Return-Path: Received: from mtain-mh01.r1000.mx.aol.com (mtain-mh01.r1000.mx.aol.com [172.29.96.213]) by air-da08.mail.aol.com (v129.4) with ESMTP id MAILINDA083-86404cc59072237; Mon, 25 Oct 2010 10:13:07 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mh01.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1D284380005B9; Mon, 25 Oct 2010 10:09:51 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PANiq-0007FA-My for rs_out_1@blacksheep.org; Mon, 25 Oct 2010 15:08:24 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PANip-0007F1-P8 for rsgb_lf_group@blacksheep.org; Mon, 25 Oct 2010 15:08:23 +0100 Received: from cavuit01.kulnet.kuleuven.be ([134.58.240.43]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PANin-0004LX-LO for rsgb_lf_group@blacksheep.org; Mon, 25 Oct 2010 15:08:23 +0100 Received: from smtps02.kuleuven.be (smtpshost02.kulnet.kuleuven.be [134.58.240.75]) by cavuit01.kulnet.kuleuven.be (Postfix) with ESMTP id 76D197B804A for ; Mon, 25 Oct 2010 16:08:06 +0200 (CEST) Received: from ICTS-S-HUB-N4.luna.kuleuven.be (icts-s-hub-n4.luna.kuleuven.be [10.112.9.14]) by smtps02.kuleuven.be (Postfix) with ESMTP id 5FC80F3867 for ; Mon, 25 Oct 2010 16:08:06 +0200 (CEST) Received: from ICTS-S-EXC2-CA.luna.kuleuven.be ([10.112.11.13]) by ICTS-S-HUB-N4.luna.kuleuven.be ([10.112.9.14]) with mapi; Mon, 25 Oct 2010 16:08:06 +0200 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" Date: Mon, 25 Oct 2010 16:08:05 +0200 Thread-Topic: VLF: DK7FC's 8th VLF kite experiment Thread-Index: Act0St26qFxzItoYRAay/7H2oAZplwAAlqiG Message-ID: References: <4CC05B8F.2030406@iup.uni-heidelberg.de> <1237369649.1611432.1287678227104.JavaMail.fmail@mwmweb077> <4CC070EA.30703@iup.uni-heidelberg.de> <4CC1C2EF.8080007@iup.uni-heidelberg.de> ,<4CC588DB.9030004@iup.uni-heidelberg.de> In-Reply-To: <4CC588DB.9030004@iup.uni-heidelberg.de> Accept-Language: nl-NL, nl-BE Content-Language: nl-BE X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: nl-NL, nl-BE MIME-Version: 1.0 X-KULeuven-Information: Katholieke Universiteit Leuven X-KULeuven-Scanned: Found to be clean X-KULeuven-Envelope-From: rik.strobbe@fys.kuleuven.be X-Spam-Score: 0.9 (/) X-Spam-Report: autolearn=disabled,HTML_10_20=0.945,HTML_MESSAGE=0.001 Subject: RE: VLF: DK7FC's 8th VLF kite experiment Content-Type: multipart/alternative; boundary="_000_BF4A524700075746A6467658DFC7102C886E0FF506ICTSSEXC2CAlu_" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=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-sid: 3039ac1d60d54cc58faf5c0b X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) --_000_BF4A524700075746A6467658DFC7102C886E0FF506ICTSSEXC2CAlu_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello Stefan, congrats with the effort and the results. I really must try to participate in the next test (although the distance= between us in meanwhile peanuts). You are giving a new meaning to the saying "the sky is the limit". About the locator JN49IS36VH: if I got it right this is a 12m by 19m recta= ngle, only a small part of the antenna will fit in this rectangle ! 73, Rik ON7YD ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.or= g] namens Stefan Sch=E4fer [schaefer@iup.uni-heidelberg.de] Verzonden: maandag 25 oktober 2010 15:40 Aan: rsgb_lf_group@blacksheep.org CC: Renato Romero; Paul; Bernd Grupe Onderwerp: Re: VLF: DK7FC's 8th VLF kite experiment Dear VLF, So, now after another very successful VLF experiment i want to summarise= some informations and achieved results. First i want to thank all those who did and tried to receive my VLF signal= s on up to 3 different VLF bands! Without so many RX stations, increasing= and increasing numbers, it