Return-Path: Received: from mtain-ma01.r1000.mx.aol.com (mtain-ma01.r1000.mx.aol.com [172.29.96.9]) by air-mc02.mail.aol.com (v128.1) with ESMTP id MAILINMC024-a8d64bba0b2d2fb; Mon, 05 Apr 2010 12:09:17 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-ma01.r1000.mx.aol.com (Internet Inbound) with ESMTP id ABAD6380000E6; Mon, 5 Apr 2010 12:09:14 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NyoqH-0002ED-3M for rs_out_1@blacksheep.org; Mon, 05 Apr 2010 17:08:01 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NyoqG-0002E2-1l for rsgb_lf_group@blacksheep.org; Mon, 05 Apr 2010 17:08:00 +0100 Received: from smtp6.freeserve.com ([193.252.22.191]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NyoqD-0005io-4a for rsgb_lf_group@blacksheep.org; Mon, 05 Apr 2010 17:08:00 +0100 Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3619.me.freeserve.com (SMTP Server) with ESMTP id B7F017000088 for ; Mon, 5 Apr 2010 18:07:50 +0200 (CEST) Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3619.me.freeserve.com (SMTP Server) with ESMTP id AB3897000063 for ; Mon, 5 Apr 2010 18:07:50 +0200 (CEST) Received: from AGB (unknown [91.109.33.32]) by mwinf3619.me.freeserve.com (SMTP Server) with SMTP id A7A9D7000088 for ; Mon, 5 Apr 2010 18:07:47 +0200 (CEST) X-ME-UUID: 20100405160747686.A7A9D7000088@mwinf3619.me.freeserve.com Message-ID: <39BA19FFA29A4EA9818125B93D755D4C@AGB> From: "Graham" To: References: , In-Reply-To: Date: Mon, 5 Apr 2010 17:07:46 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8089.726 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8089.726 X-Antivirus: avast! (VPS 100405-0, 05/04/2010), Outbound message X-Antivirus-Status: Clean X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: RE: RE: RE: RE: W1VLF 9 Khz Antenna update Putting inductance near the top. Content-Type: multipart/alternative; boundary="----=_NextPart_000_005E_01CAD4E2.83BADF40" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.0 required=5.0 tests=HTML_30_40,HTML_FONTCOLOR_BLUE, HTML_MESSAGE,MISSING_OUTLOOK_NAME 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-sid: 3039ac1d60094bba0b2a3cee X-AOL-IP: 193.82.116.20 ------=_NextPart_000_005E_01CAD4E2.83BADF40 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Rik, Yes , I added a coil to the top of the vertical section of my inve= rted, L and that improved performance on 500k as well as 1.8 / 3.8= Mhz , 40 turns on a 4 inch former , still there now ,originally= with 2 x 40ft x 5 ft separated capacity wires , however the win= d snapped one of the capacity wires connected to the coil and chan= ged the top into 80 feet of wire in a 5 ft separated U section and= the gain increased slightly ..so it look's like the top is acting= 'just' as a capacity section , Ae is end fed against earth by vari= ometer and auto transformer for 500 and a conventional atu for hf= , earth is everything that conducts in the back garden ! 73 - G ..=20 From: Rik Strobbe=20 Sent: Monday, April 05, 2010 4:17 PM To: rsgb_lf_group@blacksheep.org=20 Subject: LF: RE: RE: RE: RE: W1VLF 9 Khz Antenna update Putting induct= ance near the top. Paul, if you put the coil at the top of a tower try to keep it as far as pos= sible from metal object as these can lower the Q. About the "working principle": a coil at the top of the vertical section will reduce the "current def= lation" through the vertical section. The result is a higher average= current and thus a larger radiation resistance (or effective height= if you prefer that). The stange thing is that the improvement measured is (much) more than= the theoretical value if the antenna is surrounded by trees, buidings= etc... In my 136kHz antenna setup the theoretical gain was about 1dB, while= 5dB was measured by PA0SE. I did construct a light weight coil that was just "hanging" at the top= of the vertical section, far away from any lossy objects. So I am not= sure what the effect will be if the coil is close to metel or wet woo= d. I guess the only way to find out is to try ... 73, Rik ON7YD - OR7T ----------------------------------------------------------------------= ---------- Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blackshee= p.org] namens Paul A. Cianciolo [paulc@snet.net] Verzonden: maandag 5 april 2010 16:31 Aan: rsgb_lf_group@blacksheep.org Onderwerp: LF: RE: RE: RE: W1VLF 9 Khz Antenna update Putting inductan= ce near the top. Rik=20 Thanks for that reply. Very interesting material. =20 I am going to attempt to put a coil at the top about 1 meter below whe= re the top hat begins. The value will be approx 1/2 of the overall value needed to resonate. The QTH is hardly the best site for LF VLF so perhaps it will help. Later I take pictures of my QTH and put them on the web, someone sugge= sted that a while ago. This would give others the ability to "Critique" the antenna. I still do not really understand the premise by which coil works to= increase gain. PauLC W1VLF -----Original Message----- From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group= @blacksheep.org]On Behalf Of Rik Strobbe Sent: Sunday, April 04, 2010 5:40 PM To: rsgb_lf_group@blacksheep.org Subject: LF: RE: RE: W1VLF 9 Khz Antenna update Putting inductance= near the top. Hello Paul, after I published my experiences several hams tried elevated loading= coils on 137kHz. Significant improvement was observed when the antenna was surrounded= by high obstacles (trees, buildings), when the antenna was "free" the= re was little or no gain. I have no idea what the effect will be on 9kHz, but if you can insta= ll an elevated loading coil it whitout too much effort I would suggest= to try it. In my case most stations noticed a signal increase of about 1 S poi= nt and PA0SE measured the field strength and noticed a difference of= 5dB. 73, Rik ON7YD - OR7T ----------------------------------------------------------------------= -------- Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksh= eep.org] namens Paul A. Cianciolo [paulc@snet.net] Verzonden: zondag 4 april 2010 22:28 Aan: rsgb_lf_group@blacksheep.org Onderwerp: LF: RE: W1VLF 9 Khz Antenna update Putting inductance nea= r the top. Stefan=20 On page 60 and 61 of the Low Frequency Experimenters Handbook Peter= Dodd RSGB there is an example putting a coil near the top of the ant= enna In this case the transmitter is on 137 Khz and a of a portion (1/2)= of the "L" needed to resonate was moved near the top. According to me= asurements by Rik Strobbe ON7YD an increase of 4 to 5 db was measure= d. Do you think it would be worth the effort to put 1/4 of the total "L= " needed near the top I could do that very easily. PaulC W1VLF -----Original Message----- From: Stefan Sch=E4fer [mailto:owner-rsgb_lf_group@blacksheep.org]= On Behalf Of Stefan Sch=E4fer Sent: Sunday, April 04, 2010 12:49 PM To: rsgb_lf_group@blacksheep.org Subject: AW: W1VLF 9 Khz Antenna update Hello Paul,=20 This sounds really improving!! And this will give a much more effi= cient antenna as before. Also the HV problems will be reduced. Note th= at the goal should not be to make the C as high as possible but first= to make the antenna efficiency as high as possible. This is done be= increasing the effective height and reducing all the losses. Thus i= would recommend now a combination out of option 2 and 3. Maybe you co= uld check with G3YNKs R-C bridge, if the losses are increased with opt= ion 3. You could use a braid of some meters to keep a distance to the= trees although the wire is mounted on the trees.=20 But all in all it sounds very promising!=20 Option 1 is not so much improving i would say. The C would slightl= y increase but not the antenna efficiency i mean... What about the option to place the coil on the 40m tower? That wou= ld be the best improvement you can do! Good luck! Do you already know who could be the next receiving ham station?= ;-) 73, Stefan/DK7FC ----------------------------------------------------------------------= ------ Von: owner-rsgb_lf_group@blacksheep.org im Auftrag von Paul A. Cia= nciolo Gesendet: So 04.04.2010 17:18 An: rsgb_lf_group@blacksheep.org Betreff: LF: W1VLF 9 Khz Antenna update Stefan,Group. An update on the W1VLF hopefully to be 9 KHZ antenna. The 55 meter wire sloping at 45 degrees measured 340 pf as you rec= all. The addition of 2 top hat wires has been made, each over 50 meters= long with a slope to the ground. Wire 1 is terminates at 11 meters above the ground and wire 2 term= inates 20 meters above the ground. Antenna only =3D 340 pf Antenna and Wire 1 West =3D 650 pf=20 Antenna and wire 1 West and wire 2 East =3D 900 pf L to resonate at 9 KHZ now =3D 350 mHy. The L is now coming down to a reasonable size!! For the next step there are 3 possibilities: 1) Change the top 30 meters from a single wire, to 3 wires spread= 1 meter apart at the top to gain perhaps 100 more PF? 2) Get my neighbors permission to use his tree as a support for th= e end rope on wire 1. This will increase wire 1 west about 40 meters= and raise the end from 10 meters to 20 meters. 200 PF more? 3) Run 2 more wires Wire 3 Northwest and Wire 4 Northeast each= would be 20 to 30 meters long and terminate at 30 meters high. Thes= e would be over a forest and I am not sure if this is my best option. It may yield more "C" and lot more losses?? Goal is to try to get antenna "C" to 1200 pf or more All ideas welcome. PauLC W1VLF -----Original Message----- From: Stefan Sch=E4fer [mailto:owner-rsgb_lf_group@blacksheep.or= g]On Behalf Of Stefan Sch=E4fer Sent: Sunday, April 04, 2010 7:44 AM To: rsgb_lf_group@blacksheep.org Subject: AW: Activity 3 Mar 2010 Mike, LF,=20 Wow! 5641km is really impressing! Congrats!! Is there such an activity planned for the "west-stations" as wel= l? We could do the same! I've never been slower than DFCW-10 on LF. Would be interesting= :-) 73, Stefan/DK7FC ----------------------------------------------------------------------= ---- Von: owner-rsgb_lf_group@blacksheep.org im Auftrag von Mike Denn= ison Gesendet: So 04.04.2010 12:09 An: rsgb_lf_group@blacksheep.org Betreff: LF: Activity 3 Mar 2010 An excellent day's activity on 137kHz yesterday with 5 countries received, the furthest easterly station received here and a QSO= with a new country. In the morining, OE5ODL and DJ6GT were received. During the UA tests, five stations were logged (see the attached screen grab - Argo set to QRSS30 and centred on 137.778kHz). The picture shows (from the top) UA0AET (5641km from me); RA3YO; RN3AGC; UA4WPF; and EW6GB who was first received as early as 170= 0UTC. After the formal test I exchanged 'O' reports with EW6GB at 1902= km, using QRSS10. Well done to all concerned. Mike, G3XDV =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D ------=_NextPart_000_005E_01CAD4E2.83BADF40 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Rik,
 
