evenings=20 on 510 upper throughout the Winter months.
I see no takers = for=20 73.  Gary has a grabber on 73 for us and using QRSS 500 spec = lab and I=20 tried last nite but never saw a trace.  With ground system out = this=20 Winter his grabber may be a winner-Bob
 
Date: Wed, 25 Sep 2013 00:36:21 +0200
From:=20 Stefan.Schaefer@iup.uni-heidelberg.de
To:=20 rsgb_lf_group@blacksheep.org
Subject: LF: TA CW?

Hi Bob,=20

Success! :-) Welcome! :-)

Sorry i can't receive on = 4000m here=20 since my receivers are mono band homemade DC converters (for 137 kHz = and 472=20 kHz) and direct sampling receivers at 0...24 kHz.

But, i = remember you=20 were the strongest station on MF (is that 472...479 kHz for your = licence?)=20 last season. Are you a CW man as well? Do you think it is realistic = to try=20 for a TA CW QSO? If, then it could work in november to february. So = far i'm=20 only getting sporadic WSPR-2 decodes at WD2XSH/17. My WSPR signal is = QRP=20 though. At least VO1NA copied my signal in GN37OR last = year...
Worth a=20 try? I'm continuously doing overnite WSPR-2 tests on = 630m.

73,=20 Stefan/DK7FC


Am 24.09.2013 23:45, schrieb Bob Raide:=20
All;
With Stefan's help I seem to have finally = made it=20 into the group.  I am Bob Raide W2ZM with exp.  = license's for=20 500, 137, and most recently 73 kHz band.
I am ready to fire up = on=20 72.401 with Qrss 60 if anyone is interested to try for a capture=20 tonite.  Or I can change to 137 if no one is interested in = 4000=20 meters.
500 kHz call-WE2XGR/6, 137-WE2XEB, = 73-WG2XRS/4
Thanks all,=20 = Bob
------=_NextPart_000_0006_01CEB9E1.841175C0--