would not be worth to do that effort all the= time, especially the 300m kite! Thanks for so many RX reports! There are very interesting and different re= sults from different stations. Here, we can learn a lot of VLF propagation= and suitable RX systems, it seems. Special thanks to Marco/DD7PC who was available on the phone to inform me= and made QSP to the reflektor! Most amazing seems to be the results of the 5170 Hz receptions of SQ5BPF= and OE3GHB, with a very impressive S/N! Please, can we have a detailed RX= antenna description and some wideband (0...24 kHz) screenshots? As far as= i know both of these staions are using E field antennas!! Congratulations to the successful receptions! As far as i know, in my 8th= experiment there have been the following results(new=3D bold; new ODX=3Du= nderlined; (distance/km)): Dreamers Band / 33km / 8970Hz: Daniele Tincany(707), DK7FC(40), M0BMU(657), DD7PC(53), DJ2LF(176), DJ8WX(= 461), DK6NI(165), DL3ZID(462), DL4YHF(264), Michael Oexner(72), EI8JK (131= 0!!!!!!!!!!!!!!!!!!!!!! :-) ), F1AFJ(683), IK1QFK(544), OE3GHB(594), PA3CP= M(367), PA3FNY(360), SQ5BPF(904) 46km / 6470Hz: DD7PC(53), DK7FC(40), IK1QFK(544), M0BMU(657), Micheal Oexner (72), OE3GHB= (594), PA3CPM(367), PA3FNY(360), SQ5BPF(904!!!) 58km / 5170Hz: DD7PC(53), DK7FC(40), OE3GHB(594), PA3FNY(360), SQ5BPF(904!!!) There have been some stations without a successful reception. I think in= most cases this is due to a non optimal RX antenna or to much QRM. But bo= th cases can be optimised. QRM=3D> going out in the field (like i do ;-)= ), insufficient effeciency=3D> optimising the RX antenna. In the case of= W1VD, i assume neither the RX nor the QRM is the problem. Here, i/we have= to find the best time for such a test to USA. And: It is nice that the OD= X is increasing in "small" steps. That makes it very exciting, isn't it?= :-) The new DX record by amateurs on VLF is acquired by Tony/EI8JK, 1310 km.= It is very interesting that he used a E/W orientated "earth antenna" to= receive the signal! He already told me that he found some methods to stro= ngly improve the S/N! Although the color scale of the capture is a little= dark, it is an undoubtly reception. If it could be with even better S/N,= as he means, there should be some chance to reach even more distance! We= will see.. So, here my report and some data of the 8th experiment: I arrived on the hill at 5 UTC. It was almost dark and the temp was below= 0 =B0C. The moon enlighted the field, and the sun started to enlight the= sky. There was no wind at all! As i finished building up the system, the= sun came out, at 6 UTC. Still no wind but it came up slowly. At arround= 8 UTC the kite was up and the wind increased to an optimal level without= breaks. So i could transmit a long carrier (1 hour), GPS locked, at 8969.= 975 Hz. After that i had the idea to transmit a short mesage in DFCW-600:= "GM- good morning" ;-) This was successfully received by 17 RX stations= in 8 countries! The kite was stable in an angle of about 70 deg an the average antenna cur= rent was about 900 mA, peaking 1 A, so 16 kV rms on the wire. Since the= earth lossed seemed to be higher, a TX power of 550 W was necessary this= time. This seems to be the limit of this generator but the coil/wire/PA= will at least handle 2 kW, i assume! There was no noticable temp rise at= the PAs heat sink during this 1 hour transmision! :-) So, the ERP was onc= e again up to 27 mW. Marco/DD7PC kept me informed about the traffic in the reflector, tnx. After that it was possible to make QSY to 6470 Hz just by changing the tra= nsmit frequency (within SpecLab!) and the tap of the coil. It took maybe= 2 minutes to become QRV there on 46 km, as can be seen on the captures.