Yes , I added  a coil to the&nbs= p; top =20 of the  vertical section of my inverted, L and that improved = ;=20 performance on 500k as well  as 1.8 / 3.8 Mhz , 40  turns on= a 4=20 inch  former , still  there  now ,originally  with=  =20 2  x 40ft  x 5 ft separated capacity wires , however=20  the  wind  snapped one of the  capacity =20 wires connected to the  coil and changed the  top into= 80 =20 feet of wire in a 5 ft separated  U section and the  ga= in=20 increased slightly  ..so  it look's like the  top is ac= ting=20 'just' as a  capacity section , Ae is end fed against earth = by =20 variometer and   auto transformer  for  500 and a= =20 conventional atu  for hf , earth is  everything that = conducts in=20 the  back  garden !
 
73 - G ..

Sent: Monday, April 05, 2010 4:17 PM
Subject: LF: RE: RE: RE: RE: W1VLF 9 Khz Antenna update Pu= tting=20 inductance near the top.

Paul,
 
if you put the coil a= t the top=20 of a tower try to keep it as far as possible from metal object as thes= e can=20 lower the Q.
 
About the "working=20 principle":
a coil at the top of the= vertical section=20 will reduce the "current deflation" through the vertical section.= The=20 result is a higher average current and thus a larger radiation resista= nce (or=20 effective height if you prefer that).
The stange thing is that= the improvement=20 measured is (much) more than the theoretical value if the antenna is= surrounded=20 by trees, buidings etc...
In my 136kHz antenna setup= the theoretical=20 gain was about 1dB, while 5dB was measured by PA0SE.
I did construct a light we= ight coil that=20 was just "hanging" at the top of the vertical section, far away from= any lossy=20 objects. So I am not sure what the effect will be if the coil is close= to metel=20 or wet wood.
I guess the only way to fi= nd out is to try=20 ...
 
