Return-Path: Received: from mtain-me07.r1000.mx.aol.com (mtain-me07.r1000.mx.aol.com [172.29.96.143]) by air-di04.mail.aol.com (v129.4) with ESMTP id MAILINDI043-eac44c56ebc67d; Mon, 02 Aug 2010 12:01:10 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-me07.r1000.mx.aol.com (Internet Inbound) with ESMTP id 3FBC2380000E2; Mon, 2 Aug 2010 12:01:08 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1OfxQN-00077D-Sq for rs_out_1@blacksheep.org; Mon, 02 Aug 2010 16:59:35 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1OfxQM-000774-NI for rsgb_lf_group@blacksheep.org; Mon, 02 Aug 2010 16:59:34 +0100 Received: from out1.ip07ir2.opaltelecom.net ([62.24.128.243]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1OfxQL-0007s6-07 for rsgb_lf_group@blacksheep.org; Mon, 02 Aug 2010 16:59:34 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AkcFACKIVkxOk8f3/2dsb2JhbACBRIFQjEWQN3GxGJFdhEZzBItP X-IronPort-AV: E=Sophos;i="4.55,303,1278284400"; d="scan'208,217";a="456036413" Received: from unknown (HELO xphd97xgq27nyf) ([78.147.199.247]) by out1.ip07ir2.opaltelecom.net with SMTP; 02 Aug 2010 16:59:25 +0100 Message-ID: <007401cb325b$aba19fe0$0401a8c0@xphd97xgq27nyf> From: "mal hamilton" To: References: <4C51FA69.1030202@iup.uni-heidelberg.de> <4C529C6B.9070908@iup.uni-heidelberg.de> <4C53EB92.4000806@legal-medicine.de> <4C53F284.7070307@iup.uni-heidelberg.de> <2E9DD091D9BA490C9600B92540A7B616@JimPC> <4C56A58C.8020600@iup.uni-heidelberg.de> <229352.77885.qm@web86703.mail.ird.yahoo.com> Date: Mon, 2 Aug 2010 16:59:21 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: VLF: DK7FC's 6th VLF kite experiment Content-Type: multipart/alternative; boundary="----=_NextPart_000_0071_01CB3264.0D3D7140" 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 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: 3039ac1d608f4c56ebc416ae X-AOL-IP: 193.82.116.20 ------=_NextPart_000_0071_01CB3264.0D3D7140 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Yes Dave. I rememember your expeditions to Scotland and I was usually your first= QSO on such missions. also you and I had the first ever 500 Kcs QSO by radio amateurs on the day= the permits were issued=20 Not hrd you for some time, 73 de mal/g3kev ----- Original Message -----=20 From: Dave Pick=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Monday, August 02, 2010 1:18 PM Subject: Re: VLF: DK7FC's 6th VLF kite experiment Well done Stefan! Nothing seen in Birmingham I'm afraid but, as you say, the noise lev= el seemed quite high. Your report reminded me of my first trips to North Scotland with the= kite antenna on 136kHz. Watch out for static charged rain!.... 73 Dave G3YXM ----------------------------------------------------------------------= -------- From: Stefan Sch=C3=A4fer To: rsgb_lf_group@blacksheep.org; Paul ;= Renato Romero ; Bernd Grupe Sent: Monday, 2 August, 2010 12:01:32 Subject: Re: VLF: DK7FC's 6th VLF kite experiment Dear LF/VLF group, Many thanks to all the people who tried to catch may signal in the= yesterdays test! Thanks for taking the time to watch the QRG on a sun= ny sunday! The RX side is an important factor in such a experiment bec= ause it motivates the TX side when there is no QSO but just a receptio= n. It makes me glad that there is such an interest in those tests. Special thanks to Paul Nicholson who did the effort to re-arrange hi= s antenna and software and the website with a nice overview.=20 Also special thanks to Markus/DF6NM for the telephone support about= the activity on the reflector, the lightning situation and the QRN si= tuation. This is an important feedback as well and much more interesti= ng than just having a mobile internet stick. Congratulations to all the successful receiving stations! It was a= test in the middle of the summer time with heavy QRN. The QRN was on= its daily maximum as i was able to transmit at a high kite angle. The= QRN was even high compared to the last days during that time (still= comparable in my DFCW-6000/8,97 window on the grabber1). So, there is= MUCH potential to get a much better S/N in the winther period and at= better wind situations. Thus, i am very hopefully that e.g. Jim and= Paul will catch that signal! This makes the following experiment an= optimistic challenge! I am even sure that it will be possible to go= down in the DFCW-mode, maybe to DFCW-60. This makes it possible to tr= y a cross band QSO (!) like 137kHz/6,47 kHz (or 8,97 first). Here i co= uld use a small portable active antenna for 137 that will not be too= much swayed be the TX antenna... As far as i can see there was a positive reception at least by the= following stations: DF8ZR (QRSS-60 mode, 16km) DK7FC (grabber in DFCW-240 mode, 40km) DD7PC (congrats, first time! 53km) DF6NM (insecure, fragments, 180km) DL4YHF(impressive S/N!, 264km) Best DX reception of the lowest signa= l, transmitted by an amateur so far (far field) Paul Nicholson told me that he has recorded the siganl and will try= to work the trace out. Let's be excited about his proffessional and= nice to read report! Now, i want to give a detailed report of the things that happened on= the TX side: I arrived at about 9:40 UTC. It was no problem to arrange the equipm= ent and nothing was forgotten. Just before, the rain stopped but the= wind was a little to weak. I used the 8,1m^2 kite but it took some hours until the wind was eno= ugh, sadly. First, the wind increased just for some minutes. In that= time i saw that the wire was to long and was sagging to much.