= On 6470 Hz, the coils losses are 100 Ohm higher. The achieved antenna cur= rent was 900 mA. Since the wind was even stronger to that time, the averag= e current was 900 mA as well, 20 kV rms on the wire. Thus the maximum ERP= here was 11 mW. Since the generator was running at full power it took very much fuel in a= short time and i thought this could become a problem since i wanted to tr= y a 300m vertical antenna at 5170 Hz as well. So i decided just to transmi= t a 40 min carrier for long time integrations and a "K", to have a trace= that can be undoubtly identified as my transmission. During that time i= rolled out the 100m kite antenna to switch it in series to the 200m anten= na later (exciting experiment!). The wind increased even more during that= time and so it took some time to become QRV there on the 58 km band. I decided to exchange the kite to the smaller version (3.6m^2). This "smal= l" kite took the whole kite line and the 300m wire until i pulled it down= after the 5170 Hz test. But the angle of the antenna was lower, maybe 60= deg (sometimes 70 deg). First a applied my DDS VFO since the resonance ca= n be easier found with the durning knob instead of a SpecLab slider. But= this frequency seems to cause EMC problems in the VFO although it is driv= en by a battery and the output is fed into the PA by a fiber optic cable!= Not so the PC! SpecLab generates the TX frequency and supports the audio= output. I used a homemade fiber optic link (using the 5V of the USB as th= e power supply) working with a class A LED driver. I found that 5170 Hz is not the resonance frequency of this antenna. Actua= lly it is higher, at arround 5290 Hz! At 5290 Hz i got about 850 mA averag= e antenna current! But i decided to stay at 5170 Hz since i wasn't sure ab= out the QRM situation on other frequencies and most of the RX stations (in= cluding my grabber) are focused on this QRG, i assumed. With the variomete= r adjusting for minimum L i reached an average antenna current of 400 mA= on 5170 Hz, so about 6 dB more ERP could have been possible with a suitab= le QRG or wire or coil! This means, the voltage on the wire was about 7 kV= rms and the ERP just 2 mW (!) Anyway, Gerhard/OE3GHB received the 5170 Hz signal with about 20 dB S/N in= 594 km distance, just about 10 Lambda ;-) !! (and SQ5BPF at 10 dB). We should think/ask about how this can be possible!! I do not think that= it is just due to low QRM and a good antenna but due to the propagation= as well!!??? I will repeat the 5170 Hz tests and will try to make the wire a little lon= ger :-) 5170 Hz is critical for some RX locations since the local mains hu= m is already an issue there. But this is just a new challenge to take, isn= 't it? ;-) Now, since i know that the resonance of the 300m wire is at 5290 Hz, i kno= w where to make a 3rd (and last) tap on the coil to come back to 8970 Hz= with a 300m vertical. This will increase the ERP by another 3...4 dB (red= uced coill losses and a factor 2.25 in radiation resistance). 300m and 5170 Hz is my limit! I will not go lower, sorry ;-) Maybe the los= ses and be reduced and/or the power can be increased but here i will stop,= at least with the kite antenna (not with the earth antenna) :-) So, looking forward to the 9th experiment that will probably be in novembe= r 2010. Will you be receiving? :-) Best 73, Stefan/DK7FC PS: I attach the updated VLF reception list of my experiments. Please let= me know if you are missed or so. --_000_BF4A524700075746A6467658DFC7102C886E0FF506ICTSSEXC2CAlu_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hello Stefan,
 