73, Rik  ON7YD - OR7T=
 
Van: owner-rsgb_lf_group@blackshee= p.org=20 [owner-rsgb_lf_group@blacksheep.org] namens Paul A. Cianciolo=20 [paulc@snet.net]
Verzonden: maandag 5 april 2010 16:31
Aan:=20 rsgb_lf_group@blacksheep.org
Onderwerp: LF: RE: RE: RE: W1VL= F 9 Khz=20 Antenna update Putting inductance near the top.

R= ik=20
 
T= hanks for that=20 reply. Very interesting material. 
I= am going to=20 attempt to put a coil at the top about 1 meter below where the top hat= =20 begins.
 
T= he value will be=20 approx 1/2 of the overall value needed to resonate.
T= he QTH is hardly=20 the best site for LF VLF so= perhaps it=20 will help.
 
L= ater I take=20 pictures of my QTH and put them on the web, someone suggested that a= while=20 ago.
T= his would give=20 others the ability to "Critique" the antenna.
 
I= still do not=20 really understand the  premise by which coil works to increase=20 gain.
 
PauLC
W1VLF
-----Original Message-----
From:=20 owner-rsgb_lf_group@blacksheep.org=20 [mailto:owner-rsgb_lf_group@blacksheep.org]On Behalf Of Rik= =20 Strobbe
Sent: Sunday, April 04, 2010 5:40 PM
To:= =20 rsgb_lf_group@blacksheep.org
Subject: LF: RE: RE: W1VLF 9= Khz=20 Antenna update Putting inductance near the top.

Hello Pa= ul,
 
after I published my exp= eriences several=20 hams tried elevated loading coils on 137kHz.
Significant improve= ment was=20 observed when the antenna was surrounded by high obstacles (trees,= buildings),=20 when the antenna was "free" there was little or no gain.
I have no idea what the= effect will be=20 on 9kHz, but if you can install an elevated loading coil it whi= tout too=20 much effort I would suggest to try it.
In my case most stations=   noticed a=20 signal increase of about 1 S point and PA0SE measured the field stre= ngth and=20 noticed a difference of 5dB.
 
73, Rik  ON7YD - OR= 7T
 
Van: owner-rsgb_lf_group@blacksh= eep.org=20 [owner-rsgb_lf_group@blacksheep.org] namens Paul A. Cianciolo=20 [paulc@snet.net]
Verzonden: zondag 4 april 2010 22:28
<= B>Aan:=20 rsgb_lf_group@blacksheep.org
Onderwerp: LF: RE: W1VLF 9 Kh= z Antenna=20 update Putting inductance near the top.

Stefan=20
 
On page 60 and=20 61 of the Low Frequency Experimenters Handbook Peter Dodd RSGB  = ;there is=20 an example putting a coil near the top of the antenna<= /DIV>
In this case=20 the transmitter is on 137 Khz and a of a portion (1/2) of the "L" ne= eded to=20 resonate was moved near the top. According to measurements by= Rik Strobbe=20 ON7YD  an increase of 4 to 5 db  was measured.
 
Do you think it=20 would be worth the effort to put 1/4 of the total "L" needed near th= e=20 top
I could do that=20 very easily.
 
PaulC
W1VLF
 
-----Original Message-----
From:= Stefan Sch=E4fer=20 [mailto:owner-rsgb_lf_group@blacksheep.org]On Behalf Of Ste= fan=20 Sch=E4fer
Sent: Sunday, April 04, 2010 12:49 PM
To= :=20 rsgb_lf_group@blacksheep.org
Subject: AW: W1VLF 9 Khz An= tenna=20 update

Hello= Paul,
 
This sounds really impr= oving!! And this=20 will give a much more efficient antenna as before. Also the HV pro= blems will=20 be reduced. Note that the goal should not be to make the C as high= as=20 possible but first to make the antenna efficiency as high as possi= ble. This=20 is done be increasing the effective height and reducing all the lo= sses. Thus=20 i would recommend now a combination out of option 2 and 3. Maybe= you could=20 check with G3YNKs R-C bridge, if the losses are increased with opt= ion 3. You=20 could use a braid of some meters to keep a distance to the trees= although=20 the wire is mounted on the trees.
But all in all it sound= s very=20 promising!
Option 1 is not so much= improving i=20 would say. The C would slightly increase but not the antenna effic= iency i=20 mean...
 