=20 After cutting some meters i could start the generator and PA and tur= ned the VFO wheel down until i saw a peak on the amperemeter. It was= on 5,7 kHz but it was due to a very low kite angle. Later, as the win= d increased i could do more useful resonating tests. I found that i ca= n resonate between about 6,4 kHz to 6,6 kHz. Maybe this is due to the= fact that the wire has to be slighty longer than 200m since the kite= braid is elastic and will be 20m (10%) longer at strong wind. After watching the 6,5 kHz sector in the last weeks i found that it= is best to transmit not on n*50 Hz or n*16,6667 Hz (frequency of the= german trains grid). Thus i decided to go about into the center, to= 6470,00 Hz, within the 46 km band! :-) First it was not possible to transmit a real "message" since the win= d was OFF sometimes :-(. My plan was to transmit "CU" in DFCW-600. Than, an accident happened: Suddenly the was was off and i wasn't fa= st enough to bring the kite down on the road. So the 200 =E2=82=AC kit= e dropped in a 15m high tree! I felt like a child that lost his parent= s on the airport! I was not strong enough to pull it out there with it= s braid. I saw no other way to try it with the car, even when the kite= gets damaged with this attempt. So i fastened the braid on the car an= d drove some 10m until there was a heavy pull on it. The braid stopped= in a beginning corner of a corn field and as i lifted it above the co= rn it sounded like a lash/whip. But suddenly the kite came out of the= tree and before it dropped on the bottom it was caught by the wind an= d rised into the sky, hanging on my car :-) I drove back the the TX co= il with the kite on the car... After taking too much sun and after this stress i was powerless and= not motivated to improve the earth losses and so on but it was my abs= olute goal to produce some nice signals for the RX stations, at least= a limple carrier! So i set up the whole arrangement and now the wind= was stable, lifting the kite continously above 45 deg, sometimes 70= deg. In proper wind conditions, it is lifted to 70...80 deg. The antenna current was about 750mA and after connecting the copper= rod i hammered into the soil in the 5th experiment it rised to 800mA.= Then i reduced the primary winding number from 70 to 60. Then, the cu= rrent was up to 920 mA, the highest current so far. Just before 16 UTC= the fuel of the generator was empty and my fuel as well ;-) That was= the end of the 6th experiment. So, my overall losses are about 600 Ohm now. The ERP was about 11mW= and the voltage just about 20 kV rms. I am sure to be able to decreas= e the earth losses to 200 Ohm and the coil losses will be reduced to= 200 Ohm as well since i can reduce the L to come back to 8,97 kHz. Now i know the C of the wire and can make a reasonable tap on the co= il, at arround 275 mH! So, in the 7th experiment i can transmit on 6,4= 7 kHz as well as on 8,97 kHz. I just have to change the coil connectio= n and the VFO frequency and that can be done in < 2 minutes. I will spend some experiments on this 200m antenna now before going= to 300m. And i want to test it on 137 kHz ;-) With a 300m antenna, i= will explore the 58km band in future tests! Also, just for fun, i wa= nt to transmit on 7355 Hz. This frequency is a message in it selfe for= amateurs ;-) So, all in all it was a hard experiment with many difficulties and= the QRN situation could have been at least 15 dB better but it was an= important test to find the tap for the L to come back on the Dreamers= Band (33km) with a 200m vertical. Also we have done some new record= receptions and can be very hopefully that this can be much improved= in the next test, if there is proper wind and less QRN that can be as= sumed when going to the autumn :-) Again thanks to all the group and hope cuagn in the next test! :-) Best 73, Stefan/DK7FC PS: Some photos and screenshots will be displayed on my QRZ.com page= in some days. PPS: Hopefully there will come up further stations on the dreamers= band within this year :-) ------=_NextPart_000_0071_01CB3264.0D3D7140 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
Yes Dave.
I rememember your expeditions to Scot= land and I was=20 usually your first QSO on such missions.
also
you and I had the first ever 500 Kcs= QSO by radio=20 amateurs on the day the permits were issued
Not hrd you for some time,
73 de mal/g3kev
 