congrats with the effort and the res= ults.
I really must try to participate in= the next test (although the distance between us in meanwhile peanuts).
You are giving a new meaning to the= saying "the sky is the limit".
About the locator JN49IS36VH: if I= got it right this is a 12m by 19m rectangle, only a small part of the ant= enna will fit in this rectangle !
 
73, Rik  ON7YD
 
Van: owner-rsgb_= lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens Stefan= Sch=E4fer [schaefer@iup.uni-heidelberg.de]
Verzonden: maandag 25 oktober 2010 15:40
Aan: rsgb_lf_group@blacksheep.org
CC: Renato Romero; Paul; Bernd Grupe
Onderwerp: Re: VLF: DK7FC's 8th VLF kite experiment

Dear VLF,

So, now after another very successful VLF experiment i want to summarise= some informations and achieved results.

First i want to thank all those who did and tried to receive my VLF signal= s on up to 3 different VLF bands! Without so many RX stations, increasing= and increasing numbers, it would not be worth to do that effort all the= time, especially the 300m kite!
Thanks for so many RX reports! There are very interesting and different re= sults from different stations. Here, we can learn a lot of VLF propagation= and suitable RX systems, it seems.

Special thanks to Marco/DD7PC who was available on the phone to inform me= and made QSP to the reflektor!

Most amazing seems to be the results of the 5170 Hz receptions of SQ5BPF= and OE3GHB, with a very impressive S/N! Please, can we have a detailed RX= antenna description and some wideband (0...24 kHz) screenshots? As far as= i know both of these staions are using E field antennas!!

Congratulations to the successful receptions!  As far as i know, in= my 8th experiment there have been the following results(new=3D bold; new ODX=3Dunderlined; (distance/km)):

Dreamers Band / 33km / 8970Hz:
Daniele Tincany(707), DK7FC(40), M0BMU(657), DD7PC(53), DJ2LF(176),= DJ8WX(461), DK6NI(165), DL3ZID(462), DL4YHF(264), Michael Oexner(72), EI8= JK (1310!!!!!!!!!!!!!!!!!!!!!! :-) ), F1AFJ(683), IK1QFK(544), OE3= GHB(594), PA3CPM(367), PA3FNY(360), SQ5BPF(904)

46km / 6470Hz:
DD7PC(53), DK7FC(40), IK1QFK(544), M0BMU(657), Micheal Oe= xner (72), OE3GHB(594), PA3CPM(367), PA3FNY(360), SQ5BPF(904!!!)=

58km / 5170Hz:
DD7PC(53), DK7FC(40), OE3GHB(594), PA3FNY(360), SQ5BPF(904!!!)

There have been some stations without a successful reception. I th= ink in most cases this is due to a non optimal RX antenna or to much QRM.= But both cases can be optimised. QRM=3D> going out in the field (like= i do ;-) ), insufficient effeciency=3D> optimising the RX antenna. In the case of W1VD, i assume neither the RX nor the QRM= is the problem. Here, i/we have to find the best time for such a test to= USA. And: It is nice that the ODX is increasing in "small" step= s. That makes it very exciting, isn't it? :-)

The new DX record by amateurs on VLF is acquired by Tony/EI8JK, 1310 km.= It is very interesting that he used a E/W orientated "earth antenna&= quot; to receive the signal! He already told me that he found some methods= to strongly improve the S/N! Although the color scale of the capture is a little dark, it is an undoubtly reception. If= it could be with even better S/N, as he means, there should be some chanc= e to reach even more distance! We will see..

So, here my report and some data of the 8th experiment:
I arrived on the hill at 5 UTC. It was almost dark and the temp was below= 0 =B0C. The moon enlighted the field, and the sun started to enlight the= sky. There was no wind at all! As i finished building up the system, the= sun came out, at 6 UTC. Still no wind but it came up slowly. At arround 8 UTC the kite was up and the wind increase= d to an optimal level without breaks. So i could transmit a long carrier= (1 hour), GPS locked, at 8969.975 Hz. After that i had the idea to transm= it a short mesage in DFCW-600: "GM- good morning" ;-) This was successfully received by 17 RX stations in= 8 countries!
The kite was stable in an angle of about 70 deg an the average antenna= current  was about 900 mA, peaking 1 A, so 16 kV rms on the wire= . Since the earth lossed seemed to be higher, a TX power of 550 W was necessary this time. This seems to be the lim= it of this generator but the coil/wire/PA will at least handle 2 kW, i ass= ume! There was no noticable temp rise at the PAs heat sink during this 1= hour transmision! :-) So, the ERP was once again up to 27 mW.