What about the option= to place the coil=20 on the 40m tower? That would be the best improvement you can=20 do!
 
Good luck!
 
Do you already know who= could be the=20 next receiving ham station? ;-)
 
73, Stefan/DK7FC=

Von: owner-rsgb_lf_group@black= sheep.org im=20 Auftrag von Paul A. Cianciolo
Gesendet: So 04.04.2010=20 17:18
An: rsgb_lf_group@blacksheep.org
Betreff: LF:=20 W1VLF 9 Khz Antenna update

Stefan,Group.
 
An update on=20 the W1VLF hopefully to be 9 KHZ antenna.
 
 
The 55 meter=20 wire sloping at 45 degrees measured 340 pf as you=20 recall.
The addition=20 of 2 top hat wires has been made, each over 50 meters long with a= slope to=20 the ground.
 
Wire 1 is=20 terminates at 11 meters above the ground and wire 2 terminates 20= meters=20 above the ground.
 
Antenna only=20 =3D 340 pf
 
Antenna=20 and  Wire 1 West  =3D 650 pf
 
Antenna=20 and  wire 1 West and wire 2  East  =3D 900=20 pf
 
L to resonate=20 at 9 KHZ now =3D 350 mHy.
 
 
The L is now=20 coming down to a reasonable size!!
 
For the=20 next step there are 3 possibilities:
 
1) Change the=20 top 30 meters from a single wire,  to 3 wires spread 1 meter= apart at=20 the top to gain perhaps 100 more PF?
 
 
2) Get my=20 neighbors permission to use his tree as a support for the end rope= on wire=20 1.  This will increase wire 1 west  about 40 meters and= raise the=20 end from 10 meters to 20 meters. 200 PF more?
 
 
3) Run 2 more=20 wires  Wire 3 Northwest and Wire 4 Northeast  each would= be 20 to=20 30 meters long and terminate at 30 meters high.   These= would be=20 over a forest and I am not sure if this is my best=20 option.
It may yield=20 more "C" and lot more losses??
 
Goal is to=20 try to get antenna "C" to 1200 pf or more
 
All ideas=20 welcome.
 
PauLC
W1VLF
 
 
 
-----Original Message-----
From:= Stefan Sch=E4fer=20 [mailto:owner-rsgb_lf_group@blacksheep.org]On Behalf Of S= tefan=20 Sch=E4fer
Sent: Sunday, April 04, 2010 7:44 AM
T= o:=20 rsgb_lf_group@blacksheep.org
Subject: AW: Activity 3= Mar=20 2010

Mike,= LF,
 
Wow! 5641km is really= impressing!=20 Congrats!!
 
Is there such an acti= vity planned for=20 the "west-stations" as well? We could do the same!
 
I've never been slowe= r than DFCW-10=20 on LF. Would be interesting :-)
 
73, Stefan/DK7FC

Von: owner-rsgb_lf_group@bla= cksheep.org im=20 Auftrag von Mike Dennison
Gesendet: So 04.04.2010=20 12:09
An: rsgb_lf_group@blacksheep.org
Betreff:<= /B> LF:=20 Activity 3 Mar 2010

An excellent day's activity on 137kHz yesterda= y with 5=20 countries
received, the furthest easterly station received he= re and a=20 QSO with
a new country.

In the morining, OE5ODL and DJ= 6GT were=20 received.

During the UA tests, five stations were logged= (see the=20 attached
screen grab - Argo set to QRSS30 and centred on=20 137.778kHz).
The picture shows (from the top) UA0AET (5641km= from me);=20 RA3YO;
RN3AGC; UA4WPF; and EW6GB who was first received as ea= rly as=20 1700UTC.

After the formal test I exchanged 'O' reports wi= th EW6GB=20 at 1902km,
using QRSS10.

Well done to all=20 concerned.

Mike,=20 G3XDV
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D



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