----- Original Message -----
From:=20 Dave=20 Pick
Sent: Monday, August 02, 2010= 1:18=20 PM
Subject: Re: VLF: DK7FC's 6th= VLF kite=20 experiment

Well done Stefan!
 
Nothing seen in Birmingham I'm afraid but, as you say, the nois= e=20 level seemed quite high.
Your report reminded me of my first trips to North Scotland wit= h the kite=20 antenna on 136kHz.
Watch out for static charged rain!....

73
Dave G3YXM

From: Stefan Sch=C3= =A4fer <schae= fer@iup.uni-heidelberg.de>
To: rsgb_lf_group@blacksheep.org;=20 Paul <paul@abelian.netcom.co.uk>; Renato Romero <contact@vl= f.it>;=20 Bernd Grupe <bernd.grupe@t-online.de>
Sent: Monday, 2 August, 2010=20 12:01:32
Subject:= Re: VLF:=20 DK7FC's 6th VLF kite experiment

Dear LF/VLF group,
=
Many=20 thanks to all the people who tried to catch may signal in the yester= days test!=20 Thanks for taking the time to watch the QRG on a sunny sunday! The= RX side is=20 an important factor in such a experiment because it motivates the TX= side when=20 there is no QSO but just a reception. It makes me glad that there is= such an=20 interest in those tests.
Special thanks to Paul Nicholson who did= the=20 effort to re-arrange his antenna and software and the website with= a nice=20 overview.
Also special thanks to Markus/DF6NM for the telephone= support=20 about the activity on the reflector, the lightning situation and the= QRN=20 situation. This is an important feedback as well and much more inter= esting=20 than just having a mobile internet stick.

Congratulations to= all the=20 successful receiving stations! It was a test in the middle of the su= mmer time=20 with heavy QRN. The QRN was on its daily maximum as i was able to tr= ansmit at=20 a high kite angle. The QRN was even high compared to the last days= during that=20 time (still comparable in my DFCW-6000/8,97 window on the grabber1).= So, there=20 is MUCH potential to get a much better S/N in the winther period and= at better=20 wind situations. Thus, i am very hopefully that e.g. Jim and Paul wi= ll catch=20 that signal! This makes the following experiment an optimistic chall= enge! I am=20 even sure that it will be possible to go down in the DFCW-mode, mayb= e to=20 DFCW-60. This makes it possible to try a cross band QSO (!) like 137= kHz/6,47=20 kHz (or 8,97 first). Here i could use a small portable active antenn= a for 137=20 that will not be too much swayed be the TX antenna...

As far= as i can=20 see there was a positive reception at least by the following=20 stations:
DF8ZR (QRSS-60 mode, 16km)
DK7FC (grabber in DFCW-24= 0 mode,=20 40km)
DD7PC (congrats, first time! 53km)
DF6NM (insecure, frag= ments,=20 180km)
DL4YHF(impressive S/N!, 264km) Best DX reception of= the=20 lowest signal, transmitted by an amateur so far (far field)

P= aul=20 Nicholson told me that he has recorded the siganl and will try to wo= rk the=20 trace out. Let's be excited about his proffessional and nice to read= =20 report!


Now, i want to give a detailed report of the thin= gs that=20 happened on the TX side:

I arrived at about 9:40 UTC. It was= no problem=20 to arrange the equipment and nothing was forgotten. Just before, the= rain=20 stopped but the wind was a little to weak.
I used the 8,1m^2 kite= but it=20 took some hours until the wind was enough, sadly. First, the wind in= creased=20 just for some minutes. In that time i saw that the wire was to long= and was=20 sagging to much.