Marco/DD7PC kept me informed about the traffic in the reflector, tnx.

After that it was possible to make QSY to 6470 Hz just by changing= the transmit frequency (within SpecLab!) and the tap of the coil. It took= maybe 2 minutes to become QRV there on 46 km, as can be seen on the captu= res. On 6470 Hz, the coils losses are 100 Ohm higher. The achieved antenna current was 900 mA. Since the wind= was even stronger to that time, the average current was 900 mA as well, 20 kV rms on the wire. Thus the= maximum ERP here was 11 mW.

Since the generator was running at full power it took very much fuel in a= short time and i thought this could become a problem since i wanted to tr= y a 300m vertical antenna at 5170 Hz as well. So i decided just to transmi= t a 40 min carrier for long time integrations and a  "K", to have a trace that can be undoubtly identifi= ed as my transmission. During that time i rolled out the 100m kite antenna= to switch it in series to the 200m antenna later (exciting experiment!).= The wind increased even more during that time and so it took some time to become QRV there on the 58 km band.

I decided to exchange the kite to the smaller version (3.6m^2). This "= ;small" kite took the whole kite line and the 300m wire until i pulle= d it down after the 5170 Hz test. But the angle of the antenna was lower, maybe 60= deg (sometimes 70 deg). First a applied my DDS VFO since the resonanc= e can be easier found with the durning knob instead of a SpecLab slider.= But this frequency seems to cause EMC problems in the VFO although it is driven by a battery and the output is= fed into the PA by a fiber optic cable! Not so the PC! SpecLab generates= the TX frequency and supports the audio output. I used a homemade fiber optic link (using the 5V of the USB as the power supply) work= ing with a class A LED driver.
I found that 5170 Hz is not the resonance frequency of this antenna. Actua= lly it is higher, at arround 5290 Hz! At 5290 Hz i got about 850 mA average antenna current! But= i decided to stay at 5170 Hz since i wasn't sure about the QRM situation= on other frequencies and most of the RX stations (including my grabber)= are focused on this QRG, i assumed. With the variometer adjusting for minimum L i reached an average antenna cu= rrent of 400 mA on 5170 Hz, so about 6 dB more ERP could have been pos= sible with a suitable QRG or wire or coil! This means, the voltage on= the wire was about 7 kV rms and the ERP just 2 mW (!)
Anyway, Gerhard/OE3GHB received the 5170 Hz signal with about 20 dB S/N= in 594 km distance, just about 10 Lambda ;-) !! (and SQ5BPF at 10 dB)= .


We should think/ask about how this can be possible!! I do not think that= it is just due to low QRM and a good antenna but due to the propagation= as well!!???
I will repeat the 5170 Hz tests and will try to make the wire a little lon= ger :-) 5170 Hz is critical for some RX locations since the local mains hu= m is already an issue there. But this is just a new challenge to take, isn= 't it? ;-)

Now, since i know that the resonance of the 300m wire is at 5290 Hz, i kno= w where to make a 3rd (and last) tap on the coil to come back to 8970 Hz= with a 300m vertical. This will increase the ERP by another 3...4 dB (red= uced coill losses and a factor 2.25 in radiation resistance).

300m and 5170 Hz is my limit! I will not go lower, sorry ;-) Maybe the los= ses and be reduced and/or the power can be increased but here i will stop,= at least with the kite antenna (not with the earth antenna) :-)

So, looking forward to the 9th experiment that will probably be in novembe= r 2010. Will you be receiving? :-)

Best 73, Stefan/DK7FC

PS: I attach the updated VLF reception list of my experiments. Please let= me know if you are missed or so.



--_000_BF4A524700075746A6467658DFC7102C886E0FF506ICTSSEXC2CAlu_--