After cutting some meters i could start the= generator=20 and PA and turned the VFO wheel down until i saw a peak on the amper= emeter. It=20 was on 5,7 kHz but it was due to a very low kite angle. Later, as th= e wind=20 increased i could do more useful resonating tests. I found that i ca= n resonate=20 between about 6,4 kHz to 6,6 kHz. Maybe this is due to the fact that= the wire=20 has to be slighty longer than 200m since the kite braid is elastic= and will be=20 20m (10%) longer at strong wind.
After watching the 6,5 kHz secto= r in the=20 last weeks i found that it is best to transmit not on n*50 Hz or n*1= 6,6667 Hz=20 (frequency of the german trains grid). Thus i decided to go about in= to the=20 center, to 6470,00 Hz, within the 46 km band! :-)
First it was no= t possible=20 to transmit a real "message" since the wind was OFF sometimes :-(.= My plan was=20 to transmit "CU" in DFCW-600.

Than, an accident happened: Sud= denly the=20 was was off and i wasn't fast enough to bring the kite down on the= road. So=20 the 200 =E2=82=AC kite dropped in a 15m high tree! I felt like a chi= ld that lost his=20 parents on the airport! I was not strong enough to pull it out there= with its=20 braid. I saw no other way to try it with the car, even when the kite= gets=20 damaged with this attempt. So i fastened the braid on the car and dr= ove some=20 10m until there was a heavy pull on it. The braid stopped in a begin= ning=20 corner of a corn field and as i lifted it above the corn it sounded= like a=20 lash/whip. But suddenly the kite came out of the tree and before it= dropped on=20 the bottom it was caught by the wind and rised into the sky, hanging= on my car=20 :-) I drove back the the TX coil with the kite on the car...

= After=20 taking too much sun and after this stress i was powerless and not mo= tivated to=20 improve the earth losses and so on but it was my absolute goal to pr= oduce some=20 nice signals for the RX stations, at least a limple carrier! So i se= t up the=20 whole arrangement and now the wind was stable, lifting the kite cont= inously=20 above 45 deg, sometimes 70 deg. In proper wind conditions, it is lif= ted to=20 70...80 deg.
The antenna current was about 750mA and after connec= ting the=20 copper rod i hammered into the soil in the 5th experiment it rised= to 800mA.=20 Then i reduced the primary winding number from 70 to 60. Then, the= current was=20 up to 920 mA, the highest current so far. Just before 16 UTC the fue= l of the=20 generator was empty and my fuel as well ;-) That was the end of the= 6th=20 experiment.

So, my overall losses are about 600 Ohm now. The= ERP was=20 about 11mW and the voltage just about 20 kV rms. I am sure to be abl= e to=20 decrease the earth losses to 200 Ohm and the coil losses will be red= uced to=20 200 Ohm as well since i can reduce the L to come back to 8,97 kHz.
Now=20 i know the C of the wire and can make a reasonable tap on the coil,= at arround=20 275 mH! So, in the 7th experiment i can transmit on 6,47 kHz as well= as on=20 8,97 kHz. I just have to change the coil connection and the VFO freq= uency and=20 that can be done in < 2 minutes.

I will spend some experim= ents on=20 this 200m antenna now before going to 300m. And i want to test it on= 137 kHz=20 ;-) With a 300m antenna, i will explore the 58km band in future test= s! Also,=20 just for fun,  i want to transmit on 7355 Hz. This frequency is= a message=20 in it selfe for amateurs ;-)

So, all in all it was a hard exp= eriment=20 with many difficulties and the QRN situation could have been at leas= t 15 dB=20 better but it was an important test to find the tap for the L to com= e back on=20 the Dreamers Band (33km) with a 200m vertical. Also we have done som= e new=20 record receptions and can be very hopefully that this can be much im= proved in=20 the next test, if there is proper wind and less QRN that can be assu= med when=20 going to the autumn :-)

Again thanks to all the group and hop= e cuagn in=20 the next test! :-)

Best 73, Stefan/DK7FC

PS: Some phot= os and=20 screenshots will be displayed on my QRZ.com page in some days.
PPS:=20 Hopefully there will come up further stations on the dreamers band= within this=20 year=20 :-)






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